ROS 2 based robot learning platform.

Click the image to video showing robot design and navigation in action

The BOM has not been designed for easy replication but most all used components and alternatives considered are there with respective links of where were they purchased so maybe it helps someone putting together a similar build :)

Click the image to open BOM

Disclaimer

The following documentation is various commands and information that I've written over the time the robot was in development and everything is not up to date or relevant but maybe it helps someone.

• Add user to usb serial and input groups
  • sudo usermod -a -G input ubuntu
  • sudo usermod -a -G dialout ubuntu
  • sudo usermod -a -G tty ubuntu
• Build rosbot (on both the robot and the remote PC)
  • cd ~/rosbot/ros to open workspace
  • rosdep install -i --from-path src --rosdistro foxy -y to install dependencies
  • git pull && colcon build to pull changes and build workspace
• Launch rosbot on the robot
  • First build it if there have been any changes
  • Open new terminal
  • cd ~/rosbot/ros to open workspace
  • . install/local_setup.bash to load workspace overlay (on both robot and remote pc)
  • ros2 launch odrive_bringup rosbot.launch.py to launch rosbot (run on robot)
  • ros2 launch odrive_bringup rviz.launch.py to launch rviz (run on remote pc)
• Run joystick teleop
  • Open new terminal
  • . install/local_setup.bash to load workspace overlay
  • ros2 launch teleop_twist_joy teleop.launch.py joy_config:='rosbot_xbox_bluetooth' cmd_vel:=/diff_drive_controller/cmd_vel_unstamped to launch joystick teleop
  • Hold down left trigger (button 6) and use left and right joysticks to control speed and rotation
  • Hold down right trigger (button 7) for boost (faster movements)
• Launch odrive manual control (for testing only)
  • Open new terminal
  • . install/local_setup.bash to load workspace overlay
  • ros2 launch odrive_bringup odrive.launch.py to launch odrive test ()
  • ros2 topic pub -r 100 /left_wheel_joint_velocity_controller/commands std_msgs/Float64MultiArray "data: [1]"
  • ros2 topic pub -r 100 /right_wheel_joint_velocity_controller/commands std_msgs/Float64MultiArray "data: [-1]"
  • ros2 launch teleop_twist_joy teleop.launch.py joy_config:='rosbot_xbox_bluetooth' cmd_vel:=/diff_drive_controller/cmd_vel_unstamped to launch joystick teleop
  • Hold down left trigger (button 6) and use left and right joysticks to control speed and rotation
• Launch usb xbox joystick teleop that publishes to /cmd_vel
  • ros2 launch teleop_twist_joy teleop.launch.py cmd_vel:=cmd_vel joy_config:=rosbot_xbox_usb

• Debugging
• ros2 topic echo /joint_states to show joint states including velocity etc
• ros2 topic echo /dynamic_joint_states to show dynamic joint states including axis error etc
• ros2 run tf2_tools view_frames.py to generate frames.pdf frame tree
• rqt to open RQT, add plugins such as Topics > Topic Monitor
• ros2 run xacro xacro ./src/rosbot_description/urdf/rosbot.urdf.xacro to debug what's wrong with URDF file
• ros2 run tf2_ros tf2_echo odom base_link to verify transforms from odom to base_link
  • At time 1634580767.596875940
    • Translation: [6.986, -2.328, 0.000]
    • Rotation: in Quaternion [0.000, 0.000, -0.210, 0.978]
  • At time 1634580768.594622939
    • Translation: [7.108, -2.383, 0.000]
    • Rotation: in Quaternion [0.000, 0.000, -0.213, 0.977]

