S19: Lightfury - Revision history

Proj user3: /* Project Video */

2019-05-24T01:05:40Z

‎Project Video

Proj user2: /* Motor ECU */

2019-05-24T01:02:48Z

‎Motor ECU

Proj user2: /* Motor ECU */

2019-05-24T01:02:38Z

‎Motor ECU

Proj user2 at 01:01, 24 May 2019

2019-05-24T01:01:52Z

Proj user2 at 00:58, 24 May 2019

2019-05-24T00:58:06Z

Show changes

Proj user2: /* Master Module */

2019-05-24T00:56:27Z

‎Master Module

Proj user2: /* Hardware Design */

2019-05-24T00:55:51Z

‎Hardware Design

Proj user2: /* References Used */

2019-05-24T00:47:24Z

‎References Used

Proj user2: /* Hardware Design */

2019-05-24T00:45:28Z

‎Hardware Design

Proj user2: /* Parts List & Cost */

2019-05-24T00:45:09Z

‎Parts List & Cost

← Older revision		Revision as of 01:05, 24 May 2019
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	=== Project Video ===		=== Project Video ===
		+
		+	https://youtu.be/-F9lSJ-Cud8

	=== Project Source Code ===		=== Project Source Code ===

@@ Line 580: / Line 580: @@
 * RPM Sensor (Hall Effect Sensor)
 * LCD Module
 [[File:CMPE_243_S19_MotorECU_Block.png|800px|thumb|center| '''Block Diagram of Motor ECU''']]

← Older revision		Revision as of 01:02, 24 May 2019
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	[[File:CMPE_243_S19_MotorECU_Block.png\|800px\|thumb\|center\| '''Block Diagram of Motor ECU''']]		[[File:CMPE_243_S19_MotorECU_Block.png\|800px\|thumb\|center\| '''Block Diagram of Motor ECU''']]

−	~~<font color = RED> '''TODO Niraj: Update the diag to add LCD and CAN'''. </font>~~

	=== Prerequisites ===		=== Prerequisites ===

← Older revision		Revision as of 01:01, 24 May 2019
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	</pre>		</pre>
		+
		+	== System Architecture ==
		+
		+	[[File:CMPE 243 S19 LF Sys Arch.jpeg\|center\|800px\|'''PCB Schematic]]
		+
	== Printed Circuit Board ==		== Printed Circuit Board ==

@@ Line 741: / Line 741: @@
 === Software Design ===
 The master controller gets start-stop command from bridge controller. This signal is sent from the mobile application by the user. From each ultrasonic sensors, it gets distance to obstacle and compares it to threshold value. The master sees the following conditions with respect to obstacles from the three ultrasonic sensor: left, front and right.
 {| class="wikitable"
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 The '1' represents obstacle detected and '0' represents no obstacle. This is based on the thresholds determined through trials and error method. The threshold is distance after which the object is to be avoided. The sensor can sense upto 125 inch in front of it and has 2 inch blind spot right in front of it. Threshold selection has to be such that, the turns would be able to avoid obstacle without crashing into it and some delay to transmit the motor command and then motor latency respond to the master controller command. It was observed that with higher speed higher threshold are required to cater for motor controller latency. Also the threshold for front sensor is higher than the adjacent left and right sensor because of the position and bending radius of car. The car reduces speed on turning at corners or around edges as well to avoid collision. There are 2 levels of turning possible on each side of the car. It is dependent on the size of the obstacle observed by combination of the sensor. When front and any adjacent signal detects '1', the object to be avoided is assumed to be thicker or wide (wall or corner) and needs to be turned away by a larger angle. For people travelling into the cars peripherally the car turns by smaller angle or 'soft_steers'. When object is detected by all 3 sensors we assume it has run into a corner or dead end and needs to be reversed. This is possible by reversing the motor direction in left to get out of that spot and then navigating to the destination.
-Next it checks for direction and magnitude from geo sensor input to send motor controller commands for driving and steer control. The geo sensors sends direction for turning towards destination and magnitude for turning angle. This turning angle is then converted to 'soft_steer' and 'mod_steer' based on angle thresholds. Upon reaching the destination location the geo sensor sends stop signal to Master Controller. The Master Controller than issues motor stop command to the Motor Controller. Thus the geo signal helps Master with navigation to destination.
+Next it checks for direction and magnitude from geo sensor input to send motor controller commands for driving and steer control. The geo sensors sends direction for turning towards destination and magnitude for turning angle. The magnitude indicates the turning curve while the direction tells the master to turn left or right. This turning angle is then converted to 'soft_steer' and 'mod_steer' based on angle thresholds. For example: If turning angle is greater than 30 it would be 'soft_steer' and greater than 60 would be 'mod_steer'. This is useful for doing reverse. The magnitude of the angle given by the geo controller is greater than 60, hence the master controller keeps issuing steering command till the car heading matches to the destination bearing. Also with turning at the corner as per checkpoint use similar conditions. The geo controller keeps issuing higher magnitude to the motor till the bearing and heading dosent match. As both bearing and heading overlap it has negligible magnitude . On this the motor continues in this direction unless it gets another input from the ultrasonic sensor controller.  Upon reaching the destination location the geo sensor sends stop signal to Master Controller. The Master Controller than issues motor stop command to the Motor Controller. Thus the geo signal helps Master with navigation to destination and stopping upon reaching the destination.
-Also the master controller monitors and displays heartbeat for remaining controllers through on board LED. If any board resets, the CAN message received is MIA and onboard LED for that controller goes off.
+Also the master controller monitors and displays heartbeat for remaining controllers through on board LED. If any board resets, the CAN message received is MIA and onboard LED for that controller goes off. This is critical to the functioning of the algorithm as all the controller should be functioning for the car to navigate. If any controller resets or fails it can result in disruption of autonomous navigation of the car.
 === Technical Challenges ===

