Difference between revisions of "S20: Nimble"

Latest revision as of 04:45, 23 May 2020

Nimble Logo

1 Nimble Autonomous RC Car
2 Abstract
- 2.1 Introduction
3 Team Members & Responsibilities
4 Team Deliverables Schedule
5 Parts List & Cost
6 Printed Circuit Board
7 CAN Communication
8 Sensor ECU
9 Motor ECU
10 Geographical Controller
11 Communication Bridge Controller
12 Driver Controller & LCD
13 Mobile Application
- 13.1 Software Design
- 13.2 Technical Challenges
14 Conclusion

Nimble Autonomous RC Car

Abstract

In this project, an autonomous vehicle framework for an RC car is presented using dedicated ECUs for motor control, on-board LCD display, steering control, sensor information handling, and communication bridging. A mobile application was also developed that allows for a user to set a destination, and receive updates on the RC car's position via a Bluetooth connection to the GPS unit. CAN communication between sensors and ECUs was defined via a DBC file. Code was developed using test-driven design principles in order to lower time spent debugging. Unit testing was performed using the CMock framework.

Introduction

The project was divided into these modules:

Sensor node
Motor node
Driver node
GPS node
Bridge control node
LCD node
Mobile application

The objective was to create an autonomous vehicle that could navigate to a given GPS coordinate sent via a mobile application. The vehicle moves towards the target position Using a pre-compiled list of checkpoints, and handles obstacles along the way via its ultrasonic and infrared sensors. Updates on Nimble's position are sent to the mobile application via bluetooth.

Flow chart of RC car module interaction

Team Members & Responsibilities

Tanmay Chandavarkar LinkedIn Gitlab
- Sensor Module
- RC Integration and testing
- Wiki

Yuming Cheng Gitlab
- Motor Module
  - GPS Module
  - Driver Module (Master Module)
  - LCD display
  - RC Integration and testing
- Wiki

Ellis Makwana LinkedIn Gitlab
- Sensor Module
- Wiki

Naeem Mannan Gitlab
- Wiki
- Mobile Application
- Bridge Controller

Francesco Vescio Gitlab
- Wiki
- Code Review

Lawrence Wan LinkedIn Gitlab
- GPS Module
- Driver Module (Master Module)
  - Motor Module
  - LCD display
  - Sensor Module
  - Bridge Module
- RC Integration and testing
- Wiki

Team Deliverables Schedule

WEEK	START DATE	END DATE	TASK DETAILS	STATUS
1	Feb 2020	4 March 2020	Create and establish GitLab repository Establish slack channel and invite Preet Look through previous years projects and study it Distribute major roles among team members	Complete Complete Complete Complete
2	05 March 2020	12 March 2020	Create a Bill of Materials. Select and order an RC car. Make Repo on Gitlab for all modules - Follow Naming Convention. Making the Wiki schedule.	Complete Complete Complete Complete
3	13 March 2020	19 March 2020	Select Part Number for Sensors (Tanmay, Ellis ) Designing and deciding PCB tool(Lawrence ) Finalizing GPS module by doing some research (Yuming ) Finalize and order LCD (Francesco ) Finalize Motor and Order it (Lawrence , Yuming ) Environmental setup of mobile app (Naeem ) 3/17/2020 -> Project Lab - RC Car Infrastructure	Complete Complete Complete Complete Complete Complete Complete
4	20 March 2020	26 March 2020	Understand DBC and implement the DBC file compatible with all the controllers. (Updating the DBC files from all nodes) Finish purchasing the Sensor (Tanmay) Establish communication across all the CAN controllers over CAN bus based on the DBC file. Verify the power-up interactions and configurations between Master and the other controllers. Establish a connection over Bluetooth and mobile app.(Naeem) 3/24/2020 -> Project Lab - GPS & Compass Node 3/24/2020 -> Anonymous Reviews	Complete Complete Complete Complete Complete Complete Complete
5	27 March 2019	09 April 2019	3/24/2020 -> Finish deciding the Pins that will be used in each nodes. 3/30/2020 -> Completed the rough draft of block digram and Flow chart for each node logics. Establish a communication between Bluetooth devices.(Naeem) Interfacing of ultrasonic sensors to the SJTwo board and check for basic functionality. (Tanmay, Ellis) Interface of Servo & DC motor to the SJTwo board and check for basic functionality. (Yuming) Interface Compass module with SJTwo board using I2C serial bus. (Lawrence) Interface GPS module with SJTwo board. (Lawrence) Interface bluetooth module with SJtwo board using serial Communication. (Naeem) Configure bluetooth module name as Nimble using Communication Mode. (Naeem) Add a TextView for displaying the Bluetooth connection status in mobile App.(Naeem) Explore UI designing of LCD. (Lawrence & Yuming &Naeem) 4/01/2020 -> Updated Overall DBC file. 4/01/2020 -> Update the wiki schedule. 4/04/2020 -> Completed the Circuit designs for the PCB. 4/04/2020 -> Finalized the components for PCB.	Complete Complete Complete Complete Complete Complete Complete Complete Complete Complete Complete Complete Complete Complete Complete
6	10 April 2020	16 April 2020	Implement basic obstacle avoidance algorithm based on sensor data and test the same. (Lawrence & Yuming) Continue testing motor driver via commands from CAN bus. Build in speed steps to reverse motor for reverse to work correctly. (Yuming) Mount all the sensors and test for any dead band and modify their positions for maximum coverage.(Lawrence & Yuming) Integrate the Ultrasound sensor to get overall feedback. (Tanmay & Ellis) Develop algorithm to avoid obstacles and plan the car's further navigation path. (Lawrence & Yuming) Complete final prototype of the obstacle avoidance feature. (Lawrence & Yuming) Calibrate Compass Module. Develop code for Compass module communication over CAN. (Lawrence) Test Run the Motors driven by wheel feedback and sensors, Basic obstacle avoidance. (Lawrence & Yuming) 4/16/2020 -> Update the wiki schedule.	Complete Complete Complete Complete Complete Complete Complete Complete Complete Complete
7	17 April 2020	23 April 2020	Configure GPS device baud rate and interface it with SJOne board using UART. (Lawrence) Send and receive current location, destination and checkpoint coordinates to and from App and Geo module via BRIDGE.(Lawrence) Calibrate sensors readings and work on filtering algorithm with Master & Sensor Begin work on LCD to show vehicle status(RPM speed, Sensor data, GPS & compass etc.) (Lawrence & Yuming) Finish implementing speed control on motor (to make sure requested speed is met based on RPM read).(Yuming) Work on Car reversing using Motor Controllers.(Lawrence & Yuming) Integrate all modules with the Master to test the data flow. (Lawrence & Yuming) Validation & Verification of obstacle avoidance, steering logic with rear sensor inputs and reversing. (Lawrence & Yuming) Start incorporating GEO Controller information to Master module Steering logic.(Lawrence) Decide, implement and test data exchange between Geo Controller and BRIDGE.(Lawrence) Calculate and send simple bearing angle and destination status on CAN to figure out initial challenges. (Lawrence) Add a Google Map for setting the car's destination. (Naeem) Send car location to app and check points received to Geo module. (Naeem) DEMO video: 4/21/2020 -> Progress report 1 (Lawrence & Yuming)	Complete Complete Complete Complete Complete Complete Complete Complete Complete Complete Complete Complete Complete Complete
8	24 April 2020	30 April 2020	Testing & Validation of the LCD and display vehicle status. (Lawrence & Yuming) Improve & Validate Navigation logic with multiple checkpoints, bearing angle and destination information. (Lawrence) Identify and mitigate GPS locking, Location Accuracy and Number of Satellite-In-View coming. (Lawrence) Validate Accuracy of Compass Calibration with iPhone Compass. (Lawrence & Yuming) Determine and add DBC Changes and finalized. (Lawrence) Implement the steering logic with bearing angle and status provided by GEO-Module. (Lawrence & Yuming) Send additional vehicle status information from can bus to the App for display. (Naeem) Field test and check for obvious issues in obstacle avoidance, navigation, maintaining speed (up/down hill). (Lawrence & Yuming) Update Wiki with new details and information. DEMO video: 4/28/2020 -> Progress report 2 (Lawrence & Yuming)	Complete Complete Complete Complete Complete Complete Complete Complete Complete Complete
9	1 May 2020	7 May 2020	FIELD TESTING - CRITICAL WEEK Check for Corner cases for steering logic under various conditions and locations. (Lawrence & Yuming) Analyse field test results for GPS and CMPS and work on it if required. (Lawrence) Test the location data from the Geo-controller sensor and Navigation Algorithm. (Lawrence) Check overall robustness of the complete system. (Lawrence & Yuming & Tanmay) Establish complete connection on PCB (Lawrence) Update wiki with details. Midterm: 5/1/2020 -> Online Coding (All Class) DEMO Video: 5/5/2020 -> Project Prototype (Lawrence & Yuming)	Complete Complete Complete Complete Complete Complete Complete Complete Complete
10	8 May 2020	21 May 2020	Working on testing and final bug fixes. (Lawrence & Yuming & Naeem) Check for tuning or calibration of modules if required.(Lawrence & Yuming) Complete end-to-end testing for various scenarios and conditions. (Lawrence & Yuming) Create the semester long project activity video and upload to YouTube. (Lawrence) Individual Evaluation: 5/19/2020 (All Class) Final: 5/19/2020 -> Online Coding (All Class) LIVE DEMO: 5/20/2020 -> Final Project (Lawrence & Yuming)	Complete Complete Complete Complete Complete Complete Complete
11	22 May 2020		SUBMISSION: 5/22/2020 -> Final Project Wiki (Lawrence & Ellis & Yuming & Tanmay & Naeem & Frank)	Complete

Parts List & Cost

Item#	Part Desciption	Vendor	Qty	Cost
1	RC Car	Traxxas - Amazon [1]	1	$168.84
2	CAN Transceivers MCP2551-I/P	Robotshop [2]	6	$ 6.00 per unit including shipping fee
3	GPS & Antenna	Amazon []	1	$ 78.24 including shipping fee
4	Compass	Amazon []	1	$ 41.48 including shipping fee
5	Ultrasonic sensors(LV-MaxSonar-EZ0)	SparkFun [3]	1	$ 29.95
6	Ultrasonic sensors (LV-MaxSonar-EZ1)	SparkFun [4]	2	$ 51.90
7	IR sensors (GP2Y0A21YK)	SparkFun [5]	1	$ 34.23 including shipping fee and tax
8	PCB Fabrication	JLCPCB	5	$ 39.13 including shipping fee and tax
9	IR Optocoupler	Amazon	5	$ 40.01 including one day shipping fee and tax
10	20x4 LCD Display	Adafruit [6]	5	$ 0.00 (Provided by Naeem Mannan)

Printed Circuit Board

Design and Architecture

The PCB made for the Project Nimble RC car was initially designed in EAGLE, however, due to the board size limitations, the PCB had to be designed using DipTrace instead. This design was the first and only iteration in designing the layout of the PCB. The design of the PCB was designed around the four SJTWO LPC4078 micro-controllers required for us to use for the project, the DRIVER, MOTOR, GEOGRAPHICAL, and BRIDGE/SENSOR nodes. The PCB layout consists of four through-hole "slots" where the controllers will be connected (with respect to the controllers' orientation and ports/pins) to the PCB. The power section includes a USB socket as well as a through-hole mount for a LM7805 regulator. Through-hole header pins are also included for the components needed for their respective controllers such as the sensors, LCD, GPS, Compass, etc.. LED circuits were added to provide visual information for the user to indicate the motor and servo motion states, as well as to indicate if a sensor has detected an object. Lastly, the design for the CAN bus includes the connections needed for power, RX/TX, and the CAN low and CAN high bus. The dimensions of the PCB are approximately 4 by 9 inches.

Fabrication

Fabrication of the PCB design was done by JLCPCB located in Hong Kong. The PCB was designed using 2-layers and lead-free coating. The fabrication was done relatively quickly, however, due to the COVID-19 outbreak, delivery of the PCB was delayed.

Challenges

Some challenges encountered when designing the PCB was the delay in pinout information needed to begin designing the PCB. It is advised to order parts early and determine what ports/pins are needed as soon as possible to begin designing and ordering the PCB. Another challenge was some issues with the files needed to be manufactured. Since the design had to be designed using DipTrace instead of EAGLE, exporting the necessary files needed to order for fabrication is slightly different than EAGLE.

CAN Communication

All the controllers on Nimble communicate with each other via CAN(control area network) bus with termination resistors. 120-ohm termination resistors avoid signal reflection. Can is basically a broadcast bus that operates on standard baud rates like 100K, 125K, 250K, 500K, or 1Mbps. It is based on half-duplex communication over a differential pair.

CAN communication is based on the priority of messages in case of bus arbitration. A lower ID message always has a higher priority. Nimble’s DBC is shown in the next section which is used to generate CAN messages

To detect modules that are missing in action due to error in reception, MIA is configured. It replaces the data with safe values when the communication cuts off. Below is an example snippet of code that configures CAN MIA for the driver controller which sets default values for data sent from the sensor, geographical, and motor controller. It also configures a mia threshold which is the amount of time that should pass before an MIA should occur and replace the values for its respective module data structure.

 const uint32_t dbc_mia_threshold_SENSOR_DATA = 10 * 100;
 const uint32_t dbc_mia_threshold_COMPASS = 10 * 100;
 const uint32_t dbc_mia_threshold_MOTOR_DATA = 10 * 100;
 
 const dbc_SENSOR_DATA_s dbc_mia_replacement_SENSOR_DATA = {};
 
 const dbc_COMPASS_s dbc_mia_replacement_COMPASS = {};
 
 const dbc_MOTOR_DATA_s dbc_mia_replacement_MOTOR_DATA = {};

Hardware Design

Overall diagram of CAN

Overall diagram of CAN - With other correspondence devices on Controller

DBC File

Shown below is the DBC implementation for this project.

VERSION ""

NS_ :
	BA_
	BA_DEF_
	BA_DEF_DEF_
	BA_DEF_DEF_REL_
	BA_DEF_REL_
	BA_DEF_SGTYPE_
	BA_REL_
	BA_SGTYPE_
	BO_TX_BU_
	BU_BO_REL_
	BU_EV_REL_
	BU_SG_REL_
	CAT_
	CAT_DEF_
	CM_
	ENVVAR_DATA_
	EV_DATA_
	FILTER
	NS_DESC_
	SGTYPE_
	SGTYPE_VAL_
	SG_MUL_VAL_
	SIGTYPE_VALTYPE_
	SIG_GROUP_
	SIG_TYPE_REF_
	SIG_VALTYPE_
	VAL_
	VAL_TABLE_

BS_:

BU_: DBG DRIVER IO MOTOR SENSOR BRIDGE GPS COMPASS CMP

BO_ 150 MOTOR_CMD: 3 DRIVER
 SG_ MOTOR_CMD_STEERING : 0|8@1+ (1,-2) [-2|2] "" MOTOR 
 SG_ MOTOR_CMD_SPEED : 8|8@1+ (1,-25) [-25|25] "" MOTOR

BO_ 151 MOTOR_DATA: 4 MOTOR
 SG_ MOTOR_DATA_RPM: 0|32@1+ (1,0) [0|0] "" DRIVER

BO_ 200 SENSOR_DATA: 8 BRIDGE
 SG_ SENSOR_SONARS_left : 0|16@1+ (1,0) [0|0] "cms" DRIVER
 SG_ SENSOR_SONARS_mid : 16|16@1+ (1,0) [0|0] "cms" DRIVER
 SG_ SENSOR_SONARS_right : 32|16@1+ (1,0) [0|0] "cms" DRIVER
 SG_ SENSOR_IR_rear : 48|16@1+ (1,0) [0|0] "cms" DRIVER

BO_ 300 GPS_DESTINATION_INFO: 8 BRIDGE
SG_ GPS_DESTINATION_LAT : 0|32@1+ (0.000001,-90.000000) [-90|90] "degrees" DRIVER,GPS,MOTOR
SG_ GPS_DESTINATION_LONG : 32|32@1+ (0.000001,-180.000000) [-180|180] "degrees" DRIVER,GPS,MOTOR

BO_ 301 GPS_CURRENT_INFO: 8 GPS
SG_ GPS_CURRENT_LAT : 0|32@1+ (0.000001,-90.000000) [-90|90] "degrees" DRIVER,BRIDGE,MOTOR
SG_ GPS_CURRENT_LONG : 32|32@1+ (0.000001,-180.000000) [-180|180] "degrees" DRIVER,BRIDGE,MOTOR

BO_ 302 COMPASS: 6 GPS 
 SG_ CMP_DEST_BEARING : 0|16@1+ (0.1,0) [0|359.9] "degrees" DRIVER,BRIDGE,MOTOR
 SG_ CMP_CURRENT_HEADING : 16|16@1+ (0.1,0) [0|359.9] "degrees" DRIVER,BRIDGE,MOTOR
 SG_ CMP_DISTANCE : 32|16@1+ (0.01,0) [0|0] "meters" DRIVER,BRIDGE 
   
BO_ 105 SENSOR_DEBUG: 1 BRIDGE
 SG_ IO_DEBUG_CAN_init : 0|1@1+ (1,0) [0|0] "" DBG
 SG_ IO_DEBUG_sensor_init : 1|1@1+ (1,0) [0|0] "" DBG
 SG_ IO_DEBUG_sensor_data : 2|1@1+ (1,0) [0|0] "" DBG
 SG_ IO_DEBUG_bus_off : 3|1@1+ (1,0) [0|0] "" DBG
 