• https://index.ros.org/p/teleop_twist_joy/github-ros2-teleop_twist_joy/
• https://github.com/ros2/teleop_twist_joy/tree/foxy/
• http://wiki.ros.org/joy
• https://github.com/medusalix/xow need xow to use xbox bluetooth controller
• Configure XOW to use xbox controller over bluetooth
  • sudo apt install cabextract to install dependencies
  • git clone https://github.com/medusalix/xow
  • cd xow
  • make BUILD=RELEASE
  • sudo make install
  • sudo systemctl enable xow
  • sudo systemctl start xow
  • sudo systemctl kill -s SIGUSR1 xow to enable XOW pairing mode (generally not needed)
• Disable ERTM
  • sudoedit /sys/module/bluetooth/parameters/disable_ertm
  • replace N with Y
  • reboot
• Restart bluetooth
  • sudo service bluetooth restart
  • sudo rmmod btusb
• Test controller
  • jstest /dev/input/js0
• Also disable ERTM permanently
  • https://www.addictivetips.com/ubuntu-linux-tips/xbox-one-controllers-over-bluetooth-linux/
  • sudo apt install dkms git linux-headers-uname -r``
  • git clone https://github.com/atar-axis/xpadneo.git
  • cd xpadneo
  • sudo ./install.sh
  • reboot
• Disable internal bluetooth when using dongle
  • sudoedit /boot/firmware/usrcfg.txt
  • add line dtoverlay=disable-bluetooth
  • reboot
  • check with hciconfig -a and hcitool dev
  • does not seem to actually work..
• Connect to bluetooth xbox controller using terminal (on robot)
  • https://simpleit.rocks/linux/shell/connect-to-bluetooth-from-cli/
  • https://raspberrypi.stackexchange.com/questions/114586/rpi-4b-bluetooth-unavailable-on-ubuntu-20-04
  • https://www.makeuseof.com/manage-bluetooth-linux-with-bluetoothctl/
  • sudo apt install bluez pi-bluetooth joystick
  • Append "include btcfg.txt" to sudoedit /boot/firmware/usrcfg.txt
  • reboot
  • hciconfig -a or hcitool dev (from bluez) to check for bluetooth devices
  • bluetoothctl to run interactive bluetooth controller
  • scan on
  • wait for xbox controller (make it pair by holding the pair button, starts to blink rapidly)
  • trust XX:XX:XX:XX:XX:XX to trust the controller
  • connect XX:XX:XX:XX:XX:XX to connect to the controller
  • sudo chmod a+rw /dev/input/js0 to give everyone read-write permissions to joystick
  • sudo chmod a+rw /dev/input/event4 to give everyone read-write permissions to joystick (sometimes it's one of eventX)
• If the joystick /dev/input/eventX does not have correct permissions then (this does not seem to actually work)
  • sudo apt install input-utils to install lsinput tool
  • sudo lsinput to get list of inputs, note the vendor and product of "Xbox Wireless Controller"
  • sudoedit 80-xbox-controller.rules
  • add KERNEL=="event*", ATTRS{idProduct}=="02e0", ATTRS{idVendor}=="045e", MODE="0666" etc that mathes vendor and product
• Test joystick from terminal
  • sudo apt install joystick
  • jstest /dev/input/js0
  • ros2 run joy joy_enumerate_devices
• Test joystick visually
  • sudo apt install jstest-gtk
  • jstest-gtk
• Test joystick messages
  • ros2 topic echo /joy
  • ros2 topic echo /cmd_vel
  • ros2 topic echo /diff_drive_controller/cmd_vel_unstamped

• sudo apt install ros-foxy-gazebo-ros-pkgs

• https://askubuntu.com/questions/1254376/enable-uart-communication-on-pi4-ubuntu-20-04
• Create boot configuration backups
  • cd /boot/firmware
  • sudo cp usrcfg.txt usrconfig.backup.txt
  • sudo cp cmdline.txt cmdline.backup.txt
• Disable console UART
  • add enable_uart=0 to /boot/firmware/usrcfg.txt
  • remove console=serial0,115200 from /boot/firmware/cmdline.txt
• Disable the Serial Service which used the miniUART
  • sudo systemctl stop [email protected]
  • sudo systemctl disable [email protected]
  • sudo systemctl mask [email protected]
• UART Pins
  • Pin 8 TXD GPIO14
  • Pin 10 RXD GPIO15

• https://navigation.ros.org/getting_started/index.html
• Install dependencies
  • sudo apt install ros-foxy-navigation2 ros-foxy-nav2-bringup ros-foxy-cartographer ros-foxy-cartographer-ros ros-foxy-robot-localization ros-foxy-slam-toolbox ros-foxy-gazebo-ros-pkgs ros-foxy-xacro ros-foxy-slam-toolbox
  • sudo apt install ros-foxy-turtlebot3* for testing on remote pc only
• Slam toolbox on the robot
  • Use snap slam-toolbox
  • It has optimizations in it that make it about 10x faster
• Run mapping and navigation
  • ros2 launch slam_toolbox online_async_launch.py to launch slam toolbox mapper
  • ros2 launch nav2_bringup navigation_launch.py to run navigation2

• Clone and build https://github.com/ros-planning/navigation2_tutorials.git
• launch robot ros2 launch sam_bot_description display.launch.py
• Launch usbteleop
  • Open new terminal
  • cd ~/rosbot/ros
  • . install/local_setup.bash
  • ros2 launch teleop_twist_joy teleop.launch.py cmd_vel:=/demo/cmd_vel joy_config:=rosbot_xbox_usb
  • or without the /demo in modified version
• Launch slam_toolbox
  • Open new terminal
  • ros2 launch slam_toolbox online_async_launch.py

