rosbot

A ROS Python package for my rosbot - running on a Raspberry Pi.

Please note: this code is still in the middle of the development process!

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Step 1: Setup Raspberry with Ubuntu

• Install Ubuntu Desktop (Instruction).

Download and install pigpio

https://abyz.me.uk/rpi/pigpio/download.html (See detailed instructions there - will be installed to /usr/local/lib and /usr/local/bin)

clone this repository

https://github.com/markusk/rosbot

git clone https://github.com/markusk/rosbot.git
cd rosbot

Step 2: Setting up pigpiod for autostart with systemd

sudo cp raspi/etc__systemd__system__rosbot-boot.service /etc/systemd/system/
sudo systemctl daemon-reload
sudo systemctl enable rosbot-boot.service
sudo systemctl start rosbot-boot.service

Step 3: Joystick/Gamepad OS support

sudo apt-get install joystick

Microsoft XBOX Wireless Controller

• Supported by the Kernel - if used with the USB connector.

Gamepad/Joystick test

• Connect a Gamepad to the Pi, start the following command and press any buttons or move some axes:

jstest --normal /dev/input/js0

Step 3: ROS 2

• Install ROS on your Raspberry Pi (Instruction):

• Install ROS packages (+++ TO BE DEFINED !!! +++):

• Do not forget to "autostart" ros; i.e. in your terminal, when logging in:

echo 'source /opt/ros/jazzy/setup.bash' >> ~/.bashrc

Step 5: Create a central place for this repository

• Create your own development directory "develop"

mkdir ~/develop
cd ~/develop

• Clone this repository

git clone https://github.com/markusk/rvr.git

• Create a colcon workspace (ROS 2) with 'src' subfolder:

mkdir -p ~/ros2_ws/src

• Create symbolic link with the name of each ros package from this repository, pointing into the 'src' folder from your ROS/colcon workspace (ros_ws):

cd ~/ros2_ws/src
ln -s ~/develop/rosbot/ROS/colcon_workspace/src/rosbot rosbot
ln -s ~/develop/rosbot/ROS/colcon_workspace/src/testbot testbot

• Now also source your ROS workspace you created:

echo 'source ~/ros2_ws/install/setup.bash' >> ~/.bashrc

• Build the ROS rosbot package

cd ~/ros2_ws
colcon build --symlink-install
source install/setup.bash

Step 4: Build and run ROS 2

Install ROS 2 Jazzy and the Raspberry Pi dependencies using the official ROS 2 Raspberry Pi guide. The active ROS 2 package is ROS/colcon_workspace/src/rosbot; ROS/rosbot.old__TMP!__migrating_to_ros2_! is a non-buildable ROS 1 archive and its launch files must not be used with ROS 2.

From the repository root:

source /opt/ros/jazzy/setup.bash
cd ROS/colcon_workspace
rosdep install --from-paths src --ignore-src -r -y
colcon build --symlink-install --packages-select rosbot
source install/setup.bash

On the Raspberry Pi, install/start pigpio before launching hardware nodes:

sudo apt-get install pigpio python3-pigpio
sudo systemctl enable --now pigpiod
ros2 launch rosbot rosbot_launch.py

The joystick is optional and disabled by default. On the Pi with a controller attached, use:

ros2 launch rosbot rosbot_launch.py joystick_enabled:=true joy_device_id:=0

The launch setup checks that the hostname is exactly rosbot before starting the Linux joystick device node. Motor and LED GPIO access is also enabled only on that hostname; on a Mac, the hardware nodes simulate/no-op. To exercise joystick mapping without a device, publish sensor_msgs/Joy to /joy; to exercise the motor command interface, publish geometry_msgs/Twist to /cmd_vel.

For package details, migrated functionality, parameters, and hardware limitations, see ROS/colcon_workspace/src/rosbot/README.md. The ROS 1 roslaunch, catkin_ws, and ROS_MASTER_URI instructions formerly in this README are obsolete and are not supported by the active package.