BO_ 106 MOTOR_DEBUG: 6 MOTOR
 SG_ IO_DEBUG_CAN_init : 0|1@1+ (1,0) [0|0] "" DBG,DRIVER
 SG_ IO_DEBUG_bus_off : 1|1@1+ (1,0) [0|0] "" DBG,DRIVER
 SG_ IO_DEBUG_Steering : 2|8@1+ (1,-2) [-2|2] "" DBG,DRIVER
 SG_ IO_DEBUG_RPM : 10|32@1+ (1,0) [0|0] "" DBG,DRIVER
 
BO_ 107 DRIVER_DEBUG: 1 DRIVER
 SG_ IO_DEBUG_CAN_init : 0|1@1+ (1,0) [0|0] "" DBG
 SG_ IO_DEBUG_bus_off : 1|1@1+ (1,0) [0|0] "" DBG
 SG_ IO_DEBUG_DRIVER : 3|1@1+ (1,0) [0|0] "" DBG

BO_ 108 GPS_DEBUG: 1 GPS
 SG_ IO_DEBUG_CAN_init : 0|1@1+ (1,0) [0|0] "" DBG
 SG_ IO_DEBUG_bus_off : 2|1@1+ (1,0) [0|0] "" DBG
 SG_ IO_DEBUG_GPS : 3|1@1+ (1,0) [0|0] "" DBG
 SG_ IO_DEBUG_Compass : 5|1@1+ (1,0) [0|0] "" DBG

BO_ 109 BRIDGE_DEBUG: 1 BRIDGE
 SG_ IO_DEBUG_CAN_init : 0|1@1+ (1,0) [0|0] "" DBG
 SG_ IO_DEBUG_bus_off : 2|1@1+ (1,0) [0|0] "" DBG
 SG_ IO_DEBUG_Bridge : 4|1@1+ (1,0) [0|0] "" DBG 

CM_ BU_ DRIVER "The driver controller driving the car";
CM_ BU_ MOTOR "The motor controller of the car";
CM_ BU_ BRIDGE "The bridge controller of the car";
CM_ BU_ GPS    "The GPS controller of the car";
CM_ BO_ 100 "Sync message used to synchronize the controllers";
CM_ SG_ 100 DRIVER_HEARTBEAT_cmd "Heartbeat command from the driver";

BA_DEF_ "BusType" STRING ;
BA_DEF_ BO_ "GenMsgCycleTime" INT 0 0;
BA_DEF_ SG_ "FieldType" STRING ;

BA_DEF_DEF_ "BusType" "CAN";
BA_DEF_DEF_ "FieldType" "";
BA_DEF_DEF_ "GenMsgCycleTime" 0;

BA_ "GenMsgCycleTime" BO_ 100 1000;
BA_ "FieldType" SG_ 100 DRIVER_HEARTBEAT_cmd "DRIVER_HEARTBEAT_cmd";

VAL_ 100 DRIVER_HEARTBEAT_cmd 2 "DRIVER_HEARTBEAT_cmd_REBOOT" 1 "DRIVER_HEARTBEAT_cmd_SYNC" 0 "DRIVER_HEARTBEAT_cmd_NOOP" ;

Busmaster

To monitor the messages being sent on the CAN-BUS, a PCAN dongle which Preet lent each group was used to connect to the CAN Bus and monitor messages being sent. The software used to monitor and analyze the messages sent on the CAN bus was Busmaster. An image of the busmaster message window and a signal graph is shown below.

Busmaster Message Window showing the message received on the PCAN dongle

Busmaster signal graph displaying middle, left, right, and rear sensor message data

Sensor ECU

Sensor node Gitlab

The sensor and bridge controller consists of sensor module that is responsible for object detection. Nimble uses ultrasonic sensors to achieve this task. As the name suggests, an ultrasonic sensor emits ultrasonic signal or beam from its head, and on encountering an object, returns back. This technique is better known as echolocation as we used sound signals to do so. The distance of the object is calculated based on the output and this ensures object detection. The distance measured is continuously passed on to driver node through can transceiver. The driver controller further processes the distance values of all the sensors on nimble and acts in accordance with the values to achieve obstacle avoidance.

Hardware Design

We have embedded 4 sensors on Nimble. We have arranged 3 LV-MaxSonar-EZ series Maxbotix ultrasonic sensors in the front section of the car; one at right, one at left and one in the center. The fourth Ultrasonic sensor is placed at the rear end of the car. These sensors provide very short to long-range detection. It provides sonar range information from 6-inches out to 254-inches with 1-inch resolution.

sensor and SJTWO connection description

Pin specification of Ultrasonic sensors

A maxbotix sensor gives out 3 types of output- analog, RS232, and Pulse width. We have used analog output and hence, utilized on-board analog to digital converters- ADC2 (P0.25), ADC3 (P0.26), ADC4 (P1.30), and ADC5 (P1.31). To trigger all the four ultrasonic sensors, we used P0.6, P0.7, P0.8 and P0.9 of SJTWO board. The analog output is converted to digital and transmitted to the driver controller. The converted adc distance data is passed to driver by Can transceiver. P0.0 is used as CAN RX and P0.1 as CAN TX on the Sensor module.

Hardware Interface

Sensors are interfaced with combination of GPIO, ADC Pins on SJTWo board. Below is the descriptive pin layout:

Sensors pin layout
Sr. No.	SJTwo board Pin	Maxbotix sensor Pin	Function
1	ADC2-P0.25	AN(Left)	ADC input from left sensor
2	ADC3-P0.26	AN(Rear)	ADC input from rear sensor
3	ADC4-P1.30	AN(Right)	ADC input from right sensor
4	ADC5-P1.31	AN(Middle)	ADC input from middle sensor
5	P0.6	RX(Right)	Trigger for right sensor
6	P0.7	RX(Left)	Trigger for left sensor
7	P0.8	RX(Middle)	Trigger for middle sensor
8	P0.9	RX(Rear)	Trigger for rear sensor

Software Design

The sensor implementation is done in 100Hz callback function, part of the periodic callbacks module. To give an overview, all the sensors are triggered at once and then given a minimum buffer time of 30ms for the outbound signal to bounce back and get detected, thereby giving us the raw distance readings. These readings are then processed inside a buffer to send the minimum value over CAN at 20Hz. As we have used Analog output, we used the available onboard ADCs with a few changes to the ADC driver implemented by Preet. The SJTWO board has 4 ADC pins available, with P0.26, which can be configured as both an ADC and a DAC. So we configured P0.26, that is ADC3 channel into the code and modified the ADC driver accordingly. The ADC readings are in the form of raw voltage and hence are converted to distances in centimetres. To get the most accurate distance value of each sensor, we used a buffer that gives out the minimum distance reading at 20Hz. This distance is sent over CAN to the Driver Node which further processes these distances and triggers the motors accordingly. The flowchart below shows the implementation of our Sensor controller.

flowchart of sensor controller's operation

A. Initialization:

1. Initialization of sensors: As we are using onboard ADC to get voltage, we first initialize all the ADCs (ADC2, ADC 3, ADC 4, ADC 5). We then configured IOCON registers to set up all the ADCs, according to the LPC40xx datasheet.

2. Initialized Buffer and can.

B. Triggering the sensors:

1. Configured available SJTWO GPIO pins, to be connected to the sensor’s RX pin, as GPIO output. These pins will serve as trigger pins to the sensors.

2. The sensors are triggered in at 20Hz inside the 100Hz function. To do so, the trigger pin is set for 30ms and the reset.

C. Read sensor values:

We are using ADC values to obtain the distance. All the values are in the form of analog voltage and represents the number of steps in terms of voltage level. To get real voltage value from raw, it is multiplied by the ADC voltage and divided by voltage scaling defined by voltage level powering the sensors (here 3.3 V) and manufacturing scaling (Vcc/512). The distance values obtained are stored in the Circular buffer module. All the sensors have an individual buffer that collects the distance values and get the minimum of all the values.

D. CAN transmission:

The lowest distance in 'cm' of all the sensors is sent to driver controller over CAN bus. We have used CAN1 to achieve this task. The driver then coordinates the movement according to the distance value.

Technical Challenges

Issue 1: Unreliable reading when the whole RC car is being powered by one single portable battery. IR sensor, which was to mounted as the rear sensor wasn't receiving enough power to work reliably.
- Solution: We ended up switching the IR sensor to another ultrasonic sensor, which works even at 3.3V, in order to make the rear readings reliable.
Issue 2: Interference between the sensors was a major issue, wherein an obstacle on the right would make both the Right and Middle sensors to read low values.
- Future work: The best possible solution would be print sensor mounts in advance, after deciding upon the sensors to be used. This will ease the process of testing the RC car.

Motor ECU

Our Motor Controller node is responsible to control the DC and Servo motor from the RC car, and additional RPM sensor measurement to get the RPM value from each rotation so we can have control to the speed or our RC car. The motor controller logic the steering and speed will be calculated within the Driver Node Controller through the CAN bus messages. Then, the Motor Controller node will output the feedback of RPM value for the Driver node to display the RPM value through CAN bus to the Driver module. The Motor controller node will also use this RPM feedback from the sensor to maintaining the speed making sure that the car is under certain threshold of RPM value, so it won't become too fast or too slow. The CAN message function will be constantly called at 10Hz of the periodic callbacks, while the speed check for the RPM value will be call every 500 ms.

Motor node Gitlab

Hardware Design

The hardware interface details of MOTOR Module with SJOne board are given above:

Overall outlook in RC car

Overall circuit

Label	Function	Pin Connection
1	Can RX	Pin 0.0
2	Can TX	Pin 0.1
3	RPM Signal	Pin 2.6
4	Servo Motor Signal	Pin 2.1
5	DC motor Signal	PIn 2.0
20	GND	Pin GND

Hardware Interface

SERVO Motor

The direction of the RC car is dependent on the servo motor, based on various PWM signals of 10% to 20% it will steers the front wheels from right to left direction. The servo motor has 3 wires, where one is the PWM input signals, other two wires responsible to the VCC of 6V and Ground. We powered our Servo motor using the ESC output voltage from the Nickel Metal Hydride (NiMh) battery of the RC car, and the PWM signals will be generated from motor controller of P2.1 of SJtwo Board.

Servo motor

Label	Function	PWM_value
1	Left	PWM -> 15.1 - 20
2	Middle	PWM -> 15
3	Right	PWM -> 10 - 14.9

Label	Function	Pin Connection
1	VCC from NiMh 7.2V to Servo	VCC
2	Servo Signal to SJtwo	P2.1
3	GND	Pin GND

DC Motor

The DC motor is already connected with the ESC as default built-in from the RC car, the purpose of ESC (Electronic Speed Control) is to control the DC motor Using PWM signals from the controller. It also regulated (converted) the 7.4V NiMh battery power sources into stable 6V energy output for the DC motor and servo. The DC motor is similar to the Servo where it takes in 10% to 20% duty cycle of PWM signals to control the RC car Forward, Stop, and Reverse mode. One thing that's interesting is that there is certain sequence for the DC motor to go from Forward state into the Reverse state, based from the design of the ESC it is to protect the DC motor from breaking.

The sequence of the DC motor to go to Reverse is that it have to received the PWM of Reverse duty cycle for two times before it actually starting to go in reverse direction.

DC motor

ESC

Label	Function	Pin Connection
1	VCC from NiMh 7.2V to ESC	VCC
2	DC Signal from ESC	P2.0
3	GND	Pin GND

Label	Function	PWM_value
1	Left	PWM -> 15.1 - 20
2	Straight	PWM -> 15
3	Right	PWM -> 10 - 14.9

RPM Sensor

RPM sensor is the device that calculated the one single rotation per certain duration of time frame. It can be a device that used magnet to calculated one rotation or IR Optocoupler with its corresponding disk, as long as the device can successfully achieve the job of counting one rotation cycle. Our RPM sensor in mounted on the car shaft instead of the built-in RPM sensor from Traxxas, when ever the IR Optocoupler sending the signals to the P2.6 as the interrupts it will increment the rotation_count for the computation on the RPM value. The IR Optocoupler have 4 PIN, where we only used its VCC, GND, and D0 for our RC car, the VCC need power of 3.3V to 5V to properly power-up the device, and the GND should have common GND that connected all the devices, while D0 pin will goes to P2.6 in our Motor Controller.

RPM value

Label	Function	Pin Connection
1	VCC from 5V Portable Power Bank	VCC
2	RPM Signal to P2.6	D0
3	GND	Pin GND

Software Design

The dc motor and servo motor operation is fundamentally based on PWM (Pulse Width Modulation). We set the PWM frequency to 100Hz for both dc and servo motor.

Pseudo code for initializing PWM to 100Hz.

 gpio__construct_with_function(2, 0, 1); 
 gpio__construct_with_function(2, 1, 1);

 // gpio input for interrupt
 gpio__construct_as_input(2, 6);

 // gpio initialize the interrput
 gpio2__attach_interrupt(6, GPIO_INTR__RISING_EDGE, pwm_get_speed);
 lpc_peripheral__enable_interrupt(LPC_PERIPHERAL__GPIO, pwm_get_speed, NULL);

 pwm1__init_single_edge(frequency_in_hertz); // usually use 100 hz

DC Motor Flow Chart - State Machine

Servo Motor Flow Chart

RPM Flow Chart

Servo motor Pseudo Code

The servo motor is connected to the Pin 2.1 on SJTwo Board. The servo received the command of -2 to 2 from the can1 of driver node every 10 Hz, where the -2 represents full left and 0 as neutral and 2 as full right turn. Then the data from CAN bus of driver node will be process under if statement to select the respective rotation of the servo motor according to the data received from the driver logic. Under is some Pseudo logic of the function, once the rotation is finish selected it will use motor_control_status__process_data(); to choose the respective PWM of the Servo, where left would be 20 and right would 10 and 15 as neutral state of the servo motor.

 if (motor_cmd_data->MOTOR_CMD_STEERING == steer_left) {
   motor_control_status__process_data(MOTOR_STATUS_LEFT);
 } else if (motor_cmd_data->MOTOR_CMD_STEERING == steer_right) {
   motor_control_status__process_data(MOTOR_STATUS_RIGHT);
 } else if (motor_cmd_data->MOTOR_CMD_STEERING == steer_slight_left) {
   motor_control_status__process_data(MOTOR_STATUS_SLIGHTLY_LEFT);
 } else if (motor_cmd_data->MOTOR_CMD_STEERING == steer_slight_right) {
   motor_control_status__process_data(MOTOR_STATUS_SLIGHTLY_RIGHT);
 } else if (motor_cmd_data->MOTOR_CMD_STEERING == steer_straight) {
   motor_control_status__process_data(MOTOR_STATUS_STRAIGHT);
 }

DC motor Pseudo Code

The DC motor is connected to the Pin 2.0 on SJTwo Board. The DC received the command of PWM every 10 Hz, where the 20 represents full forward and 15 as neutral and 10 as full reverse. Because the value of DC motor when it is 20 or 10 would be too fast for the sensor to even react and transfer the signal to the motor node, we reduce the forward and reverse PWM as 15.5 for forward and 14.5 for reverse. The DC motor will be modify under the switch case state machine for FORWARD, REVERSE, STOP state of the DC motor. And the RPM sensor will be getting the speed of the RC car to increase or reduce the speed of the RC car in term of PWM. Below is partial code of the FORWARD state. The pwm_request_by_app will receive the speed request of from driver node in CAN1 bus, which will select and make the state change accordingly, and pwm_maintain_speed_forward(); will just be using the PWM sensor in the next section to monitor the rotation of the RC car so it doesn't be come too fast or too slow.

  if (0 >= pwm_request_by_app) {
     pwm_DC_motor(motor_speed_stop);
     pwm_servo_motor(servo_center);
     motor_value_type = MOTOR_STATUS_STOP;
     break;
   }

   pwm_maintain_speed_forward();

RPM sensor Calculation Pseudo Code

The RPM sensor is connected to the Pin 2.6 on SJTwo Board. It will received the signals from the every time it finish the single rotation. It will use interrupt to register these pulses in a 500ms time frame and then calculate the speed in m/s based on the formula:

 rotation_per_min = rotation_value * ((60s * 1000hz "1 second")/duration_time) //where the duration_time is 500ms.

Because there is some difficulty in installing the magnet RPM sensor into the RC car, we end up using the LM393 Speed Detection Sensor Module with the Type IR Optocoupler and it's respective disks for the IR Optocoupler. So within one single rotation it will received 20 rotation_count, which them we will have to divided the rotation_count we received from the interrupt by 20 to get the actual one rotation from the wheel. The equation will be the following below.

   rotation_value = rotation_count / 20;

And rotation_count will be received using code below.

 rotation_count = rotation_count + 1;
 clear_pin_interrupt2(6);

Technical Challenges

Issue 1: One of the challenges to deal with in this project on the motor node, is probably the incompatibility of the RPM sensor from Traxxas. The RC car we got even thought it is from the Traxxas it doesn't have the slot for us to put in the RPM sensor and the magnet disk.
- Solution: We end up just using the IR Optocoupler and the middle car shaft that connect from the rear motor to the front wheel. The whole isn't perfect fit so we do have to make the hole for the disk larger and use glue gun to secure the location of the IR Optocoupler.
Issue 2: Probably not the issue but more of what future work we could done to improve our current motor controller. As we run the DEMO there is overshoot problem when the RC trying to reach the checkpoints, due to not having implementation of PID controller.
- Future work: The solution would be increasing the CAN message commands of steering angle that Driver node sent to the motor node, and compute those angles from driver node to make variety of option for servo steering instead of just 5 options: slight left, left , slight right, right, and straight.