• Install Arduino IDE
• Add https://www.adafruit.com/package_adafruit_index.json to Arduino preferences additional boards URLs
• Install board Adafruit nRF52
• Install pip3 install --user adafruit-nrfutil
• Update bootloader
  • https://learn.adafruit.com/introducing-the-adafruit-nrf52840-feather/update-bootloader
  • Double press reset to enter DFU mode
• Install Micro-XRCE-DDS Agent
  • git clone https://github.com/eProsima/Micro-XRCE-DDS-Agent.git
  • cd Micro-XRCE-DDS-Agent && git checkout foxy
  • mkdir build && cd build
  • source /opt/ros/dashing/setup.bash # to share libraries with ros2
  • cmake ..
  • make
  • sudo make install
  • sudo ldconfig /usr/local/lib/

• cmake --version
• sudo apt update
• sudo apt install -y software-properties-common lsb-release
• wget -O - https://apt.kitware.com/keys/kitware-archive-latest.asc 2>/dev/null | gpg --dearmor - | sudo tee /etc/apt/trusted.gpg.d/kitware.gpg >/dev/null
• sudo apt-add-repository "deb https://apt.kitware.com/ubuntu/ $(lsb_release -cs) main"
• sudo apt update
• sudo apt install kitware-archive-keyring
• sudo rm /etc/apt/trusted.gpg.d/kitware.gpg
• sudo apt update
• sudo apt install cmake
• cmake --version

• https://github.com/micro-ROS/micro_ros_mbed
• pip3 install catkin_pkg lark-parser empy colcon-common-extensions mbed-tools
• sudo apt install gcc-arm-none-eabi
• clone repo and cd into it
• mbed-tools deploy
• mbed-tools compile -m LPC1768 -t GCC_ARM -f

Installation guide.

• Enable universe (probably not needed)
  • sudo apt install software-properties-common
  • sudo add-apt-repository universe
• Add repository
  • sudo apt update && sudo apt install curl gnupg2 lsb-release
  • sudo curl -sSL https://raw.githubusercontent.com/ros/rosdistro/master/ros.key -o /usr/share/keyrings/ros-archive-keyring.gpg
• Add repository to sources list
  • echo "deb [arch=$(dpkg --print-architecture) signed-by=/usr/share/keyrings/ros-archive-keyring.gpg] http://packages.ros.org/ros2/ubuntu $(lsb_release -cs) main" | sudo tee /etc/apt/sources.list.d/ros2.list > /dev/null
• Install ROS
  • sudo apt update
  • sudo apt install ros-foxy-desktop
• Install autocomplete
  • sudo apt install -y python3-argcomplete
• Add sourcing ROS to bashrc
  • echo "source /opt/ros/foxy/setup.bash" >> ~/.bashrc
• Add colcom_cd to bashrc
  • echo "source /usr/share/colcon_cd/function/colcon_cd.sh" >> ~/.bashrc
  • echo "export _colcon_cd_root=~/ros2_install" >> ~/.bashrc
• Check environment variables
  • printenv | grep -i ROS
• Set domain id (random number between 0-101 inclusive)
  • echo "export ROS_DOMAIN_ID=<your_domain_id>" >> ~/.bashrc
• Test ROS (open in separate terminals)
  • ros2 run demo_nodes_cpp talker
  • ros2 run demo_nodes_py listener
• Install ros bag for data recording/playback
  • sudo apt-get install ros-galactic-ros2bag ros-galactic-rosbag2-storage-default-plugins

• Install VSCode
  • sudo snap install --classic code

• Install
  • sudo apt install ros-foxy-turtlesim
• Check the package installed
  • ros2 pkg executables turtlesim
• Start turtlesim
  • ros2 run turtlesim turtlesim_node
• Start teleop to control the turtle
  • ros2 run turtlesim turtle_teleop_key

• Install rqt
  • sudo apt update
  • sudo apt install ~nros-foxy-rqt*
• Run rqt
  • rqt
• Add service called
  • select Plugins > Services > Service Caller
  • Call /spawn with x=1.0, y=1.0, name='turtle2'
• Remap control to turtle 2
  • ros2 run turtlesim turtle_teleop_key --ros-args --remap turtle1/cmd_vel:=turtle2/cmd_vel
• Render rtq graph
  • rqt_graph
  • can also add to rtq by Plugins > Introspection > Nodes Graph

