This Arduino Car is used for the Master's thesis of David (@Code-Schwabe). It has the capabilities to
- drive autonomously following a line on the ground
- measure the distance in 2 directions (front and right rear)
- communicate with another Arduino Car using WiFi
The hardware in use is the following:
- 1 Arduino Mega 2560 Rev3
- 1 Arduino Nano Rev3
- 1 chassis with 4 simple DC motors
- 1 motor controller L298N
- 1 WiFi shield ESP8266-01S
- 3 infrared sensors KY-033
- 2 ultrasonic distance sensors HC-SR04 (tdb)
- ...many cables, glue and a breadboard
The hardware is wired as depicted here:
The two Arduinos communicate via an I2C bus connection.
It can be powered by any 12V power source - for mobility reasons, a 3 cell LiPo battery is used in our current set-up. It is also useful to connect the battery to a switch first, so the car isn't powered up directly on battery connection.
For some simple examples with the hardware device above, refer to the Sensor Playground.
The software in this repository has two purposes:
- Demonstrate the capabilities of the Arduino Car.
- Provide device libararies (where possible) for the car's capabilities (continuous components) that can later be included in the code generation process.
The CarCoordinator encapsulates the communication with other cars for coordinated behavior. Currently, it connects to an MQTT broker where it listens to "START" and "STOP" messages. Upon receiving a message, it instructs the LineFollower component to start or stop the car accordingly.
The CarCoodrinatorLib serves to test the I2C and MQTT libraries that were created for the MUML-based code generation. Currently, the MQTT library is not working properly. Messages are only consume occasionally, i.e., the callback is not always called when a new message arrives for the subscribed topic. Sometimes it works, sometimes it doesn't - the problem's cause could not be found yet.
Therefore, in order to demonstrate the workings of the custom I2C library separately, the I2cLibTester and I2cLineFollower are created. They can be deployed to the Arduino car: The I2cLibTester will send messages to START and STOP the car in random periods, and the I2cLineFollower will adapt its driving behavior depending on these messages while following a line on the ground.
The I2cLibTester demonstrates the workings of the I2cCustomLib.
Extends the functionality of the LineFollowerLib with listening to messsages from I2C, demonstrating the workings of the I2cCustomLib. It essentially implements the LineFollower by using the I2cCustomLibrary and the LineFollower-Libraries from LineFollowerLib.
The LineFollower implements the interaction with the sensors (infrared, distance) and actuators (dc motors via motor controller) in order to make the car drive autonomously while following a black line on the ground and measure the distance to other cars or obstacles. The LineFollower module also listens to I2C messages that tell the car to "START" or to "STOP".
The LineFollowerLib contains the functionality of the LineFollower module and abstracts it into libraries that allow easier reuse. At the moment, the I2C functionality is not included.
The following pictures show an exemplary set-up where the wiring is a little more visible (might be helpful for reconstruction).
And without the battery:
And the following pictures show an exemplary set-up where the wiring is a little more hidden (looks better ✨).