Issue 3: Another future work that we could be doing, is that we notice during our demo our RC car will stop for a bit due to going over the threshold of RPM value on the RC car.
- Future work: There are two possible solution to this issues, first one is to make the increment and decrement of the maintain_speed function smaller, so it won't over shoot the RPM value generated from the RC car. Another solution is to adjust the RPM value of the threshold, so that it can be easier for the DC motor to main it's PWM.

Geographical Controller

Geo Module Gitlab link

The geographical controller is responsible for interfacing with a GPS and Compass module in order to receive the current heading(in degrees) and the current destination in the form of GPS coordinates (in degrees, hours, minutes, seconds). It is also responsible for receiving the needed destination coordinates sent by the BRIDGE controller which are needed along with the current GPS location coordinates to calculate the destination heading angle and distance to destination and checkpoints. The current compass heading angle is also sent to the DRIVER controller such that it can be integrated into the driver logic to determine the heading angle to steer and drive towards the destination.

Hardware Design

In essence, the Geo-controller is interfaced with a GPS and Compass through UART2 and UART3, respectively. Additionally, the Geo-controller is interfaced with a CAN transceiver in order to receive and send messages from and to other nodes.

Geo Controller Hardware Design

Hardware Interface

GPS

The GPS is responsible for sending GPS NMEA sentences to the Geographical controller to parse and tokenize in order to get the current latitude and longitude in the units, degrees:hours:minutes:seconds. The sentence desired to extract the coordinates is the GPGGA sentence which contains fixed GPS coordinates. The GPS module that we used for this project was the "Ultimate GPS breakout board" from Adafruit. The module was interfaced with the UART2 port of the SJTwo LPC4078 Controller with a baud rate of 9600 and with 1 stop bit.

Ultimate GPS Breakout board from Adafruit

GPS pin layout
No.	SJTwo Controller Pin	Ultimate GPS Breakout Pin	Function
1	UART2-P2.8(TX)	RX	UART TX from SJTwo to RX port of GPS module
2	UART2-P2.9(RX)	TX	UART RX from SJTwo to TX port of GPS module
3	Power Bank VCC-5.0V	Power(Vin)	Powering gps module
4	Ground Port	GND	ground port of gps module

Compass

The compass is required to get the current heading of the RC car such that it can send the heading information from the geographical controller to the driver controller to perform destination navigation as part of the driver logic. The compass module purchased for this project was the CMPS14 compass module. This module was interfaced to the (Geographical) SJTwo controller using UART3, a baud rate of 9600, and 2-stop bits. The compass can be operated in two modes, I2C and serial(UART) mode. The compass utilized for the project was set in serial mode using UART2. Its register contents and various commands include receiving the bearing angle in 16 or 8-bit and altering the calibration settings and profiles. Additionally, the cmps14 is tilt-compensated and includes an accelerometer, gyro-meter, and magnetometer.

CMPS14 Compass Module

Compass pin layout
No.	SJTwo Controller Pin	CMPS14 Pin layout	Function
1	UART3-P4.28(TX)	RX	UART TX from SJTwo to RX port of Compass module
2	UART3-P4.29(RX)	TX	UART RX from SJTwo to TX port of Compass module
3	Vcc(3.3v)	Power(Vin)	Powering compass module
4	Ground Port	GND	ground port of compass module
5	Ground Port	Mode Pin	Compass mode pin Ungrounded(I2C) Grounded(UART)

CMPS14 Registers and Commands for Serial Mode

Compass Calibration flow-chart

Software Design and Implementation

High-level software flow of the geographical controller and periodic callbacks utilized.

Geo controller software flow chart

Periodic Callbacks 1Hz software flow chart

Periodic Callbacks 10Hz software flow chart

GPS NMEA sentence parsing and tokenization

GPS run once is called in the 10Hz periodic callback and is essentially done through obtaining a stream of (GPS NMEA sentence) bytes from the GPS module through UART, storing the stream into a line buffer FIFO. The stream of bytes are then popped to a handle line where the stream of bytes or the GPS strings are then handled and processed by checking for the $GPGGA sentence, in particular, using strstr(). If the string "$GPGGA" is found, then tokenization begins using sscanf() for the relevant information required for extraction: latitude, latitude direction, longitude, longitude direction, and the valid fix value. Before the essential information is extracted, a check must be made using the extracted valid GPS fix value. If the valid GPS fix is greater than 0 (1 or 2 are the only possibilities), then it indicates a valid GPS fix versus, otherwise, if the value is 0, then it is an invalid fix, therefore it should not extract the coordinates. If the latitude direction is South("S" or "s"), then the coordinates extracted will be multiplied by -1. Similarly, if the longitude direction is West("W" or "w"), then the extracted longitude is multiplied by -1. Manual calibration is also implemented by(in our case) adding to the latitude and longitude coordinates. This was done because the readings given to us by the GPS were very poor.

GPS Parsing software flow-chart

Calculating destination bearing angle

Calculating the destination bearing angle between the current and destination longitude and latitude coordinates was done using the formula as follows...

 Formula: θ = atan2( sin Δλ ⋅ cos φ2 , cos φ1 ⋅ sin φ2 − sin φ1 ⋅ cos φ2 ⋅ cos Δλ )
   
 where...
 θ  = destination bearing angle
 φ1 = Latitude of origin coordinate
 φ2 = Latitude of destination coordinate
 λ1 = Longitude of origin coordinate
 λ2 = Longitude of destination coordinate
 Δλ = λ2 - λ1

Calculating destination distance

The destination distance between current and destination longitude and latitude coordinates was calculated using the haversine formula.

 a = sin²(Δφ/2) + cos φ1 ⋅ cos φ2 ⋅ sin²(Δλ/2)
 c = 2 ⋅ atan2( √a, √(1−a) )
 d = R ⋅ c
 
 where...
 R = earth's radius = 6,371,000 meters
 d = distance between current and destination gps coordinates
 c = angular distance in radians
 a = is the square of half the chord length between the points.

Testing Area and GPS Navigation Checkpoint algorithm

The test are we chose was in a small intersection in a suburban neighborhood. The checkpoints set were set in a manner that would demonstrate that the RC car can navigate through the intersection without cutting through corners through sidewalks as a real would do so. The Longitude and Latitude coordinates were taken from google maps and used to insert into a static const struct array. The algorithm must iterate through the array of checkpoints and determine which point would be navigated towards next based on how close the point is to the car and at the same time how close the point is to the destination.

Checkpoints set on google maps

Checkpoint software design flow-chart

Technical Challenges

Issue 1: Probably one of the most difficult challenges to deal with in this project was the inaccuracy of the GPS module. The default readings of this GPS module would be read were not even remotely close to its actual location.
- Solution: Although we did not fully fix this issue, the method that we dealt with the poor accuracy was to implement manual calibration with respect to the actual location of the module using google maps, and either adding or subtracting an offset to the GPS coordinates received from the GPS module.

Issue 2: Calibration of the compass was another issue. Each time the compass module would boot up, the readings of the heading angle would be off by a considerable amount.
- Solution: The solution to solve this was to send calibration commands to the compass module through button press. Helpful commands to send to the compass was erasing the calibration profile and setting default calibration settings.

Issue 3: The checkpoints set using google maps for our area used for testing were shifted when doing physical testing with the RC car. This was due to the poor accuracy of the GPS despite our efforts in performing some manual calibration of the GPS.
- Solution: The solution, although not perfect, was to set an offset to the original checkpoints such that the newly shifted coordinates would reflect the checkpoints originally set using google maps.

Issue 4: Another issue encountered was the failure of connecting to the mobile application in time of the demo.
- Solution: The only solution we had was to hardcode GPS coordinates for the destination instead.

Communication Bridge Controller

Bridge controller GitLab link

note: The bridge and sensor controller are separate in the report to provide clarity of the modules used in each node. In reality, the bridge and sensor nodes are implemented together in one SJTWO controller.

The bridge controller is responsible for receiving and sending data from and to the mobile application of this project. For this project, the bridge and sensor nodes are controlled by one SJTWO microcontroller.There are several ways to make affective communication between SJTWO and mobile application such as Zigbee, WIFI and Bluetooth. Nimble bases its communication with mobile app through HC-05 bluetooth module. The bridge controller is interfaced with a bluetooth module in order to connect to the mobile application. Its main purpose is to receive GPS destination coordinates set by the user of the mobile app and send the destination to the geographical controller to be processed and determine a destination heading for the RC car to navigate to. In addition, the bridge controller may receive debug information such as sensor, compass, motor rpm, and current GPS coordinates to be sent and displayed on the mobile app.

Hardware Design

The HC-05 modules are very clever pieces of hardware, as they translate incoming Bluetooth communication to serial data. So once configured this gives the tinkerer the possibility to achieve serial communication over Bluetooth.

HC-05 pin description

Interfacing Bluetooth with SJTWO board

The HC-05 acts transparently, meaning that you just communicate with the serial port it is connected to and the module then sends/receives via Bluetooth. A typical operating voltage of hc-05 is between 4-6V and has nominal range of 100m. The communication was uart based and operates at 115200 baud rate.The ultrasonic sensors and bridge resides on the same controller board. The pin connection description of the module is shown in the figure below. The TX and RX end are connected to P2.48 and P2.49 of SJTWO board which is RX3 and TX3. The same controller also houses 4 sensors and the the communication takes place via can transceiver. Can1 is used to transmit the values to other modules that can further act upon data.

Software Design and Implementation

The software for this part was a Bluetooth module for the SJ2 board. The data sent from the mobile application will be parsed and sent to the geographical controller using the dbc encode and send method. Additionally, sensor, compass, and motor messages would be decoded to be received from their respective controllers. This data would then be parsed by python in the main app to send to the(mobile app) front end.

Bridge controller software flow-chart

Bridge controller periodic callback 1Hz flow-chart

Bridge controller periodic callback 10Hz flow-chart

Bluetooth run once

The software design is similar to the GPS run once in terms of absorbing data from UART and adding the bytes to a line buffer. The differences lie in tokenizing the gps_line that is being sent from the mobile app. The data being sent is the GPS latitude and longitude itself which is delimited by a " : ". We can parse the latitude and longitude as well as the directions easily by iterating through the gps line by the length of the coordinates and storing the respective coordinates by checking whether the delimiter, ":" has been detected or not.

Bluetooth receive software flow-chart

Bluetooth send

Sending data to the HC-05 module is done by using the uart__put() method provided in the sjtwo-c development environment from Preet.

Bridge controller software flow-chart

Technical Challenges

Issue 1: Bluetooth module - the main problem with this was trying to get the parts to print on Hercules after sending data from the App.
- Solution: This issue was resolved once the stop bits were figured out.

Issue 2: Data formation - a problem with this was getting the correct way to send data to the Python back end and then parsing the information.
- Solution: This was resolved by making the data sent in a certain way.

Driver Controller & LCD

Driver Module Gitlab link

The driver controller is responsible for performing driver logic which will execute both obstacle avoidance and destination navigation. Additionally, an LCD display screen is used as a dashboard to provide the user with meaningful information such as sensor values, GPS destination set, compass bearing degree, distance to the destination, and speed information of the car.

LCD Display located at the rear of the car

Close-up of LCD display showing sensor, current heading degree ,destination heading degree, distance, and speed information

Hardware Design

The only hardware that the driver is required to be interfaced with, is the LCD display. The LCD display used for this project is a 20x4 LCD screen and is interfaced using I2C with the aid of an I2C backpack which came with the display.

Driver Controller Hardware Design

Hardware Interfacing

LCD

20x4 LCD Display

SJTWO and LCD Display Interfacing
No.	SJTwo Controller Pin	LCD I2C backpack Pin	Function
1	VCC-5V Power Bank	Vin	Power pin for LCD
2	SDA-P0.10	SDA	SDA pin
3	SCL-P0.11	SCL	SCL pin
4	Ground Port	GND	Ground pin

Software Design and Implementation

Driver controller software flowchart

Driver Periodic callback 1Hz software flow chart

Driver Periodic 10Hz software flow chart

Driver Periodic 20Hz software flow chart

Driver Logic

Obstacle Avoidance

Obstacle avoidance is implemented first by setting a comfortable detection threshold range(in cm) for the sensors. These threshold values determine whether an action must be taken if a sensor detects an object equal to or less than the allowed threshold. For example, if the left sensor detects an object that is closer than or equal to a threshold of 30 cm, and if the right and middle sensor do not, then the RC car should steer right to avoid the detected object on the left. If no object is detected by the front three sensors, then the car should resume GPS navigation. When an action is determined, the driver controller sends motor commands(through CAN) to the motor controller to update the speed and/or steering of the RC car.

The code snippet below shows object avoidance for far front objects or when the front sensor does not detect any objects nearby, so the left and right sensor values are compared against each other to determine whether a slight left or slight right turn should be taken when avoiding an object on the left or right.

 static void driver_logic__get_motor_commands_for_far_away_front_object(void) {
 
 if ((driver_SENSOR_SONAR.SENSOR_SONARS_right <= sensor_threshold_mid) &&
     (driver_SENSOR_SONAR.SENSOR_SONARS_left > sensor_threshold_mid)) {
   driver__update_motor_cmd(MOTOR_STEER_CMD_slight_left, MOTOR_SPEED_CMD_forward);
 
 } else if ((driver_SENSOR_SONAR.SENSOR_SONARS_left <= sensor_threshold_mid) &&
            (driver_SENSOR_SONAR.SENSOR_SONARS_right > sensor_threshold_mid)) {
   driver__update_motor_cmd(MOTOR_STEER_CMD_slight_right, MOTOR_SPEED_CMD_forward);
                                       .
                                       .

Driver Logic software flow-chart

Destination Navigation

The navigation logic implemented within the driver logic of the driver controller is responsible for having the RC car steer towards the destination. This is done by updating the motor steering commands to turn in the direction such that the current heading of the RC car matches the destination bearing angle that is calculated and sent from the geographical controller. Additionally, the navigation logic should be implemented in such a way that it does not interfere with the obstacle avoidance such that avoiding obstacles on the way to the destination is still the highest priority. Lastly, a complimentary angle to the current heading angle is calculated to help determine whether it is better to steer right or left when comparing the current and destination heading angles.

GPS Navigation logic example

GPS Navigation driver logic software flow chart

The code snippet below shows a partial implementation of the GPS navigation in the driver logic. First, if the car is within 3 meters of the destination, then the car will stop as it has arrived at its destination. If not, it will then go on to check the cases when the current heading angle is equal to the destination angle and if so, it should continue straight towards the destination. The inner if() check statements check whether if the current heading is greater than or equal to 180 degrees. If so, it will then compare the current and complimentary heading with the destination heading angle and either turn slight left or slight right if the right conditions are met.

 if (distance_to_destination <= 3.0) {
   driver__update_motor_cmd(MOTOR_STEER_CMD_straight, MOTOR_SPEED_CMD_stop);
 } else {
   if (current_heading == destination_bearing) {
     driver__update_motor_cmd(MOTOR_STEER_CMD_straight, MOTOR_SPEED_CMD_forward);
   } else if (current_heading >= 180) {
     if (destination_bearing > current_heading || destination_bearing < current_heading_compliment) {
       driver__update_motor_cmd(MOTOR_STEER_CMD_slight_right, MOTOR_SPEED_CMD_forward);
     } else if (destination_bearing < current_heading || destination_bearing > current_heading_compliment) {
       driver__update_motor_cmd(MOTOR_STEER_CMD_slight_left, MOTOR_SPEED_CMD_forward);
     }
                                              .
                                              .

LCD Display

The LCD display for this project displays sensor values, compass heading data, distance to destination, destination bearing angle, and the RPM value. The first and second row of the LCD contains the sensor values, the middle(M), rear(Rr), left(L), and right(R) sensors. The third row displays the compass(CMP)heading and the distance to destination in meters(m). Lastly, the fourth row contains the destination bearing angle(BRG) and the revolutions per minute(RPM) value of the car motor speed.

LCD debug information: Middle(M) Rear(Rr) Left(L) Right(R) sensor values, Compass heading(CMP), Distance-to-destination(m), Destination-bearing-angle(BRG), and RPM motor value(RPM)

Initialization

The LCD is first reset to clear the screen of contents on startup of the RC car and then initialized to begin updating information on the display. The LCD is initialized by sending a series of commands before writing characters to the display. Commands to enable interfacing mode to 4-bit mode is done first. The display is then cleared and the cursor is set to autoincrement such that when a character is written to the LCD, the cursor will automatically increment to the next space for the next character to be written. Lastly, the LCD will start at the first row(LINE 1). Additionally, a delay must be added for the commands to successfully be sent to the LCD.

 void LCD__init(void) {
 
 LCD__command_to_LCD(FOUR_BIT_MODE);
 
 LCD__command_to_LCD(DISPLAY_AND_CURSOR);
 
 LCD__command_to_LCD(CLEAR_SCREEN);
 
 LCD__command_to_LCD(AUTOINCREMENT_CURSOR);
 
 LCD__command_to_LCD(LINE1);
 
 delay__ms(5);
 }

Updating the LCD Status

Updating the status of the display was called in the 1Hz periodic callback. The function takes the struct values of each debug information and is put into a buffer to be written onto the LCD display. Before writing each debugging information, for example, the middle and left sensor values, a command must be sent to indicate the row in which the values should be written. This is done for all pieces of debug information.

 void LCD_status__display_on_screen(void) {
 char lcd_buffer[20];
 LCD__command_to_LCD(CLEAR_SCREEN);
 
 LCD__command_to_LCD(LINE1);
 sprintf(lcd_buffer, "M: %i", lcd_sensor.SENSOR_SONARS_mid);
 LCD__string_to_LCD(lcd_buffer);
 
 LCD__command_to_LCD(LINE1 + 10);
 sprintf(lcd_buffer, "L: %i", lcd_sensor.SENSOR_SONARS_left);
 LCD__string_to_LCD(lcd_buffer);
 
 LCD__command_to_LCD(LINE 2 );
 sprintf(lcd_buffer, "Rr: %i", lcd_sensor.SENSOR_IR_rear);
 LCD__string_to_LCD(lcd_buffer);
 
 LCD__command_to_LCD(LINE 2 + 10);
 sprintf(lcd_buffer, "R: %i", lcd_sensor.SENSOR_SONARS_right);
 LCD__string_to_LCD(lcd_buffer);
               .
               .
               .

