F17: Tata Nano - Revision history

Proj user3: /* Team Members & Responsibilities */

2018-01-18T15:58:31Z

‎Team Members & Responsibilities

Proj user3: /* Testing & Technical Challenges */

2017-12-24T08:33:29Z

‎Testing & Technical Challenges

Proj user3: /* Problem 3 */

2017-12-24T08:28:11Z

‎Problem 3

Proj user3: /* Technical Challenges */

2017-12-24T08:08:18Z

‎Technical Challenges

Proj user3: /* Team Management */

2017-12-24T06:47:51Z

‎Team Management

Proj user3: /* Project Video */

2017-12-23T19:44:19Z

‎Project Video

Proj user12: /* Software Design */

2017-12-23T07:35:47Z

‎Software Design

Proj user12: /* CAN protocol's DBC Design */

2017-12-23T07:34:18Z

‎CAN protocol's DBC Design

Proj user12: /* DBC File */

2017-12-23T07:27:45Z

‎DBC File

Proj user12: /* CAN Bus design */

2017-12-23T07:25:18Z

‎CAN Bus design

@@ Line 69: / Line 69: @@
 ** [https://www.linkedin.com/in/shivam-chauhan-a1ab2ba3/ Shivam Chauhan]
 *  <font color="blue">Motor and I/O Controller</font>
-** Venkat Raja Iyer
+** [https://www.linkedin.com/in/venkat-raja-iyer-a0588550/ Venkat Raja Iyer]
 ** [https://www.linkedin.com/in/mehtajmanan/ Manan Mehta]
 *  <font color="orange">Sensor Controller</font>

@@ Line 1,474: / Line 1,474: @@
 * As the resolution (number of zones/lanes) provided by LIDAR sensor was high, the master code had more cases to handle. e.g. the sonar sensor has 3 zones in front while the LIDAR was programmed to give 9 lanes in front of which we used 5 lanes for navigation.
-== Testing & Technical Challenges ==
+== Testing & Technical Challenges - Overall System ==
 === Testing ===
 ==== Software Testing - Unit Tests ====

@@ Line 1,585: / Line 1,585: @@
 ==== Problem 3 ====
-A timing issue faced in this project was a delay in controllers reacting to CAN messages or a . For example, there existed a delay in the response of the vehicle to stop command sent from the Android app. Upon debugging it was noticed that CAN buffers of the Master controller was full and was taking a while to
+We faced a an issue where the commands sent by the android phone either reached late to the master or was completely dropped or missed. On debugging, we found out that the CAN RX/TX buffer size for the master initially was 10 and we were sending more than 15 messages over CAN at 10Hz and reading CAN at 10Hz. This caused the buffer become full and few messages were dropped. We tried to increase the CAN RX/TX buffer size but as we had bypass filter for CAN messages, all the messages on CAN bus (~18) entered the buffer and in 10Hz periodic task to read those messages, the master had to de-queue each and every message. This caused significant delay in reaction of the car to STOP/START signal from android.
-−
 '''Solution:'''
-Create a try-catch technique to check for successful initialization, otherwise, reattempt initialization.
+* We reduced the number of CAN messages (9) and increased the CAN RX/TX buffer size to 20 such that we get right balance between fast reaction (of master to messages sent on CAN) and no dropping of messages.
 == Conclusion ==

@@ Line 1,571: / Line 1,571: @@
 === Technical Challenges ===
 ==== Problem 1 ====
-Power was a continues problem as more modules keep adding to the system throughout the life of the project.
+Power was a major problem during the project as the LIDAR required a larger current to initialize as compared to when it was running and as more features were added to the system, a single power supply wasn't sufficient. The project also used the powerboost 1000c with a rechargeable Li-Po battery from Adafruit that performed better than 7805 but had a limitation of 1A per module.
 '''Solution:'''
-Used separate supply for LIDAR and GPS to meet current requirements.
+Used separate supply for LIDAR and GPS to meet current requirements and ensure proper initialization of system
 ==== Problem 2 ====
-Compass Calibration was tedious and frequently required calibration that took a lot of time on the field.
+LIDAR sensor is heavily dependent on ambient light and if the sun rays are in line with the LIDAR's optical sensor, the lidar could read stray values and cause the system to report an obstacle although there isn't one
 '''Solution:'''
-Automated the process by using the buttons on the SJOne board. So, if you press button 1, the compass goes into calibration mode and if you press button 2 it completed calibration.
+Still working on the solution but there are better LIDAR sensors in the market that might be expensive but are more impervious to the sunlight as compared to the one used in this project.
 ==== Problem 3 ====
-Lidar initialization fails sometimes, especially when power source is shared.
+A timing issue faced in this project was a delay in controllers reacting to CAN messages or a . For example, there existed a delay in the response of the vehicle to stop command sent from the Android app. Upon debugging it was noticed that CAN buffers of the Master controller was full and was taking a while to
 '''Solution:'''

@@ Line 84: / Line 84: @@
 *Scheduling weekly webcast meetings using Zoom (provided for free by SJSU to its students) on Sundays to share an update of each module.
 *Maintaining a [https://taiga.io/ Tiaga board] to document each person's responsibility for the particular sprint
-*Google Drive to share important files such as datasheets, videos, research links and DBC file between team members
+*Maintaining a Google Drive to share important files such as datasheets, videos, research links between team members

@@ Line 1,596: / Line 1,596: @@
 === Project Video ===
-*  [https://youtu.be/LR__GdiyHEU Demo Video]
+*  [https://youtu.be/imzmpYmaIn8 Demo Video]
 === Project Source Code ===

← Older revision		Revision as of 07:35, 23 December 2017
Line 612:		Line 612:
	=== Software Design ===		=== Software Design ===

		+	The design process of the two sensors is as follows:

	==== Ultrasound Sensor ====		==== Ultrasound Sensor ====

@@ Line 361: / Line 361: @@
 == CAN protocol's DBC Design ==
-Link to the DBC file which defines the CAN communication of the system
+DBC is a format that enables less hassles while developing code to either interpret data received or send data over the CAN bus. This project used DBC effectively.
 [https://gitlab.com/shivam5594/Autonomous-car/blob/embedded/common_dbc/243.dbc DBC link on GitLab]

@@ Line 359: / Line 359: @@
 |}
-== DBC File ==
+== CAN protocol's DBC Design ==
 Link to the DBC file which defines the CAN communication of the system
@@ Line 468: / Line 468: @@
   VAL_ 120 HEARTBEAT_cmd 2 "HEARTBEAT_cmd_REBOOT" 1 "HEARTBEAT_cmd_SYNC" 0 "HEARTBEAT_cmd_NOOP" ;
 </pre>
 == Sensor Controller ==