Arduino Remote Car

This Project is still under development.

Currently, the chassis does not provide any stability beyond simple mobility.

Furthermore, only 1-way communication from the computer to the car is possible.

The repository itself is the code base for the Arduino Car controlled remotely through ROS.

Parts Needed

• 2x Arduino Uno
• Lots of Wires (preferably with different colors, at least red and black)
• WRL-10532/WRL-10534 Radio Receiver/Transmitter Pair
• 1x Motor H-Bridge IC (I used L293D)
• 1x 5V Voltage Regulator (I used LM78M05C)
• 1x 9V Battery
• 2x DC Motors (I used This just because they were available. The chassis is adapted to this model.)
• 1x small caster wheel (see CAD for dimensions)
• 2x bigger wheels (see CAD for dimensions)
• 1x half-size breadboard
• 2x antenna (I just used solid wires)
• Some zip ties if you want to provide cheap securing to your assembly

Building the Chassis

Get the CAD from here.

The bulk of the chassis can be 3d printed.

In my case, I could not find a good caster wheel, so I 3d printed the wheel and mounted it with sheet metal.

As for the main wheel, I recommend buying them. The dimensions are specified in the CAD file.

Wiring the components

Receiver

The receiver is connected to the arduino.

Transmittor

The transmitter should be connected to your computer.

Software

1. Install rosserial.

   Via Package Manager:

   sudo apt-get install ros-${ROS_DISTRO}-rosserial ros-${ROS_DISTRO}-rosserial-python ros-${ROS_DISTRO}-rosserial-arduino
   

   Alternatively, clone the github repository and run catkin_make.

   cd ~/catkin_ws/src
   git clone git@github.com:ros-drivers/rosserial.git   
   cd ..
   catkin_make
   

2. Build the ros package to remotely control the arduino from your computer.

   export CATKIN_WORKSPACE=${HOME}/catkin_ws #REPLACE WITH YOUR OWN
   git clone git@github.com:yycho0108/ArduinoRemoteCar.git
   cp ArduinoRemoteCar/arduino_rc_car ${CATKIN_WORKSPACE}/src
   cd ${CATKIN_WORKSPACE}
   catkin_make --pkg arduino_rc_car
   

3. Build rosserial_arduino.

   export ARDUINO_LIB_DIR=${HOME}/sketchbook/libraries
   cd ${ARDUINO_LIB_DIR}
   rm -rf ros_lib
   rosrun rosserial_arduino make_libraries.py 
   

   If this fails, check your arduino library directory.

   It may simply be ${HOME}/Arduino/libraries.

4. Install the arduino library VirtualWire to facilitate RF communication.

   Here are Instructions on how to install an Arduino Library.

   Alternatively, simply run the following script:

   export ARDUINO_LIB_DIR=${HOME}/sketchbook/libraries
   wget http://www.airspayce.com/mikem/arduino/VirtualWire/VirtualWire-1.27.zip
   unzip VirtualWire-1.27.zip
   mv VirtualWire ${ARDUINO_LIB_DIR}/VirtualWire
   

Running the code

1. Upload the code to receiver/transmitter arduinos.

   If you encounter an error that you cannot open the serial port, run:

   sudo usermod -a -G dialout <username>
   sudo chmod a+rw /dev/ttyACM0
   

2. Power up the car(connect the battery).
3. Connect the transmitter arduino to your computer via serial port.

4. Check the ports to which the transmitter is connected.

   ls /dev/ttyACM*
   

5. (Optional) To configure permission to access input devices without sudo permission,

   echo 'SUBSYSTEM=="input", MODE="660", GROUP="plugdev"' | sudo tee /etc/udev/rules.d/99-input.rules
   sudo usermod -a -G plugdev $(whoami)
   

6. Launch the ros control node.

   If you haven’t configured access permission to input devices:

   sudo -s
   

   Otherwise, you don’t need to become root.

   To launch the control node:

   roslaunch arduino_rc_car control.launch port:=/dev/ttyACM0
   

7. Press the arrows to control the car remotely.