LCD status update software flow-chart

Technical Challenges

Issue 1: The first issue with the driver controller was testing obstacle avoidance in a physical test with the RC car. This issue was mostly trial and error when trying to set well-balanced sensor thresholds.
- Solution: Trial-and-error in doing physical tests to see how the RC car reacts and to determine what sensor value threshold would be adequate enough to detect objects far enough such that the RC car has enough time to react.

Issue 2: Another issue that we faced was updating the LCD display. Since the commands that are required to be sent to the LCD require some delays, updating the LCD in a periodic call in the 10Hz or above would end up resetting the micro-controller.
- Solution: Putting the LCD display update function was put into the 1Hz periodic callback.

Issue 3: Fitting all information on the LCD display was difficult considering the size limit of the 20x4 LCD.
- Solution: Applying short but meaningful abbreviations to the labels of each debug information onto the display. A better solution would be is to print multiple status screens for different forms of information.

Mobile Application

Mobile App Gitlab link

Software Design

The software's main front end code was written in Javascript while the backend was written in Python flask to send and receive data from the microcontroller to the app. The methods of sending GPS coordinates from the app to the microcontroller was using a location's address or a point and click map from google. To receive the data from the microcontroller, the data had to be sent from the Bluetooth module in a specific way such that python could parse through the data and then separate it into sensor and sensor value. The sent data would be picked up every five seconds so that this would allow for the user to send data without having sockets closing from the code before the data could send.

Technical Challenges

The main technical challenge was learning Javascript without having any prior experience in coding Javascript, but to do this lots of research was done on how to make classes, send data to the backend, and how to make the webpage dynamic in updating information. Another challenge was making the Bluetooth module work with the microcontroller for this class. The difficulties in this were that the Bluetooth module was made for an Arduino so the settings had to be modified so that it could work with other microcontrollers by modifying the Baud rate and stop bits. The last technical challenge was working with a python backend. The reason for this is that there is a method that was needed to get information from the front end that was not familiar to the normal python, instead of GET and POST methods had to be researched to get the data and then printed on the webpage instead of using a simple print function.

Javascript and React-framework: The challenge in this was learning a new language, but to resolve this many youtube videos were watched and forums were read to learn how to program in a new language.
Bluetooth module development: This was difficult because the stop bits had to be played around with until the right one was selected, but after changing the values around the proper setup was made after a while
Flask and python backend: The problems with this were programming in an unconventional python way, instead, it dealt with POST and GET methods to gather front end data and if there were errors then the simple print functions couldn't be used to find the values of variables but they had to be printed onto a second webpage. To fix this, many tries were taken to try and get the data from the front end as well as finding a way to find the data values easier.

Conclusion

Nimble was a great opportunity to learn test-driven design strategies, which helped lower the amount of time troubleshooting issues. It also taught us much about using Git for version control. The project also gave us experience working with embedded systems technologies such as the following:

Can Bus (Including Bus Master):
- Using the CAN bus to communicate with multiple different devices instead of using SPI and UART, which is something totally new.
- How to debug and understand the CAN message using the BusMaster.
- Modifying the DBC to get different CAN messages, and data that transfer in-between different controller nodes.
Sensor:
- How to properly initialize the sensor and transfer the creating the driver logic-based from the data of the sensor.
GPS & Compass:
- NMEA data packets and what to expect for the GPS module. It is also interesting on how to initialize and calibrate the compass and GPS
Unit Testing:
- We learned the Unity and CMOCK framework, and how to unit-test our code modules which sped up the development of the components of the project. In particular, the GPS and Compass were thought to be the hardest to get working, but with an early start and unit-testing, these modules faced little issues to get working. The only difficulties as mentioned before was the calibration and accuracy.
- We believe that this is by far the most useful and interesting experience that we have encountered this semester. Although we're still not experts on writing flawless unit-tests, it doesn't change the fact of how incredibly revolutionary and useful it was during our project.
GIT:
- We learned all the basic go GIT and it helps us collaborate on the different modules virtually without physical meeting. (Because of Corona Virus)

Although there were some problems encountered while doing this project, we were able to finish the majority of the basic tasks required of the project. Unfortunately, we were not able to implement the mobile application as a requirement due to some issues encountered with the connectivity of the Bluetooth module which occurred in the last week of the project. Additionally, because of the COVID-19 outbreak, classes had to be conducted through google hangouts for the rest of the semester. The outbreak also made it difficult to meet physically with teammates which made it difficult to not only integrate and test the RC car, but it also reduced involvement in the project of every teammate. Despite these shortcomings of the project, the overall experience was fun and interesting. The class and project helped us learn a TON of new concepts and skills that will prove valuable in the future and industry.

Project Video

Team Nimble RC Car video link

Project Source Code

Project Nimble Gitlab link

Advice for Future Students

Advice 1: Always make sure the teammate you choose is responsible since teammate is the most important part of this group project. If any teammate is not responsible, make sure you pursue them and keep track of their progress. Otherwise, you will end up finishing their lack of progress. Also, make sure you get your teammates' contact information, besides slack, like phone or text messages.

Advice 2: Set an earlier deadline and make sure your teammates finish before the deadline. There should be no tolerance because this project will be more difficult when there is a lack of contribution from team members. If there are no strong leaders within your team, the result of your project will not be great. Also, assign important tasks, like GPS and Mobile application, to someone with the most knowledge and reliability, since those two are by far the most difficult part of the RC car. A rough draft of the mobile application should be highly considered early on. Especially if nobody in your team has experience in mobile app development. It is HIGHLY recommended to refer to the previous semesters' team to get a GOOD LOOK of Preet's expectations .

Advice 3: Make sure the GPS modules you purchase is over $90 where it is more reliable. DO NOT purchase the GPS our team purchase, where has is shown significant failure. Make sure you guys spend more money on the GPS module as it is a critical component of the project.

Advice 4: Plan a backup in case something goes wrong. Always make sure you give enough time to polish your final Project. This includes having enough time to make a good enclosure or packaging for the RC car. Additionally, it's good to adapt to a change of situation if needed. In our case, due to the COVID-19 outbreak, group meetings were scheduled over google hangout instead of in-person.

Advice 5: Overall this is an interesting class project, where you learn a lot. Please take advantage of this project by asking Preet lots of questions. Again, the teammates you choose will be important. DO NOT wait until the second lecture to form your team. Make sure you form your team during the first two weeks of the lecture!

Advice 6: Make sure everyone in your group shows up in the Preet's Lectures because Preet provided a lot of useful information related to our major and project. Missing one day of lectures can cause 1 week of set back for your project.

Advice 7: Make sure to read through previous reports before finalizing on the sensors to be used. Buy a few additional sensors as a backup. Make sure you solder the pins with keeping their eventual placement on the RC car in mind. Desoldering the pins on the ultrasonics is a really tedious job, so save yourself some time.

Acknowledgement

Preet for introducing us to new concepts/technical skills and continuing to teach us innovative practices that would not be taught in the industry.

ISAs Aakash Chitroda and Vignesh Kumar for being great ISAs in guiding and keeping us on track throughout the semester!

Previous 243 groups who provided great wiki reports of their projects and have given us advice and tips which helped us with our project.

References

website used to calculate destination distance(haversine formula) and the destination heading angle:bearing angle and distance link