← Older revision		Revision as of 00:55, 24 May 2019
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	[[File:CMPE 243 S19 LF motor HW2.png\|800px\|thumb\|center\| '''Hardware Design Motor ECU''']]		[[File:CMPE 243 S19 LF motor HW2.png\|800px\|thumb\|center\| '''Hardware Design Motor ECU''']]
		+
		+	==== RPM Sensor ====

	=== Software Design ===		=== Software Design ===

← Older revision		Revision as of 00:47, 24 May 2019
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	*[https://traxxas.com/sites/default/files/Slash%204x4%20RPM.pdf RPM sensor 6520 Installation Guide]		*[https://traxxas.com/sites/default/files/Slash%204x4%20RPM.pdf RPM sensor 6520 Installation Guide]
	*[https://traxxas.com/support/Programming-Your-Traxxas-Electronic-Speed-Control Traxxas Guide for Configuration of Electronics Speed Control]		*[https://traxxas.com/support/Programming-Your-Traxxas-Electronic-Speed-Control Traxxas Guide for Configuration of Electronics Speed Control]
		+	*[https://developer.android.com/guide/topics/connectivity/bluetooth Bluetooth API Android]
		+	*[https://developers.google.com/maps/documentation/android-sdk/start Getting started with maps]

@@ Line 523: / Line 523: @@
 The traxxas chassis came with ECU and servo controller. It has DC motor with servo control for turning. Working on 3.4 V/ 3000mAH power specifications it has axle to rotate all the four wheels. The feedback for PWM controlled speed attained is fed back through magnetic encoder. The front wheels have servo connection for turning. The chassis is placed on suspension unit for shock absorbing. An acrylic sheet is mounted over certain height on which the PCB and controller is placed. The motor controller PWM sends signals for DC motor and servo motor angles for driving the car.
-[[File:CMPE 243 S19 LF motor HW.png|800px|thumb|center| '''Hardware Design Motor ECU''']]
+[[File:CMPE 243 S19 LF motor HW2.png|800px|thumb|center| '''Hardware Design Motor ECU''']]
 === Software Design ===

@@ Line 300: / Line 300: @@
 |-
 ! scope="row"| 8
 | PCB
 |[https://www.pcbway.com/ PCBWay]
@@ Line 305: / Line 311: @@
 | $30.00
 |-
-! scope="row"| 9
+! scope="row"| 10
 | SJOne board
+|