Latitude and Longitude Finder lat and long finder

google maps for setting checkpoints google maps

@@ Line 1: / Line 1: @@
+[[File:CMPE243_S20_Nimble_logo.jpg|thumb|600px|caption|right|Nimble Logo]]<BR/>
 == Nimble Autonomous RC Car==
@@ Line 36: / Line 37: @@
 == Team Members & Responsibilities ==
-<Team Picture>
+[[File:CMPE243_Nimble_Member1_pic.jpg|200px|middle| '' Tanmay'']]
 * '''Tanmay Chandavarkar [https://www.linkedin.com/in/tanmay-c-a56790a0/ LinkedIn] [https://gitlab.com/tanmayhc Gitlab]<br> '''
@@ Line 43: / Line 45: @@
 **  '' Wiki ''
-* '''Yuming Cheng [ LinkedIn] [https://gitlab.com/rzming56 Gitlab]<br> '''
+[[File:CMPE243_Nimble_Member_Yuming_pic.png|200px|middle| '' Yuming Cheng'']]
-** ''GPS Module''
-** ''Master Module''
+* '''Yuming Cheng [https://gitlab.com/rzming56 Gitlab]<br> '''
 ** ''Motor Module''
-** ''LCD display''
+*** ''GPS Module''
-** ''RC Integration and testing''
+*** ''Driver Module (Master Module)''
+*** ''LCD display''
+*** ''RC Integration and testing''
 **  '' Wiki ''
+[[File:Ellis1.jpg|200px|middle| '' Ellis Makwana'']]
 * '''Ellis Makwana [https://www.linkedin.com/in/ellis-makwana-1b9026192/ LinkedIn] [https://gitlab.com/EllisMakwana Gitlab]<br> '''
@@ Line 55: / Line 61: @@
 **  '' Wiki ''
-* '''Naeem Mannan [ LinkedIn] [https://gitlab.com/nmannan97 Gitlab]<br> '''
+* '''Naeem Mannan [https://gitlab.com/nmannan97 Gitlab]<br> '''
 **  '' Wiki ''
 ** ''Mobile Application''
+** ''Bridge Controller ''
-* '''Francesco Vescio [ LinkedIn] [https://gitlab.com/francesco.vescio Gitlab]<br> '''
+* '''Francesco Vescio [https://gitlab.com/francesco.vescio Gitlab]<br> '''
 **  '' Wiki ''
 **  '' Code Review ''
+[[File:Lawrence Wan.JPG|270px|'' Lawrence'']]
 * '''Lawrence Wan [https://www.linkedin.com/in/lawrence-wan-0a432b17a/ LinkedIn] [https://gitlab.com/Lawrence.Wan Gitlab]<br> '''
-** ''Driver Module''
 ** ''GPS Module''
-** ''Motor Module''
+** ''Driver Module (Master Module)''
-** ''LCD display''
+*** ''Motor Module''
-** ''Sensor Module''
+*** ''LCD display''
+*** ''Sensor Module''
+*** ''Bridge Module''
 ** ''RC Integration and testing''
 **  '' Wiki ''
@@ Line 137: / Line 147: @@
 *<font color="red">''' 3/24/2020 -> Anonymous Reviews  '''</font>
 ||
-*<font color="orange">'''Complete  '''</font>
+*<font color="green">'''Complete '''</font>
 *<font color="green">'''Complete '''</font>
-*<font color="orange">'''Complete  '''</font>
+*<font color="green">'''Complete '''</font>
-*<font color="orange">'''Complete  '''</font>
+*<font color="green">'''Complete '''</font>
 *<font color="green">'''Complete '''</font>
 *<font color="green">'''Complete '''</font>
@@ Line 156: / Line 166: @@
 *<font color="brown">'''Configure bluetooth module name as Nimble using Communication Mode. (Naeem)'''</font>
 *<font color="brown">'''Add a TextView for displaying the Bluetooth connection status in mobile App.(Naeem)'''</font>
-*<font color="fire">'''Explore UI designing of LCD. (Francesco)'''</font>
+*<font color="fire">'''Explore UI designing of LCD. (Lawrence & Yuming &Naeem)'''</font>
 *<font color="red">'''4/01/2020 -> Updated Overall DBC file. '''</font>
 *<font color="red">'''4/01/2020 -> Update the wiki schedule. '''</font>
@@ Line 163: / Line 173: @@
 ||
 *<font color="green">'''Complete '''</font>
-*<font color="orange">'''Complete  '''</font>
+*<font color="green">'''Complete '''</font>
-*<font color="orange">'''Complete  '''</font>
+*<font color="green">'''Complete '''</font>
-*<font color="orange">'''Complete '''</font>
+*<font color="green">'''Complete '''</font>
-*<font color="orange">'''Complete  '''</font>
+*<font color="green">'''Complete '''</font>
-*<font color="orange">'''Complete  '''</font>
+*<font color="green">'''Complete '''</font>
-*<font color="orange">'''Complete  '''</font>
+*<font color="green">'''Complete '''</font>
-*<font color="orange">'''Complete  '''</font>
+*<font color="green">'''Complete '''</font>
-*<font color="orange">'''Complete  '''</font>
+*<font color="green">'''Complete '''</font>
-*<font color="orange">'''Complete  '''</font>
+*<font color="green">'''Complete '''</font>
-*<font color="orange">'''Complete  '''</font>
+*<font color="green">'''Complete '''</font>
 *<font color="green">''' Complete '''</font>
 *<font color="green">''' Complete '''</font>
-*<font color="orange">'''Complete  '''</font>
+*<font color="green">'''Complete '''</font>
-*<font color="orange">'''Complete  '''</font>
+*<font color="green">'''Complete '''</font>
 |-
 | '''6''' || '''10 April 2020'''|| '''16 April 2020'''||
-*<font color="FUCHSIA">'''Implement basic obstacle avoidance algorithm based on sensor data and test the same.'''</font>
+*<font color="FUCHSIA">'''Implement basic obstacle avoidance algorithm based on sensor data and test the same. (Lawrence & Yuming)'''</font>
 *<font color="green">'''Continue testing motor driver via commands from CAN bus.'''</font>
-*<font color="green">'''Build in speed steps to reverse motor for reverse to work correctly.'''</font>
+*<font color="green">'''Build in speed steps to reverse motor for reverse to work correctly. (Yuming)'''</font>
-*<font color="FUCHSIA">'''Mount all the sensors and test for any dead band and modify their positions for maximum coverage.'''</font>
+*<font color="FUCHSIA">'''Mount all the sensors and test for any dead band and modify their positions for maximum coverage.(Lawrence & Yuming)'''</font>
-*<font color="FUCHSIA">'''Integrate the fusion of LIDAR and Ultrasound sensor to get overall feedback from all the directions.'''</font>
+*<font color="FUCHSIA">'''Integrate the Ultrasound sensor to get overall feedback. (Tanmay & Ellis)'''</font>
-*<font color="green">'''Develop algorithm to avoid obstacles and plan the car's further navigation path.'''</font>
+*<font color="green">'''Develop algorithm to avoid obstacles and plan the car's further navigation path. (Lawrence & Yuming) '''</font>
-*<font color="FUCHSIA">'''Complete final prototype of the obstacle avoidance feature.'''</font>
+*<font color="FUCHSIA">'''Complete final prototype of the obstacle avoidance feature. (Lawrence & Yuming)'''</font>
-*<font color="orange">'''Calibrate Compass Module. Develop code for Compass module communication over CAN.'''</font>
+*<font color="orange">'''Calibrate Compass Module. Develop code for Compass module communication over CAN. (Lawrence)'''</font>
-*<font color="green">'''Test Run the Motors driven by wheel feedback and sensors, Basic obstacle avoidance.'''</font>
+*<font color="green">'''Test Run the Motors driven by wheel feedback and sensors, Basic obstacle avoidance. (Lawrence & Yuming) '''</font>
 *<font color="red">'''4/16/2020 -> Update the wiki schedule. '''</font>
 ||
@@ Line 202: / Line 212: @@
 |-
 | '''7''' || '''17 April 2020'''|| '''23 April 2020'''||
-*<font color="orange">'''Configure GPS device baud rate and interface it with SJOne board using UART.'''</font>
+*<font color="orange">'''Configure GPS device baud rate and interface it with SJOne board using UART. (Lawrence)'''</font>
-*<font color="orange">'''Send and receive current location, destination and checkpoint coordinates to and from App and Geo module via BRIDGE.'''</font>
+*<font color="orange">'''Send and receive current location, destination and checkpoint coordinates to and from App and Geo module via BRIDGE.(Lawrence)'''</font>
 *<font color="FUCHSIA">'''Calibrate sensors readings and work on filtering algorithm with Master & Sensor'''</font>
-*<font color="fire">'''Begin work on LCD to show vehicle live status(speed, fuel-status, obstacles, distance to destination etc.) in a GUI.'''</font>
+*<font color="fire">'''Begin work on LCD to show vehicle status(RPM speed, Sensor data, GPS & compass etc.) (Lawrence & Yuming)'''</font>
-*<font color="FUCHSIA">'''Finish implementing speed control on motor (to make sure requested speed is met based on RPM read).'''</font>
+*<font color="FUCHSIA">'''Finish implementing speed control on motor (to make sure requested speed is met based on RPM read).(Yuming) '''</font>
-*<font color="green">'''Work on Car reversing using Motor Controllers.'''</font>
+*<font color="green">'''Work on Car reversing using Motor Controllers.(Lawrence & Yuming)'''</font>
-*<font color="purple">'''Integrate all modules with the Master to test the data flow.'''</font>
+*<font color="purple">'''Integrate all modules with the Master to test the data flow. (Lawrence & Yuming)'''</font>
-*<font color="green">'''Validation & Verification of obstacle avoidance, steering logic with rear sensor inputs and reversing.'''</font>
+*<font color="green">'''Validation & Verification of obstacle avoidance, steering logic with rear sensor inputs and reversing. (Lawrence & Yuming)'''</font>
-*<font color="orange">'''Start incorporating GEO Controller information to Master module Steering logic.'''</font>
+*<font color="orange">'''Start incorporating GEO Controller information to Master module Steering logic.(Lawrence)'''</font>
-*<font color="maroon">'''Decide, implement and test data exchange between Geo Controller and BRIDGE.'''</font>
+*<font color="maroon">'''Decide, implement and test data exchange between Geo Controller and BRIDGE.(Lawrence)'''</font>
-*<font color="orange">'''Calculate and send simple bearing angle and destination status on CAN to figure out initial challenges.'''</font>
+*<font color="orange">'''Calculate and send simple bearing angle and destination status on CAN to figure out initial challenges. (Lawrence)'''</font>
-*<font color="brown">'''Add a Google Map for setting the car's destination.'''</font>
+*<font color="brown">'''Add a Google Map for setting the car's destination. (Naeem)'''</font>
-*<font color="brown">'''Send car location to app and check points received to Geo module.'''</font>
+*<font color="brown">'''Send car location to app and check points received to Geo module. (Naeem)'''</font>
-*<font color="maroon">'''Verify the stringent requirement of Start-up Sync, Periodic heart-beat messages.'''</font>
+*<font color="red">'''DEMO video: 4/21/2020 -> Progress report 1 (Lawrence & Yuming) '''</font>
-*<font color="red">'''4/23/2020 -> Update the wiki schedule and the git repo. '''</font>
 ||
-*<font color="red">''' Not Started Yet '''</font>
+*<font color="green">'''Complete '''</font>
-*<font color="red">''' Not Started Yet '''</font>
+*<font color="green">'''Complete '''</font>
-*<font color="red">''' Not Started Yet '''</font>
+*<font color="green">'''Complete '''</font>
-*<font color="red">''' Not Started Yet '''</font>
+*<font color="green">'''Complete '''</font>
-*<font color="red">''' Not Started Yet '''</font>
+*<font color="green">'''Complete '''</font>
-*<font color="red">''' Not Started Yet '''</font>
+*<font color="green">'''Complete '''</font>
-*<font color="red">''' Not Started Yet '''</font>
+*<font color="green">'''Complete '''</font>
-*<font color="red">''' Not Started Yet '''</font>
+*<font color="green">'''Complete '''</font>
-*<font color="red">''' Not Started Yet '''</font>
+*<font color="green">'''Complete '''</font>
-*<font color="red">''' Not Started Yet '''</font>
+*<font color="green">'''Complete '''</font>
-*<font color="red">''' Not Started Yet '''</font>
+*<font color="green">'''Complete '''</font>
-*<font color="red">''' Not Started Yet '''</font>
+*<font color="green">'''Complete '''</font>
-*<font color="red">''' Not Started Yet '''</font>
+*<font color="green">'''Complete '''</font>
-*<font color="red">''' Not Started Yet '''</font>
+*<font color="green">'''Complete '''</font>
-*<font color="red">''' Not Started Yet '''</font>
 |-
 | '''8''' || '''24 April 2020'''|| '''30 April 2020'''||
-*<font color="fire">'''Testing & Validation of the LCD UI and display run time vehicle status and looking forward for feedback from team if any.'''</font>
+*<font color="fire">'''Testing & Validation of the LCD and display vehicle status. (Lawrence & Yuming)'''</font>
-*<font color="orange">'''Improve & Validate Navigation logic with multiple checkpoints, bearing angle and destination information.'''</font>
+*<font color="orange">'''Improve & Validate Navigation logic with multiple checkpoints, bearing angle and destination information. (Lawrence)'''</font>
-*<font color="orange">'''Identify and mitigate GPS locking, Location Accuracy and Number of Satellite-In-View coming.'''</font>
+*<font color="orange">'''Identify and mitigate GPS locking, Location Accuracy and Number of Satellite-In-View coming. (Lawrence)'''</font>
-*<font color="orange">'''Validate Accuracy of Compass Calibration with iPhone Compass.'''</font>
+*<font color="orange">'''Validate Accuracy of Compass Calibration with iPhone Compass. (Lawrence & Yuming)'''</font>
-*<font color="purple">'''Determine and add DBC Changes and finalized.'''</font>
+*<font color="purple">'''Determine and add DBC Changes and finalized. (Lawrence)'''</font>
-*<font color="orange">'''Implement the steering logic with bearing angle and status provided by GEO-Module.'''</font>
+*<font color="orange">'''Implement the steering logic with bearing angle and status provided by GEO-Module. (Lawrence & Yuming)'''</font>
-*<font color="brown">'''Consistently Communicate current car location to App, get check points from App and relay them to Geo module.'''</font>
+*<font color="MAROON">'''Send additional vehicle status information from can bus to the App for display. (Naeem)'''</font>
-*<font color="MAROON">'''Send additional vehicle status information from can bus to the App for display.'''</font>
+*<font color="green">'''Field test and check for obvious issues in obstacle avoidance, navigation, maintaining speed (up/down hill). (Lawrence & Yuming) '''</font>
-*<font color="brown">'''Send the request to Google for getting the checkpoints(use the Google Maps Directions API).'''</font>
+*<font color="#808080">'''Update Wiki with new details and information. '''</font>
-*<font color="green">'''Field test and check for obvious issues in obstacle avoidance, navigation, maintaining speed (up/down hill).'''</font>
+*<font color="red">'''DEMO video: 4/28/2020 -> Progress report 2 (Lawrence & Yuming) '''</font>
-*<font color="black">'''Provide feed backs to each team on identified short comings.'''</font>
-*<font color="#808080">'''Update Wiki with new details and information.'''</font>
-*<font color="orange">'''DEMO: GPS driving'''</font>
 ||
-*<font color="red">''' Not Started Yet '''</font>
+*<font color="green">'''Complete '''</font>
-*<font color="red">''' Not Started Yet '''</font>
+*<font color="green">'''Complete '''</font>
-*<font color="red">''' Not Started Yet '''</font>
+*<font color="green">'''Complete '''</font>
-*<font color="red">''' Not Started Yet '''</font>
+*<font color="green">'''Complete '''</font>
-*<font color="red">''' Not Started Yet '''</font>
+*<font color="green">'''Complete '''</font>
-*<font color="red">''' Not Started Yet '''</font>
+*<font color="green">'''Complete '''</font>
-*<font color="red">''' Not Started Yet '''</font>
+*<font color="green">'''Complete '''</font>
-*<font color="red">''' Not Started Yet '''</font>
+*<font color="green">'''Complete '''</font>
-*<font color="red">''' Not Started Yet '''</font>
+*<font color="green">'''Complete '''</font>
-*<font color="red">''' Not Started Yet '''</font>
+*<font color="green">'''Complete '''</font>
-*<font color="red">''' Not Started Yet '''</font>
-*<font color="red">''' Not Started Yet '''</font>
-*<font color="red">''' Not Started Yet '''</font>
 |-
 | '''9''' || '''1 May 2020'''|| '''7 May 2020'''||
 *<font color="black">'''FIELD TESTING - CRITICAL WEEK '''</font>
-*<font color="blue">'''Implement turning indicators, break lights and head light.'''</font>
+*<font color="green">'''Check for Corner cases for steering logic under various conditions and locations. (Lawrence & Yuming)'''</font>
-*<font color="green">'''Check for Corner cases for steering logic under various conditions and locations.'''</font>
+*<font color="orange">'''Analyse field test results for GPS and CMPS and work on it if required. (Lawrence)'''</font>
-*<font color="orange">'''Analyse field test results for GPS and CMPS and work on it if required.'''</font>
+*<font color="orange">'''Test the location data from the Geo-controller sensor and Navigation Algorithm. (Lawrence) '''</font>
-*<font color="blue">'''Test the accuracy of check-points from the Blue-tooth controller, location data from the Geo-controller sensor and Navigation Algorithm.'''</font>
+*<font color="black">'''Check overall robustness of the complete system. (Lawrence & Yuming & Tanmay)'''</font>
-*<font color="black">'''Check overall robustness of the complete system.'''</font>
+*<font color="black">'''Establish complete connection on PCB (Lawrence)'''</font>
-*<font color="black">'''Establish complete connection on PCB'''</font>
 *<font color="#808080">'''Update wiki with details.'''</font>
+*<font color="red">'''Midterm: 5/1/2020 -> Online Coding (All Class)  '''</font>
+*<font color="red">'''DEMO Video: 5/5/2020 -> Project Prototype (Lawrence & Yuming) '''</font>
 ||
-*<font color="red">''' Not Started Yet '''</font>
+*<font color="green">'''Complete '''</font>
-*<font color="red">''' Not Started Yet '''</font>
+*<font color="green">'''Complete '''</font>
-*<font color="red">''' Not Started Yet '''</font>
+*<font color="green">'''Complete '''</font>
-*<font color="red">''' Not Started Yet '''</font>
+*<font color="green">'''Complete '''</font>
-*<font color="red">''' Not Started Yet '''</font>
+*<font color="green">'''Complete '''</font>
-*<font color="red">''' Not Started Yet '''</font>
+*<font color="green">'''Complete '''</font>
-*<font color="red">''' Not Started Yet '''</font>
+*<font color="green">'''Complete '''</font>
-*<font color="red">''' Not Started Yet '''</font>
+*<font color="green">'''Complete '''</font>
+*<font color="green">'''Complete '''</font>
 |-
 | '''10''' || '''8 May 2020'''|| '''21 May 2020'''||
-*<font color="black">'''All hands on testing and final bug fixes.'''</font>
+*<font color="black">'''Working on testing and final bug fixes. (Lawrence & Yuming & Naeem)'''</font>
-*<font color="black">'''Check for tuning or calibration of modules if required.'''</font>
+*<font color="black">'''Check for tuning or calibration of modules if required.(Lawrence & Yuming)'''</font>
-*<font color="black">'''Complete end-to-end testing for various scenarios and conditions.'''</font>
+*<font color="black">'''Complete end-to-end testing for various scenarios and conditions. (Lawrence & Yuming)'''</font>
-*<font color="black">'''Create the semester long project activity video and upload to YouTube.'''</font>
+*<font color="black">'''Create the semester long project activity video and upload to YouTube. (Lawrence)'''</font>
-*<font color="#808080">'''Update and finalize wiki.'''</font>
+*<font color="red">'''Individual Evaluation: 5/19/2020 (All Class) '''</font>
+*<font color="red">'''Final: 5/19/2020 -> Online Coding (All Class) '''</font>
+*<font color="red">'''LIVE DEMO: 5/20/2020 -> Final Project (Lawrence & Yuming) '''</font>
 ||
-*<font color="red">''' Not Started Yet '''</font>
+*<font color="green">'''Complete '''</font>
-*<font color="red">''' Not Started Yet '''</font>
+*<font color="green">'''Complete '''</font>
-*<font color="red">''' Not Started Yet '''</font>
+*<font color="green">'''Complete '''</font>
-*<font color="red">''' Not Started Yet '''</font>
+*<font color="green">'''Complete '''</font>
-*<font color="red">''' Not Started Yet '''</font>
+*<font color="green">'''Complete '''</font>
+*<font color="green">'''Complete '''</font>
+*<font color="green">'''Complete '''</font>
 |-
 | '''11''' || '''22 May 2020'''||  ||
-*<font color="red">'''DEMO: Final Project '''</font>
-*<font color="red">'''SUBMISSION: Final Project Wiki'''</font>
+*<font color="red">'''SUBMISSION: 5/22/2020 -> Final Project Wiki (Lawrence & Ellis & Yuming & Tanmay & Naeem & Frank)'''</font>
 ||
-*<font color="red">''' Not Started Yet '''</font>
+*<font color="green">'''Complete '''</font>
-*<font color="red">''' Not Started Yet '''</font>
 |}
@@ Line 325: / Line 332: @@
 |-
 ! scope="row"| 3
-| GPS
+| GPS & Antenna
 | Amazon []
 | 1
-| $ .00 '''per unit including shipping fee'''
+| $ 78.24 ''' including shipping fee'''
 |-
 ! scope="row"| 4
@@ Line 334: / Line 341: @@
 | Amazon []
 | 1
-| $ .00 '''per unit including shipping fee'''
+| $ 41.48 '''including shipping fee'''
 |-
 ! scope="row"| 5
@@ Line 353: / Line 360: @@
 | 1
 | $ 34.23 ''' including shipping fee and tax'''
+|-
+! scope="row"| 8
+| PCB Fabrication
+| JLCPCB
+| 5
+| $ 39.13 ''' including shipping fee and tax'''
+|-
+! scope="row"| 9
+| IR Optocoupler
+| Amazon
+| 5
+| $ 40.01 ''' including one day shipping fee and tax'''
+|-
+|-
+! scope="row"| 10
+| 20x4 LCD Display
+| Adafruit [https://www.adafruit.com/product/198]
+| 5
+| $ 0.00''' (Provided by Naeem Mannan)
 |-
 |}
@@ Line 376: / Line 402: @@
 == CAN Communication ==
-<Talk about your message IDs or communication strategy, such as periodic transmission, MIA management etc.>
+All the controllers on Nimble communicate with each other via CAN(control area network) bus with termination resistors. 120-ohm termination resistors avoid signal reflection. Can is basically a broadcast bus that operates on standard baud rates like 100K, 125K, 250K, 500K, or 1Mbps. It is based on half-duplex communication over a differential pair.
+CAN communication is based on the priority of messages in case of bus arbitration. A lower ID message always has a higher priority. Nimble’s DBC is shown in the next section which is used to generate CAN messages
+To detect modules that are missing in action due to error in reception, MIA is configured. It replaces the data with safe values when the communication cuts off. Below is an example snippet of code that configures CAN MIA for the driver controller which sets default values for data sent from the sensor, geographical, and motor controller. It also configures a mia threshold which is the amount of time that should pass before an MIA should occur and replace the values for its respective module data structure.
+  const uint32_t dbc_mia_threshold_SENSOR_DATA = 10 * 100;
+  const uint32_t dbc_mia_threshold_COMPASS = 10 * 100;
+  const uint32_t dbc_mia_threshold_MOTOR_DATA = 10 * 100;
+  const dbc_SENSOR_DATA_s dbc_mia_replacement_SENSOR_DATA = {};
+  const dbc_COMPASS_s dbc_mia_replacement_COMPASS = {};
+  const dbc_MOTOR_DATA_s dbc_mia_replacement_MOTOR_DATA = {};
 === Hardware Design ===
-<Show your CAN bus hardware design>
-=== DBC File ===
+<table>
-<Gitlab link to your DBC file>
+<tr>
-<You can optionally use an inline image>
+<td>
+[[File:CAN_diagram_nimble.png|575x375px| thumb| left |'''Overall diagram of CAN''']]
+ </td>
+<td>
+<td>
+[[File:CAN_diagram_overall_nimble.jpeg|575x375px| thumb| left |'''Overall diagram of CAN - With other correspondence devices on Controller''']]
+</td>
+</tr>
+</table>
+=== DBC File ===
 Shown below is the DBC implementation for this project.
@@ Line 505: / Line 554: @@
 <BR/>
-== Sensor ECU ==
+=== Busmaster ===
-<Picture>
+To monitor the messages being sent on the CAN-BUS, a PCAN dongle which Preet lent each group was used to connect to the CAN Bus and monitor messages being sent. The software used to monitor and analyze the messages sent on the CAN bus was Busmaster. An image of the busmaster message window and a signal graph is shown below.
+[[File:Busmaster nimble.JPG|thumb|center|900px|'''Busmaster Message Window showing the message received on the PCAN dongle''']]
+[[File:Bus master graph.JPG|thumb|center|900px|'''Busmaster signal graph displaying middle, left, right, and rear sensor message data ''']]
+==  Sensor ECU   ==
 [https://gitlab.com/Project-Nimble/sjtwo-c/-/tree/RC_Infra/BridgeAndSensor_v1.0 Sensor node Gitlab]<br>
@@ Line 516: / Line 572: @@
 We have embedded 4 sensors on Nimble. We have arranged 3 LV-MaxSonar-EZ series Maxbotix ultrasonic sensors in the front section of the car; one at right, one at left and one in the center. The fourth Ultrasonic sensor is placed at the rear end of the car. These sensors provide very short to long-range detection. It provides sonar range information from 6-inches out to 254-inches with 1-inch resolution.
+<table>
+<tr>
+<td>
+[[File:Nimble- sensor and board connection diagram rev.jpg|thumb|450px|left|''' sensor and SJTWO connection description''']]
+</td>
+<td>
+[[File:Pin description of ultra.jpg|thumb|450px|right|''' Pin specification of Ultrasonic sensors ''']]
+</td>
+</tr>
+</table>
-    [[File:Nimble- sensor and board connection diagram rev.jpg]]            [[File:Pin description of ultra.jpg]]
 A maxbotix sensor gives out 3 types of output- analog, RS232, and Pulse width. We have used analog output and hence, utilized on-board analog to digital converters- ADC2 (P0.25), ADC3 (P0.26), ADC4 (P1.30), and ADC5 (P1.31).
@@ Line 562: / Line 626: @@
 === Software Design ===
-The sensor implementation is mostly done in 100HZ function of periodic callbacks. The basic operation objective is to trigger all the sensors whenever (count%5==0) one after another and get the converted minimum distance value from ADC readings every time (count%5 ==4). As we have used Analog output, we used on board ADC and we had to make few changes in the ADC driver. The SJTWO board has 4 ADC but the pin out diagram showed only 3 and misnamed one ADC with DAC (P0.26). So we added P0.26 that is ADC3 channel into the code and modified the ADC driver accordingly. The ADC readings are basically in form of raw voltage and hence are converted to distances in centimetres. To get the most accurate distance value of each sensor, we used buffer that gives out the minimum distance reading. This distance is sent over CAN to driver controller which further processes these distances and coordinates the movement of car accordingly. The flowchart below shows the implementation of our sensor controller.
+The sensor implementation is done in 100Hz callback function, part of the periodic callbacks module. To give an overview, all the sensors are triggered at once and then given a minimum buffer time of 30ms for the outbound signal to bounce back and get detected, thereby giving us the raw distance readings. These readings are then processed inside a buffer to send the minimum value over CAN at '''20Hz'''. As we have used Analog output, we used the available onboard ADCs with a few changes to the ADC driver implemented by Preet. The SJTWO board has 4 ADC pins available, with P0.26, which can be configured as both an ADC and a DAC. So we configured P0.26, that is ADC3 channel into the code and modified the ADC driver accordingly. The ADC readings are in the form of raw voltage and hence are converted to distances in centimetres. To get the most accurate distance value of each sensor, we used a buffer that gives out the minimum distance reading at 20Hz. This distance is sent over CAN to the Driver Node which further processes these distances and triggers the motors accordingly. The flowchart below shows the implementation of our Sensor controller.
-                     [[File:Flowchart.jpg]]
+                     [[File:Flowchart.jpg|thumb|700px|center|'''flowchart of sensor controller's operation ''']]
@@ Line 571: / Line 635: @@
 '''A.  Initialization:'''
-. Initialization of sensors: As we are using on board ADC to get voltage, we first initialize all the ADCs (ADC2, ADC 3, ADC 4, ADC 5). We then configured IOCON registers to set up all the ADC’s.
+. Initialization of sensors: As we are using onboard ADC to get voltage, we first initialize all the ADCs (ADC2, ADC 3, ADC 4, ADC 5). We then configured IOCON registers to set up all the ADCs, according to the LPC40xx datasheet.
 . Initialized Buffer and can.
@@ Line 577: / Line 641: @@
 '''B. Triggering the sensors:'''
-. Configured the SJTWO pin connected to sensor’s RX as GPIO output. This pin will be served as trigger pin to the sensors.
+. Configured available SJTWO GPIO pins, to be connected to the sensor’s RX pin, as GPIO output. These pins will serve as trigger pins to the sensors.
-. The sensors are triggered in 100Hz functions. To do so, trigger pin is set for 30 microseconds and the reset.
+. The sensors are triggered in at 20Hz inside the 100Hz function. To do so, the trigger pin is set for 30ms and the reset.
-. Triggered all the sensors every time (count%5==0) one after other, starting with left, right, middle and lastly rear.
 '''C. Read sensor values:'''
-We are using ADC values to obtain the distance. All the values are in form of analog voltage and represents number of steps in terms of voltage level. To get real voltage value from raw, it is multiplied by adc voltage and divided by voltage scaling defined by voltage level powering the sensors (here 3.3 V) and manufacturing scaling (Vcc/512).
+We are using ADC values to obtain the distance. All the values are in the form of analog voltage and represents the number of steps in terms of voltage level. To get real voltage value from raw, it is multiplied by the ADC voltage and divided by voltage scaling defined by voltage level powering the sensors (here 3.3 V) and manufacturing scaling (Vcc/512).
-The distance values obtained are stored in buffer. All the sensors have individual buffer that collects the distance values and get the minimum of all the values.
+The distance values obtained are stored in the Circular buffer module. All the sensors have an individual buffer that collects the distance values and get the minimum of all the values.
 '''D. CAN transmission:'''
-The lowest distance in cm of all the sensors are sent to driver controller over CAN bus. We have used CAN1 to achieve this task. The driver then coordinates the movement according to the distance value.
+The lowest distance in 'cm' of all the sensors is sent to driver controller over CAN bus. We have used CAN1 to achieve this task. The driver then coordinates the movement according to the distance value.
 === Technical Challenges ===
-< List of problems and their detailed resolutions>
+* '''Issue 1:''' Unreliable reading when the whole RC car is being powered by one single portable battery. IR sensor, which was to mounted as the rear sensor wasn't receiving enough power to work reliably.
+** '''Solution:''' We ended up switching the IR sensor to another ultrasonic sensor, which works even at 3.3V, in order to make the rear readings reliable.
+* '''Issue 2:''' Interference between the sensors was a major issue, wherein an obstacle on the right would make both the Right and Middle sensors to read low values.
+**'''Future work:''' The best possible solution would be print sensor mounts in advance, after deciding upon the sensors to be used. This will ease the process of testing the RC car.
 <HR>
 <BR/>
-== Motor ECU ==
+== '''Motor ECU''' ==
-<Picture of ECU>
+Our Motor Controller node is responsible to control the DC and Servo motor from the RC car, and additional RPM sensor measurement to get the RPM value from each rotation so we can have control to the speed or our RC car.
+The motor controller logic the steering and speed will be calculated within the Driver Node Controller through the CAN bus messages. Then, the Motor Controller node will output the feedback of RPM value for the Driver node to display the RPM value through CAN bus to the Driver module.  The Motor controller node will also use this RPM feedback from the sensor to maintaining the speed making sure that the car is under certain threshold of RPM value,
+so it won't become too fast or too slow. The CAN message function will be constantly called at 10Hz of the periodic callbacks, while the speed check for the RPM value will be call every 500 ms.
 [https://gitlab.com/Project-Nimble/sjtwo-c/-/tree/motor_node Motor node Gitlab]<br>
 === Hardware Design ===
+'''The hardware interface details of MOTOR Module with SJOne board are given above:'''
 <table>
 <tr>
@@ Line 617: / Line 692: @@
 </tr>
 </table>
+<table>
+<tr>
+<td>
 {| class="wikitable"
 |-
@@ Line 647: / Line 727: @@
 | Pin GND
 |}
+ </td>
+<td>
+<td>
+</td>
+</tr>
+</table>
 <HR>
 <BR/>
@@ Line 656: / Line 743: @@
 ====SERVO Motor ====
+The direction of the RC car is dependent on the servo motor, based on various PWM signals of 10% to 20% it will steers the front wheels from right to left direction. The servo motor has 3 wires, where one is the PWM input signals, other two wires responsible to the VCC of 6V and Ground. We powered our Servo motor using the ESC output voltage from the Nickel Metal Hydride (NiMh) battery of the RC car, and the PWM signals will be generated from motor controller of P2.1 of SJtwo Board.
 <table>
 <tr>
@@ Line 662: / Line 752: @@
   </td>
 <td>
+{| class="wikitable"
+|-
+! scope="col"| Label
+! scope="col"| Function
+! scope="col"| PWM_value
+|-
+! scope="row"| 1
+| Left
+| PWM -> 15.1 - 20
+|-
+! scope="row"| 2
+| Middle
+| PWM -> 15
+|-
+! scope="row"| 3
+| Right
+| PWM -> 10 - 14.9
+|}
 <td>
@@ Line 672: / Line 779: @@
 |-
 ! scope="row"| 1
-| VCC from Lipo 7.2V to Servo
+| VCC from NiMh 7.2V to Servo
 | VCC
 |-
 ! scope="row"| 2
-| DC Signal from Servo
+| Servo Signal to SJtwo
 | P2.1
 |-
@@ Line 688: / Line 795: @@
 ====DC Motor ====
+The DC motor is already connected with the ESC as default built-in from the RC car, the purpose of ESC (Electronic Speed Control) is to control the DC motor Using PWM signals from the controller. It also regulated (converted) the 7.4V NiMh battery power sources into stable 6V energy output for the DC motor and servo. The DC motor is similar to the Servo where it takes in 10% to 20% duty cycle of PWM signals to control the RC car Forward, Stop, and Reverse mode. One thing that's interesting is that there is certain sequence for the DC motor to go from Forward state into the Reverse state, based from the design of the ESC it is to protect the DC motor from breaking.
+''' The sequence of the DC motor to go to Reverse is that it have to received the PWM of Reverse duty cycle for two times before it actually starting to go in reverse direction. '''
 <table>
 <tr>
@@ Line 695: / Line 805: @@
 <td>
 [[File:ESC_nimble.png|275x275px| thumb| left |'''ESC''']]
+</td>
+</tr>
+</table>
+<table>
+<tr>
 <td>
 {| class="wikitable"
 |-
@@ Line 703: / Line 822: @@
 |-
 ! scope="row"| 1
-| VCC from Lipo 7.2V to ESC
+| VCC from NiMh 7.2V to ESC
 | VCC
 |-
@@ Line 714: / Line 833: @@
 | Pin GND
 |}
+<td>
+{| class="wikitable"
+|-
+! scope="col"| Label
+! scope="col"| Function
+! scope="col"| PWM_value
+|-
+! scope="row"| 1
+| Left
+| PWM -> 15.1 - 20
+|-
+! scope="row"| 2
+| Straight
+| PWM -> 15
+|-
+! scope="row"| 3
+| Right
+| PWM -> 10 - 14.9
+|}
 </td>
 </tr>
@@ Line 720: / Line 858: @@
 ====RPM Sensor ====
+RPM sensor is the device that calculated the one single rotation per certain duration of time frame. It can be a device that used magnet to calculated one rotation or IR Optocoupler with its corresponding disk, as long as the device can successfully achieve the job of counting one rotation cycle. Our RPM sensor in mounted on the car shaft instead of the built-in RPM sensor from Traxxas, when ever the IR Optocoupler sending the signals to the P2.6 as the interrupts it will increment the rotation_count for the computation on the RPM value. The IR Optocoupler have 4 PIN, where we only used its VCC, GND, and D0 for our RC car, the VCC need power of 3.3V to 5V to properly power-up the device, and the GND should have common GND that connected all the devices, while D0 pin will goes to P2.6 in our Motor Controller.
 <table>
 <tr>
@@ Line 754: / Line 895: @@
 === Software Design ===
-<List the code modules that are being called periodically.>
+The dc motor and servo motor operation is fundamentally based on PWM (Pulse Width Modulation). We set the PWM frequency to 100Hz for both dc and servo motor.<br>
+Pseudo code for initializing PWM to 100Hz. <br>
+  gpio__construct_with_function(2, 0, 1);
+  gpio__construct_with_function(2, 1, 1);
+  '''// gpio input for interrupt'''
+  gpio__construct_as_input(2, 6);
+  '''// gpio initialize the interrput'''
+  gpio2__attach_interrupt(6, GPIO_INTR__RISING_EDGE, pwm_get_speed);
+  lpc_peripheral__enable_interrupt(LPC_PERIPHERAL__GPIO, pwm_get_speed, NULL);
+  pwm1__init_single_edge(frequency_in_hertz); '''// usually use 100 hz'''
+<table>
+<tr>
+<td>
+[[File:DC_motor_flowchart_nimble.png|275x275px| thumb| center |'''DC Motor Flow Chart - State Machine''']]
+ </td>
+<td>
+[[File:Servo_motor_flowchart_nimble.png|400x300px| thumb| center |'''Servo Motor Flow Chart''']]
+<td>
+[[File:RPM_sensor_flowchart_nimble.png|400x300px| thumb| center |'''RPM Flow Chart''']]
+</td>
+</tr>
+</table>
+==== Servo motor Pseudo Code ====
+The servo motor is connected to the Pin 2.1 on SJTwo Board. The servo received the command of -2 to 2 from the can1 of driver node every 10 Hz, where the -2 represents full left and 0 as neutral and 2 as full right turn.
+Then the data from CAN bus of driver node will be process under if statement to select the respective rotation of the servo motor according to the data received from the driver logic. Under is some Pseudo logic of the function,
+once the rotation is finish selected it will use ''motor_control_status__process_data();'' to choose the respective PWM of the Servo, where left would be 20 and right would 10 and 15 as neutral state of the servo motor.
+  if (motor_cmd_data->MOTOR_CMD_STEERING == steer_left) {
+    motor_control_status__process_data(MOTOR_STATUS_LEFT);
+  } else if (motor_cmd_data->MOTOR_CMD_STEERING == steer_right) {
+    motor_control_status__process_data(MOTOR_STATUS_RIGHT);
+  } else if (motor_cmd_data->MOTOR_CMD_STEERING == steer_slight_left) {
+    motor_control_status__process_data(MOTOR_STATUS_SLIGHTLY_LEFT);
+  } else if (motor_cmd_data->MOTOR_CMD_STEERING == steer_slight_right) {
+    motor_control_status__process_data(MOTOR_STATUS_SLIGHTLY_RIGHT);
+  } else if (motor_cmd_data->MOTOR_CMD_STEERING == steer_straight) {
+    motor_control_status__process_data(MOTOR_STATUS_STRAIGHT);
+  }
+==== DC motor Pseudo Code ====
+The DC motor is connected to the Pin 2.0 on SJTwo Board. The DC received the command of PWM every 10 Hz, where the 20 represents full forward and 15 as neutral and 10 as full reverse. Because the value of DC motor when it is
+or 10 would be too fast for the sensor to even react and transfer the signal to the motor node, we reduce the forward and reverse PWM as 15.5 for forward and 14.5 for reverse. The DC motor will be modify under the switch case
+''state machine'' for FORWARD, REVERSE, STOP state of the DC motor. And the RPM sensor will be getting the speed of the RC car to increase or reduce the speed of the RC car in term of PWM. Below is partial code of the FORWARD
+state. The '''pwm_request_by_app''' will receive the speed request of from driver node in CAN1 bus, which will select and make the state change accordingly, and '''pwm_maintain_speed_forward();''' will just be using the PWM sensor in the next section to monitor the rotation of the RC car so it doesn't be come too fast or too slow.
+   if (0 >= pwm_request_by_app) {
+      pwm_DC_motor(motor_speed_stop);
+      pwm_servo_motor(servo_center);
+      motor_value_type = MOTOR_STATUS_STOP;
+      break;
+    }
+    pwm_maintain_speed_forward();
+==== RPM sensor Calculation Pseudo Code ====
+The RPM sensor is connected to the Pin 2.6 on SJTwo Board. It will received the signals from the every time it finish the single rotation. It will use interrupt to register these pulses in a 500ms time frame and then calculate the speed in m/s based on the formula:
+  rotation_per_min = rotation_value * ((60s * 1000hz "1 second")/duration_time) ''//where the duration_time is 500ms.''
+Because there is some difficulty in installing the magnet RPM sensor into the RC car, we end up using the LM393 Speed Detection Sensor Module with the Type IR Optocoupler and it's respective disks for the IR Optocoupler.
+So within one single rotation it will received '''20 rotation_count''', which them we will have to divided the rotation_count we received from the interrupt by 20 to get the actual one rotation from the wheel. The equation will be the following below.
+    rotation_value = rotation_count / 20;
+And ''rotation_count'' will be received using code below.
+  rotation_count = rotation_count + 1;
+  clear_pin_interrupt2(6);
 <HR>
 <BR/>
 === Technical Challenges ===
-< List of problems and their detailed resolutions>
+* '''Issue 1:''' One of the challenges to deal with in this project on the motor node, is probably the incompatibility of the RPM sensor from Traxxas. The RC car we got even thought it is from the Traxxas it doesn't have the slot for us to put in the RPM sensor and the magnet disk.
+** '''Solution:''' We end up just using the IR Optocoupler and the middle car shaft that connect from the rear motor to the front wheel. The whole isn't perfect fit so we do have to make the hole for the disk larger and use glue gun to secure the location of the IR Optocoupler.
+* '''Issue 2:''' Probably not the issue but more of what future work we could done to improve our current motor controller. As we run the DEMO there is overshoot problem when the RC trying to reach the checkpoints, due to not having implementation of PID controller.
+** '''Future work:''' The solution would be increasing the CAN message commands of steering angle that Driver node sent to the motor node, and compute those angles from driver node to make variety of option for servo steering instead of just 5 options: slight left, left , slight right, right, and straight.
+* '''Issue 3:''' Another future work that we could be doing, is that we notice during our demo our RC car will stop for a bit due to going over the threshold of RPM value on the RC car.
+**'''Future work:''' There are two possible solution to this issues, first one is to make the increment and decrement of the maintain_speed function smaller, so it won't over shoot the RPM value generated from the RC car. Another solution is to adjust the RPM value of the threshold, so that it can be easier for the DC motor to main it's PWM.
 <HR>
@@ Line 766: / Line 995: @@
 == Geographical Controller ==
-[https://gitlab.com/Project-Nimble/sjtwo-c/-/tree/RC_infra/GEO_module Geo Module Gitlab]<br>
+[https://gitlab.com/Project-Nimble/sjtwo-c/-/tree/RC_infra/GEO_module Geo Module Gitlab link]<br>
 The geographical controller is responsible for interfacing with a GPS and Compass module in order to receive the current heading(in degrees) and the current destination in the form of GPS coordinates (in degrees, hours, minutes, seconds). It is also responsible for receiving the needed destination coordinates sent by the BRIDGE controller which are needed along with the current GPS location coordinates to calculate the destination heading angle and distance to destination and checkpoints. The current compass heading angle is also sent to the DRIVER controller such that it can be integrated into the driver logic to determine the heading angle to steer and drive towards the destination.
 === Hardware Design ===
+In essence, the Geo-controller is interfaced with a GPS and Compass through UART2 and UART3, respectively. Additionally, the Geo-controller is interfaced with a CAN transceiver in order to receive and send messages from and to other nodes.
 <center>
@@ Line 782: / Line 1,013: @@
 </center>
-=== Hardware Interface ===
+==== Hardware Interface ====
-==== GPS ====
+===== GPS =====
 The GPS is responsible for sending GPS NMEA sentences to the Geographical controller to parse and tokenize in order to get the current latitude and longitude in the units, degrees:hours:minutes:seconds. The sentence desired to extract the coordinates is the GPGGA sentence which contains fixed GPS coordinates. The GPS module that we used for this project was the "Ultimate GPS breakout board" from Adafruit. The module was interfaced with the UART2 port of the SJTwo LPC4078 Controller with a baud rate of 9600 and with 1 stop bit.
@@ Line 789: / Line 1,020: @@
 <tr>
 <td>
-[[File:Ultimate gps breakout board nimble.jpg|thumb|400px|left|]]
+[[File:Ultimate gps breakout board nimble.jpg|thumb|400px|left|'''Ultimate GPS Breakout board from Adafruit''']]
 </td>
 <td>
@@ Line 816: / Line 1,047: @@
 </table>
-==== Compass ====
+===== Compass =====
-The compass is required to get the current heading of the RC car such that it can send the heading information from the geographical controller to the driver controller to perform destination navigation as part of the driver logic. The compass module purchased for this project was the CMPS14 compass module. This module was interfaced to the (Geographical) SJTwo controller using UART3, a baud rate of 9600, and 2-stop bits.
+The compass is required to get the current heading of the RC car such that it can send the heading information from the geographical controller to the driver controller to perform destination navigation as part of the driver logic. The compass module purchased for this project was the CMPS14 compass module. This module was interfaced to the (Geographical) SJTwo controller using UART3, a baud rate of 9600, and 2-stop bits. The compass can be operated in two modes, I2C and serial(UART) mode. The compass utilized for the project was set in serial mode using UART2. Its register contents and various commands include receiving the bearing angle in 16 or 8-bit and altering the calibration settings and profiles. Additionally, the cmps14 is tilt-compensated and includes an accelerometer, gyro-meter, and magnetometer.
 <table>
 <tr>
 <td>
-[[File:Cmps14 pinOut Heading.PNG|thumb|500px|left|]]
+[[File:Cmps14 pinOut Heading.PNG|thumb|500px|left|'''CMPS14 Compass Module''']]
 </td>
 <td>
@@ Line 853: / Line 1,084: @@
 </table>
-=== Software Design ===
+<table>
+<tr>
+<td>
+[[File:CMPS14 registers for serial mode.PNG|thumb|450px|left|'''CMPS14 Registers and Commands for Serial Mode''']]
+</td>
+<td>
+[[File:Compass Calibration.jpg|thumb|400px|'''Compass Calibration flow-chart''']]
+</td>
+</table>
+=== Software Design and Implementation ===
-High-level software flow of the geographical controller
+High-level software flow of the geographical controller and periodic callbacks utilized.
 <center>
@@ Line 871: / Line 1,112: @@
 </table>
 </center>
+==== GPS NMEA sentence parsing and tokenization ====
+GPS run once is called in the 10Hz periodic callback and is essentially done through obtaining a stream of (GPS NMEA sentence) bytes from the GPS module through UART, storing the stream into a line buffer FIFO. The stream of bytes are then popped to a handle line where the stream of bytes or the GPS strings are then handled and processed by checking for the $GPGGA sentence, in particular, using strstr(). If the string "$GPGGA" is found, then tokenization begins using sscanf() for the relevant information required for extraction: latitude, latitude direction, longitude, longitude direction, and the valid fix value. Before the essential information is extracted, a check must be made using the extracted valid GPS fix value. If the valid GPS fix is greater than 0 (1 or 2 are the only possibilities), then it indicates a valid GPS fix versus, otherwise, if the value is 0, then it is an invalid fix, therefore it should not extract the coordinates. If the latitude direction is South("S" or "s"), then the coordinates extracted will be multiplied by -1. Similarly, if the longitude direction is West("W" or "w"), then the extracted longitude is multiplied by -1. Manual calibration is also implemented by(in our case) adding to the latitude and longitude coordinates. This was done because the readings given to us by the GPS were very poor.
+<table>
+<tr>
+<td>
+[[File:GPS parsing.jpg|thumb|400px|'''GPS Parsing software flow-chart''']]
+</td>
+</table>
 ==== Calculating destination bearing angle ====
-Calculating the destination bearing angle between the current and destination longitude and latitude coordinates was done using a formula.
+Calculating the destination bearing angle between the current and destination longitude and latitude coordinates was done using the formula as follows...
-  θ = atan2( sin Δλ ⋅ cos φ2 , cos φ1 ⋅ sin φ2 − sin φ1 ⋅ cos φ2 ⋅ cos Δλ )
+  Formula: θ = atan2( sin Δλ ⋅ cos φ2 , cos φ1 ⋅ sin φ2 − sin φ1 ⋅ cos φ2 ⋅ cos Δλ )
+  where...
    θ  = destination bearing angle
    φ1 = Latitude of origin coordinate
@@ Line 892: / Line 1,145: @@
    c = 2 ⋅ atan2( √a, √(1−a) )
    d = R ⋅ c
+  where...
+  R = earth's radius = 6,371,000 meters
+  d = distance between current and destination gps coordinates
+  c = angular distance in radians
+  a = is the square of half the chord length between the points.
+==== Testing Area and GPS Navigation Checkpoint algorithm ====
+The test are we chose was in a small intersection in a suburban neighborhood. The checkpoints set were set in a manner that would demonstrate that the RC car can navigate through the intersection without cutting through corners through sidewalks as a real would do so. The Longitude and Latitude coordinates were taken from google maps and used to insert into a static const struct array. The algorithm must iterate through the array of checkpoints and determine which point would be navigated towards next based on how close the point is to the car and at the same time how close the point is to the destination.
+<table>
+<tr>
+<td>
+[[File:Checkpoints plan b.PNG|thumb|500px|left|'''Checkpoints set on google maps''']]
+</td>
+<td>
+[[File:Checkpoint algo.jpg|thumb|300px|right|''' Checkpoint software design flow-chart''']]
+</td>
+</table>
 === Technical Challenges ===
@@ Line 903: / Line 1,176: @@
 * '''Issue 3:''' The checkpoints set using google maps for our area used for testing were shifted when doing physical testing with the RC car. This was due to the poor accuracy of the GPS despite our efforts in performing some manual calibration of the GPS.
 **'''Solution:''' The solution, although not perfect, was to set an offset to the original checkpoints such that the newly shifted coordinates would reflect the checkpoints originally set using google maps.
+* ''' Issue 4: ''' Another issue encountered was the failure of connecting to the mobile application in time of the demo.
+** ''' Solution:''' The only solution we had was to hardcode GPS coordinates for the destination instead.
 <HR>
@@ Line 910: / Line 1,186: @@
 <BR/>
-== Communication Bridge Controller & LCD ==
+== Communication Bridge Controller ==
-<Picture and link to Gitlab>
+[https://gitlab.com/Project-Nimble/sjtwo-c/-/tree/RC_Infra/BridgeAndSensor_v1.0 Bridge controller GitLab link]
+'''note:''' The bridge and sensor controller are separate in the report to provide clarity of the modules used in each node. In reality, the bridge and sensor nodes are implemented together in one SJTWO controller.
+The bridge controller is responsible for receiving and sending data from and to the mobile application of this project. For this project, the bridge and sensor nodes are controlled by one SJTWO microcontroller.There are several ways to make affective communication between SJTWO and mobile application such as Zigbee, WIFI and Bluetooth. Nimble bases its communication with mobile app through HC-05 bluetooth module. The bridge controller is interfaced with a bluetooth module in order to connect to the mobile application. Its main purpose is to receive GPS destination coordinates set by the user of the mobile app and send the destination to the geographical controller to be processed and determine a destination heading for the RC car to navigate to. In addition, the bridge controller may receive debug information such as sensor, compass, motor rpm, and current GPS coordinates to be sent and displayed on the mobile app.
 === Hardware Design ===
+The HC-05 modules are very clever pieces of hardware, as they translate incoming Bluetooth communication to serial data. So once configured this gives the tinkerer the possibility to achieve serial communication over Bluetooth.
-=== Software Design ===
+<table>
-<List the code modules that are being called periodically.>
+<tr>
+<td>
+[[File:Bluetooth pin description.jpg|thumb|450px|left|''' HC-05 pin description''']]
+</td>
+<td>
+[[File:Bluetooth pin diagram.jpg|thumb|700px|right|''' Interfacing Bluetooth with SJTWO board''']]
+</td>
+</tr>
+</table>
+The HC-05 acts transparently, meaning that you just communicate with the serial port it is connected to and the module then sends/receives via Bluetooth. A typical operating voltage of hc-05 is between 4-6V and has nominal range of 100m. The communication was uart based and operates at 115200 baud rate.The ultrasonic sensors and bridge resides on the same controller board. The pin connection description of the module is shown in the figure below. The TX and RX end are connected to P2.48 and P2.49 of SJTWO board which is RX3 and TX3. The same controller also houses 4 sensors and the the communication takes place via can transceiver.  Can1 is used to transmit the values to other modules that can further act upon data.
+=== Software Design and Implementation ===
+The software for this part was a Bluetooth module for the SJ2 board. The data sent from the mobile application will be parsed and sent to the geographical controller using the dbc encode and send method. Additionally, sensor, compass, and motor messages would be decoded to be received from their respective controllers. This data would then be parsed by python in the main app to send to the(mobile app) front end.
+<center>
+<table>
+<tr>
+<td>
+[[File:Bridge Controller Software Flow (1).jpg|thumb|450px|left|''' Bridge controller software flow-chart''']]
+</td>
+<td>
+[[File:Bridge Controller Periodic 1Hz.jpg|thumb|500px|center|''' Bridge controller periodic callback 1Hz flow-chart''']]
+</td>
+<td>
+[[File:Bridge Controller Periodic 10Hz.jpg|thumb|450px|right|''' Bridge controller periodic callback 10Hz flow-chart]]
+</td>
+</tr>
+</table>
+</center>
+==== Bluetooth run once ====
+The software design is similar to the GPS run once in terms of absorbing data from UART and adding the bytes to a line buffer. The differences lie in tokenizing the gps_line that is being sent from the mobile app. The data being sent is the GPS latitude and longitude itself which is delimited by a " : ". We can parse the latitude and longitude as well as the directions easily by iterating through the gps line by the length of the coordinates and storing the respective coordinates by checking whether the delimiter, ":" has been detected or not.
+<center>
+<table>
+<tr>
+<td>
+[[File:Bluetooth receive.jpg|thumb|450px|center|''' Bluetooth receive software flow-chart''']]
+</td>
+</tr>
+</table>
+</center>
+==== Bluetooth send ====
+Sending data to the HC-05 module is done by using the uart__put() method provided in the sjtwo-c development environment from Preet.
+<center>
+<table>
+<tr>
+<td>
+[[File:Bluetooth send.jpg|thumb|450px|center|''' Bridge controller software flow-chart''']]
+</td>
+</tr>
+</table>
+</center>
 === Technical Challenges ===
-< List of problems and their detailed resolutions>
+* ''' Issue 1: ''' Bluetooth module - the main problem with this was trying to get the parts to print on Hercules after sending data from the App.
+** ''' Solution: ''' This issue was resolved once the stop bits were figured out.
-<HR>
+* ''' Issue 2: ''' Data formation - a problem with this was getting the correct way to send data to the Python back end and then parsing the information.
-<BR/>
+** ''' Solution: '''This was resolved by making the data sent in a certain way.
-== Driver Module ==
+== Driver Controller & LCD ==
+[https://gitlab.com/Project-Nimble/sjtwo-c/-/tree/RC_infra/driver/motor Driver Module Gitlab link]
-<Picture and link to Gitlab>
+The driver controller is responsible for performing driver logic which will execute both obstacle avoidance and destination navigation. Additionally, an LCD display screen is used as a dashboard to provide the user with meaningful information such as sensor values, GPS destination set, compass bearing degree, distance to the destination, and speed information of the car.
+<table>
+<tr>
+<td>
+[[File:LCD display car.JPG|450px|thumb|center|'''LCD Display located at the rear of the car''']]
+</td>
+<td>
+[[File:LCD display close.JPG|450px|thumb|center|'''Close-up of LCD display showing sensor, current heading degree ,destination heading degree, distance, and speed information''']]
+</td>
+</tr>
+</table>
 === Hardware Design ===
-=== Software Design ===
+The only hardware that the driver is required to be interfaced with, is the LCD display. The LCD display used for this project is a 20x4 LCD screen and is interfaced using I2C with the aid of an I2C backpack which came with the display.
-<List the code modules that are being called periodically.>
+<table>
+<tr>
+<td>
+[[File:Driver Controler Hardware Design (1).jpg|450px|thumb|center|'''Driver Controller Hardware Design''']]</td>
+</tr>
+</table>
+==== Hardware Interfacing ====
+===== LCD =====
+<table>
+<tr>
+<td>
+[[File:LCD screen front.jpg|thumb|450px|left|'''20x4 LCD Display''']]
+</td>
+<td>
+{| class="wikitable" style="text-align: center; width: 400px; height: 200px;"
+|+ SJTWO and LCD Display Interfacing
+|-
+! No.
+! SJTwo Controller Pin
+! LCD I2C backpack Pin
+! Function
+|-
+! 1
+| VCC-5V Power Bank|| Vin || Power pin for LCD
+|-
+! 2
+| SDA-P0.10 || SDA || SDA pin
+|-
+! 3
+| SCL-P0.11 || SCL || SCL pin
+|-
+! 4
+| Ground Port|| GND || Ground pin
+|}
+</td>
+</tr>
+</table>
+=== Software Design and Implementation===
+<center>
+<table>
+<tr>
+<td>
+[[File:Driver Controller software flow (1).jpg|425px|left|thumb|'''Driver controller software flowchart''']]
+</td>
+<td>
+[[File:Driver periodic callback 1Hz.jpg|400px|left|thumb|'''Driver Periodic callback 1Hz software flow chart''']]
+</td>
+</tr>
+</table>
+</center>
+<center>
+<table>
+<tr>
+<td>
+[[File:Driver Periodic callback 10Hz.jpg|400px|thumb|center|'''Driver Periodic 10Hz software flow chart''']]</td>
+<td>
+[[File:Driver periodic callback 20Hz.jpg|400px|thumb|right|'''Driver Periodic 20Hz software flow chart''']]
+</td>
+</tr>
+</table>
+</center>
+==== Driver Logic ====
+===== Obstacle Avoidance =====
+Obstacle avoidance is implemented first by setting a comfortable detection threshold range(in cm) for the sensors. These threshold values determine whether an action must be taken if a sensor detects an object equal to or less than the allowed threshold. For example, if the left sensor detects an object that is closer than or equal to a threshold of 30 cm, and if the right and middle sensor do not, then the RC car should steer right to avoid the detected object on the left. If no object is detected by the front three sensors, then the car should resume GPS navigation. When an action is determined, the driver controller sends motor commands(through CAN) to the motor controller to update the speed and/or steering of the RC car.
+The code snippet below shows object avoidance for far front objects or when the front sensor does not detect any objects nearby, so the left and right sensor values are compared against each other to determine whether a slight left or slight right turn should be taken when avoiding an object on the left or right.
+  static void driver_logic__get_motor_commands_for_far_away_front_object(void) {
+  if ((driver_SENSOR_SONAR.SENSOR_SONARS_right <= sensor_threshold_mid) &&
+      (driver_SENSOR_SONAR.SENSOR_SONARS_left > sensor_threshold_mid)) {
+    driver__update_motor_cmd(MOTOR_STEER_CMD_slight_left, MOTOR_SPEED_CMD_forward);
+  } else if ((driver_SENSOR_SONAR.SENSOR_SONARS_left <= sensor_threshold_mid) &&
+             (driver_SENSOR_SONAR.SENSOR_SONARS_right > sensor_threshold_mid)) {
+    driver__update_motor_cmd(MOTOR_STEER_CMD_slight_right, MOTOR_SPEED_CMD_forward);
+                                        .
+                                        .
+[[File:Driver Logic.jpg|thumb|center|700px|''' Driver Logic software flow-chart''']]
+=====Destination Navigation =====
+The navigation logic implemented within the driver logic of the driver controller is responsible for having the RC car steer towards the destination. This is done by updating the motor steering commands to turn in the direction such that the current heading of the RC car matches the destination bearing angle that is calculated and sent from the geographical controller. Additionally, the navigation logic should be implemented in such a way that it does not interfere with the obstacle avoidance such that avoiding obstacles on the way to the destination is still the highest priority. Lastly, a complimentary angle to the current heading angle is calculated to help determine whether it is better to steer right or left when comparing the current and destination heading angles.
+<center>
+<table>
+<tr>
+<td>
+[[File:Compass navigation.jpg|425px|left|thumb|'''GPS Navigation logic example''']]
+</td>
+<td>
+[[File:Navigation Logic.jpg|700px|left|thumb|'''GPS Navigation driver logic software flow chart''']]
+</td>
+</tr>
+</table>
+</center>
+The code snippet below shows a partial implementation of the GPS navigation in the driver logic. First, if the car is within 3 meters of the destination, then the car will stop as it has arrived at its destination. If not, it will then go on to check the cases when the current heading angle is equal to the destination angle and if so, it should continue straight towards the destination. The inner if() check statements check whether if the current heading is greater than or equal to 180 degrees. If so, it will then compare the current and complimentary heading with the destination heading angle and either turn slight left or slight right if the right conditions are met.
+  if (distance_to_destination <= 3.0) {
+    driver__update_motor_cmd(MOTOR_STEER_CMD_straight, MOTOR_SPEED_CMD_stop);
+  } else {
+    if (current_heading == destination_bearing) {
+      driver__update_motor_cmd(MOTOR_STEER_CMD_straight, MOTOR_SPEED_CMD_forward);
+    } else if (current_heading >= 180) {
+      if (destination_bearing > current_heading || destination_bearing < current_heading_compliment) {
+        driver__update_motor_cmd(MOTOR_STEER_CMD_slight_right, MOTOR_SPEED_CMD_forward);
+      } else if (destination_bearing < current_heading || destination_bearing > current_heading_compliment) {
+        driver__update_motor_cmd(MOTOR_STEER_CMD_slight_left, MOTOR_SPEED_CMD_forward);
+      }
+                                               .
+                                               .
+==== LCD Display ====
+The LCD display for this project displays sensor values, compass heading data, distance to destination, destination bearing angle, and the RPM value. The first and second row of the LCD contains the sensor values, the middle(M), rear(Rr), left(L), and right(R) sensors. The third row displays the compass(CMP)heading and the distance to destination in meters(m). Lastly, the fourth row contains the destination bearing angle(BRG) and the revolutions per minute(RPM) value of the car motor speed.
+<table>
+<tr>
+<td>
+[[File:LCD display close.JPG|450px|thumb|center|'''LCD debug information: Middle(M) Rear(Rr) Left(L) Right(R) sensor values, Compass heading(CMP), Distance-to-destination(m), Destination-bearing-angle(BRG), and RPM motor value(RPM)''']]
+</td>
+</tr>
+</table>
+=====Initialization=====
+The LCD is first reset to clear the screen of contents on startup of the RC car and then initialized to begin updating information on the display. The LCD is initialized by sending a series of commands before writing characters to the display. Commands to enable interfacing mode to 4-bit mode is done first. The display is then cleared and the cursor is set to autoincrement such that when a character is written to the LCD, the cursor will automatically increment to the next space for the next character to be written. Lastly, the LCD will start at the first row(LINE 1). Additionally, a delay must be added for the commands to successfully be sent to the LCD.
+  void LCD__init(void) {
+  LCD__command_to_LCD(FOUR_BIT_MODE);
+  LCD__command_to_LCD(DISPLAY_AND_CURSOR);
+  LCD__command_to_LCD(CLEAR_SCREEN);
+  LCD__command_to_LCD(AUTOINCREMENT_CURSOR);
+  LCD__command_to_LCD(LINE1);
+  delay__ms(5);
+  }
+===== Updating the LCD Status =====
+Updating the status of the display was called in the 1Hz periodic callback. The function takes the struct values of each debug information and is put into a buffer to be written onto the LCD display. Before writing each debugging information, for example, the middle and left sensor values, a command must be sent to indicate the row in which the values should be written. This is done for all pieces of debug information.
+<table>
+<tr>
+<td>
+  void LCD_status__display_on_screen(void) {
+  char lcd_buffer[20];
+  LCD__command_to_LCD(CLEAR_SCREEN);
+  LCD__command_to_LCD(LINE1);
+  sprintf(lcd_buffer, "M: %i", lcd_sensor.SENSOR_SONARS_mid);
+  LCD__string_to_LCD(lcd_buffer);
+  LCD__command_to_LCD(LINE1 + 10);
+  sprintf(lcd_buffer, "L: %i", lcd_sensor.SENSOR_SONARS_left);
+  LCD__string_to_LCD(lcd_buffer);
+  LCD__command_to_LCD(LINE 2 );
+  sprintf(lcd_buffer, "Rr: %i", lcd_sensor.SENSOR_IR_rear);
+  LCD__string_to_LCD(lcd_buffer);
+  LCD__command_to_LCD(LINE 2 + 10);
+  sprintf(lcd_buffer, "R: %i", lcd_sensor.SENSOR_SONARS_right);
+  LCD__string_to_LCD(lcd_buffer);
+                .
+                .
+                .
+</td>
+<td>
+[[File:LCD status update.jpg|thumb|'''LCD status update software flow-chart ''']]
+</td>
+</tr>
+</table>
 === Technical Challenges ===
-< List of problems and their detailed resolutions>
+*'''Issue 1:''' The first issue with the driver controller was testing obstacle avoidance in a physical test with the RC car. This issue was mostly trial and error when trying to set well-balanced sensor thresholds.
+** ''' Solution: ''' Trial-and-error in doing physical tests to see how the RC car reacts and to determine what sensor value threshold would be adequate enough to detect objects far enough such that the RC car has enough time to react.
+*''' Issue 2: ''' Another issue that we faced was updating the LCD display. Since the commands that are required to be sent to the LCD require some delays, updating the LCD in a periodic call in the 10Hz or above would end up resetting the micro-controller.
+** ''' Solution: ''' Putting the LCD display update function was put into the 1Hz periodic callback.
+*''' Issue 3: ''' Fitting all information on the LCD display was difficult considering the size limit of the 20x4 LCD.
+**''' Solution: ''' Applying short but meaningful abbreviations to the labels of each debug information onto the display. A better solution would be is to print multiple status screens for different forms of information.
 <HR>
@@ Line 941: / Line 1,489: @@
 == Mobile Application ==
-<Picture and link to Gitlab>
-https://gitlab.com/Project-Nimble/sjtwo-c/-/tree/react-app is the branch that has the main workings of the React-app development.
+[[File:App.PNG|thumb|400px|]]
-=== Hardware Design ===
+[https://gitlab.com/Project-Nimble/sjtwo-c/-/tree/react-app '''Mobile App Gitlab link''']
 === Software Design ===
-<List the code modules that are being called periodically.>
+The software's main front end code was written in Javascript while the backend was written in Python flask to send and receive data from the microcontroller to the app. The methods of sending GPS coordinates from the app to the microcontroller was using a location's address or a point and click map from google. To receive the data from the microcontroller, the data had to be sent from the Bluetooth module in a specific way such that python could parse through the data and then separate it into sensor and sensor value. The sent data would be picked up every five seconds so that this would allow for the user to send data without having sockets closing from the code before the data could send.
-The software's main front end code was written in Javascript while the backend was written in Python flask to send and receive data from the micro controller to the app. The methods of sending GPS coordinates from the the app to the microcontroller was using a location's address or a point and click map from google. To receive the data from the microcontroller, the data had to be sent from the bluetooth module in a specific way such that python could parse through the data and then separate it into sensor and sensor value. The sent data would be picked up every five seconds so that the this would allow for the user to send data without having sockets closing from the code before the data could send.
+[[File:App diagram.PNG|thumb|500px|center|]]
 === Technical Challenges ===
-The main technical challenge was learning Javascript without having any prior experience in coding Javascript, but to do this lots of research was done on how to make classes, send data to the backend, and how to make the webpage dynamic in updating information. Another challenge was making the bluetooth module work with the microcontroller for this class. The difficulties in this was that the bluetooth module was made for an arduino so the settings had to be modified so that it could work with other microcontrollers by modifying the Baud rate and stop bits. The last technical challenge was working with a python backend. The reason for this is that there is a method that was needed to get information from the front end that was not familiar to the normal python, instead GET and POST methods had to be researched to get the data and then printed on the webpage instead of using a simple print function.
+The main technical challenge was learning Javascript without having any prior experience in coding Javascript, but to do this lots of research was done on how to make classes, send data to the backend, and how to make the webpage dynamic in updating information. Another challenge was making the Bluetooth module work with the microcontroller for this class. The difficulties in this were that the Bluetooth module was made for an Arduino so the settings had to be modified so that it could work with other microcontrollers by modifying the Baud rate and stop bits. The last technical challenge was working with a python backend. The reason for this is that there is a method that was needed to get information from the front end that was not familiar to the normal python, instead of GET and POST methods had to be researched to get the data and then printed on the webpage instead of using a simple print function.
-< List of problems and their detailed resolutions>
-Javascript and React-framework : The challenge in this was learning a new language, but to resolve this many youtube videos were watched and forums were read to learn how to program in a new language.
-Bluetooth module development : This was difficult because the stop bits had to be played around with until the right one was selected, but after changing the values around the proper setup was made after a while
-Flask and python backend : The problems with this was programming in an unconventional python way, instead it dealt with POST and GET methods to gather front end data and if there were errors then the simple print functions couldn't be used to find the values of variables but they had to be printed onto a second webpage. To fix this, many tries were taken to try and get the data from front end as well as finding a way to find the data values easier.
+Javascript and React-framework: The challenge in this was learning a new language, but to resolve this many youtube videos were watched and forums were read to learn how to program in a new language.<BR/>
+Bluetooth module development: This was difficult because the stop bits had to be played around with until the right one was selected, but after changing the values around the proper setup was made after a while<BR/>
+Flask and python backend: The problems with this were programming in an unconventional python way, instead, it dealt with POST and GET methods to gather front end data and if there were errors then the simple print functions couldn't be used to find the values of variables but they had to be printed onto a second webpage. To fix this, many tries were taken to try and get the data from the front end as well as finding a way to find the data values easier. <BR/>
-<BR/>
-<HR>
 <HR>
 <BR/>
 == Conclusion ==
-<Organized summary of the project>
-<What did you learn?>
+Nimble was a great opportunity to learn test-driven design strategies, which helped lower the amount of time troubleshooting issues. It also taught us much about using Git for version control. The project also gave us experience working with embedded systems technologies such as the following:
-Nimble was a great opportunity to learn test-driven design strategies, which helped lower the amount of time troubleshooting issues. It also taught us much about using Git for version control. The project also gave us experience working with embedded systems technologies such as CAN bus communications, DBC files, GPIO, and signal debugging with BusMaster.
+* '''Can Bus''' (Including Bus Master):
+** Using the CAN bus to communicate with multiple different devices instead of using SPI and UART, which is something totally new.
+** How to debug and understand the CAN message using the BusMaster.
+** Modifying the DBC to get different CAN messages, and data that transfer in-between different controller nodes.
+* '''Sensor''':
+** How to properly initialize the sensor and transfer the creating the driver logic-based from the data of the sensor.
+* '''GPS & Compass''':
+** NMEA data packets and what to expect for the GPS module. It is also interesting on how to initialize and calibrate the compass and GPS
+* '''Unit Testing''':
+** We learned the Unity and CMOCK framework, and how to unit-test our code modules which sped up the development of the components of the project. In particular, the GPS and Compass were thought to be the hardest to get working, but with an early start and unit-testing, these modules faced little issues to get working. The only difficulties as mentioned before was the calibration and accuracy.
+** We believe that this is by far the most useful and interesting experience that we have encountered this semester. Although we're still not experts on writing flawless unit-tests, it doesn't change the fact of how incredibly revolutionary and useful it was during our project.
+* '''GIT''':
+** We learned all the basic go GIT and it helps us collaborate on the different modules virtually without physical meeting. (Because of Corona Virus)
+Although there were some problems encountered while doing this project, we were able to finish the majority of the basic tasks required of the project. Unfortunately, we were not able to implement the mobile application as a requirement due to some issues encountered with the connectivity of the Bluetooth module which occurred in the last week of the project. Additionally, because of the COVID-19 outbreak, classes had to be conducted through google hangouts for the rest of the semester. The outbreak also made it difficult to meet physically with teammates which made it difficult to not only integrate and test the RC car, but it also reduced involvement in the project of every teammate. Despite these shortcomings of the project, the overall experience was fun and interesting. The class and project helped us learn a TON of new concepts and skills that will prove valuable in the future and industry.
 === Project Video ===
+[https://www.youtube.com/watch?v=HXQysrMhCF4&feature=youtu.be Team Nimble RC Car video link]
 === Project Source Code ===
-Gitlab Project Link - [https://gitlab.com/...]
+[https://gitlab.com/Project-Nimble/sjtwo-c/-/tree/master Project Nimble Gitlab link]
 <BR/>
 === Advice for Future Students ===
-<Bullet points and discussion>
+* '''Advice 1:''' Always make sure the teammate you choose is responsible since '''teammate is the most important part of this group project'''. If any teammate is not responsible, make sure you pursue them and keep track of their progress. Otherwise, you will end up finishing their lack of progress. Also, make sure you get your teammates' contact information, besides slack, like phone or text messages.
+* '''Advice 2: ''' ''' Set an earlier deadline ''' and make sure your teammates finish before the deadline. ''' There should be no tolerance ''' because this project will be more difficult when there is a lack of contribution from team members. If there are no strong leaders within your team, the result of your project will not be great. Also, assign important tasks, like GPS and Mobile application, to someone with the most knowledge and reliability, since those two are by far the most difficult part of the RC car. A rough draft of the ''' mobile application should be highly considered early on. Especially if nobody in your team has experience in mobile app development. ''' It is HIGHLY recommended to refer to the previous semesters' team to get a ''' GOOD LOOK ''' of ''' Preet's expectations '''.
+* '''Advice 3:''' Make sure the GPS modules you purchase is over $90 where it is more reliable. '''DO NOT''' purchase the GPS our team purchase, where has is shown significant failure. '''Make sure you guys spend more money on the GPS module as it is a critical component of the project.'''
+* '''Advice 4:''' Plan a backup in case something goes wrong. Always make sure you give enough time to polish your final Project. This includes having enough time to make a good enclosure or packaging for the RC car. Additionally, it's good to adapt to a change of situation if needed. In our case, due to the COVID-19 outbreak, group meetings were scheduled over google hangout instead of in-person.
+* '''Advice 5:''' '''Overall this is an interesting class project, where you learn a lot. Please take advantage of this project by asking Preet lots of questions. Again, the teammates you choose will be important. ''DO NOT'' wait until the second lecture to form your team. Make sure you form your team during the first two weeks of the lecture! '''
+* '''Advice 6:''' Make sure everyone in your group shows up in the Preet's Lectures because Preet provided a lot of useful information related to our major and project. Missing one day of lectures can cause 1 week of set back for your project.
+* '''Advice 7:''' Make sure to read through previous reports before finalizing on the sensors to be used. Buy a few additional sensors as a backup. Make sure you solder the pins with keeping their eventual placement on the RC car in mind. Desoldering the pins on the ultrasonics is a really tedious job, so save yourself some time.
 === Acknowledgement ===
+* Preet for introducing us to new concepts/technical skills and continuing to teach us innovative practices that would not be taught in the industry.
+* ISAs Aakash Chitroda and Vignesh Kumar for being great ISAs in guiding and keeping us on track throughout the semester!
+* Previous 243 groups who provided great wiki reports of their projects and have given us advice and tips which helped us with our project.
 === References ===
-The website used to calculate destination distance(haversine formula) and the destination heading angle:
+* website used to calculate destination distance(haversine formula) and the destination heading angle:[https://www.movable-type.co.uk/scripts/latlong.html bearing angle and distance link]
-[https://www.movable-type.co.uk/scripts/latlong.html]
+* Latitude and Longitude Finder [https://www.latlong.net/ lat and long finder]
+* google maps for setting checkpoints [https://www.google.com/maps google maps]

Difference between revisions of "S20: Nimble"

Latest revision as of 04:45, 23 May 2020

Contents

Nimble Autonomous RC Car

Abstract

Introduction

Team Members & Responsibilities

Team Deliverables Schedule

Parts List & Cost

Printed Circuit Board

Design and Architecture

Fabrication

Challenges

CAN Communication

Hardware Design

DBC File

Busmaster

Sensor ECU

Hardware Design

Hardware Interface

Software Design

Technical Challenges

Motor ECU

Hardware Design

Hardware Interface

SERVO Motor

DC Motor

RPM Sensor

Software Design

Servo motor Pseudo Code

DC motor Pseudo Code

RPM sensor Calculation Pseudo Code

Technical Challenges

Geographical Controller

Hardware Design

Hardware Interface

GPS

Compass

Software Design and Implementation

GPS NMEA sentence parsing and tokenization

Calculating destination bearing angle

Calculating destination distance

Testing Area and GPS Navigation Checkpoint algorithm

Technical Challenges

Communication Bridge Controller

Hardware Design

Software Design and Implementation

Bluetooth run once

Bluetooth send

Technical Challenges

Driver Controller & LCD

Hardware Design

Hardware Interfacing

LCD

Software Design and Implementation

Driver Logic

Obstacle Avoidance

Destination Navigation

LCD Display

Initialization

Updating the LCD Status

Technical Challenges

Mobile Application

Software Design

Technical Challenges

Conclusion

Project Video

Project Source Code

Advice for Future Students

Acknowledgement

References

Navigation menu

Search