• Run node
  • ros2 run turtlesim turtlesim_node
  • ros2 run turtlesim turtle_teleop_key
  • ros2 run turtlesim turtlesim_node --ros-args --log-level WARN to run with custom log level
• List resources
  • ros2 node list
  • ros2 topic list
  • ros2 topic list -t to also show message types
  • ros2 service list
  • ros2 service list -t to also show service types
  • ros2 action list
  • ros2 param list
• Get node info
  • ros2 node info /my_turtle
• Show data published to topic
  • ros2 topic echo /turtle1/cmd_vel to see velocity commands
  • ros2 topic echo /turtle1/pose to see changing pose
• Get topic info
  • ros2 topic info /turtle1/cmd_vel
• Show messsage interface
  • ros2 interface show geometry_msgs/msg/Twist
• Publish message to topic
  • ros2 topic pub <topic_name> <msg_type> '<args>' where args is in YAML syntax
  • ros2 topic pub --once /turtle1/cmd_vel geometry_msgs/msg/Twist "{linear: {x: 2.0, y: 0.0, z: 0.0}, angular: {x: 0.0, y: 0.0, z: 1.8}}" publishes once
  • ros2 topic pub --rate 1 /turtle1/cmd_vel geometry_msgs/msg/Twist "{linear: {x: 2.0, y: 0.0, z: 0.0}, angular: {x: 0.0, y: 0.0, z: 1.8}}" publishes continuosly at 1Hz
• Show how often data is published to a topic
  • ros2 topic hz /turtle1/pose
• Get service type info
  • ros2 service type <service_name>
  • ros2 service type /clear
• Find service by type
  • ros2 service find <type_name>
  • ros2 service find std_srvs/srv/Empty
• Show service type structure
  • ros2 interface show <type_name>.srv where request and response structure is separated by ---
  • ros2 interface show std_srvs/srv/Empty.srv
  • ros2 interface show turtlesim/srv/TeleportAbsolute.srv
  • ros2 interface show turtlesim/srv/Spawn
• Call service
  • ros2 service call <service_name> <service_type> <arguments>
  • ros2 service call /clear std_srvs/srv/Empty
  • ros2 service call /spawn turtlesim/srv/Spawn "{x: 2, y: 2, theta: 0.2, name: ''}"
• Get param list
  • ros2 param list
• Get param value
  • ros2 param get <node_name> <parameter_name>
  • ros2 param get /turtlesim background_g
• Set param value
  • ros2 param set <node_name> <parameter_name> <value>
  • ros2 param set /turtlesim background_r 150
• Dump node parameters
  • ros2 param dump <node_name>
  • ros2 param dump /turtlesim
• Start node using parameters from dumped file
  • ros2 run <package_name> <executable_name> --ros-args --params-file <file_name>
  • ros2 run turtlesim turtlesim_node --ros-args --params-file ./turtlesim.yaml
• Get list of node actions
  • ros2 node info /turtlesim
  • ros2 node info /teleop_turtle
• Get list of all actions
  • ros2 action list
  • ros2 action list -t to also show action types
• Get action info
  • ros2 action info /turtle1/rotate_absolute
• Get action interface info
  • ros2 interface show turtlesim/action/RotateAbsolute
• Call action
  • ros2 action send_goal <action_name> <action_type> <values>
  • ros2 action send_goal /turtle1/rotate_absolute turtlesim/action/RotateAbsolute "{theta: 1.57}"
  • ros2 action send_goal /turtle1/rotate_absolute turtlesim/action/RotateAbsolute "{theta: 3.14}" --feedback to also get feedback
• Run rqt console
  • ros2 run rqt_console rqt_console
• Start node
  • ros2 run rqt_console rqt_console
• Launch launch file
  • ros2 topic pub -r 1 /turtlesim1/turtle1/cmd_vel geometry_msgs/msg/Twist "{linear: {x: 2.0, y: 0.0, z: 0.0}, angular: {x: 0.0, y: 0.0, z: -1.8}}"
• Record topic to bag
  • ros2 bag record <topic_name> to record a topic
  • ros2 bag record /turtle1/cmd_vel
  • ros2 bag record -o subset /turtle1/cmd_vel /turtle1/pose top choose filename subset and record multiple topics
• Get bag info
  • ros2 bag info <bag_file_name>
  • ros2 bag info subset
• Play back bag recording
  • ros2 bag play <bag_file_name>
  • ros2 bag play subset

Starts two turtlesim nodes with different namespace names and a mimic node that makes the second turtle mimic first one.

from launch import LaunchDescription
from launch_ros.actions import Node

def generate_launch_description():
    return LaunchDescription([
        Node(
            package='turtlesim',
            namespace='turtlesim1',
            executable='turtlesim_node',
            name='sim'
        ),
        Node(
            package='turtlesim',
            namespace='turtlesim2',
            executable='turtlesim_node',
            name='sim'
        ),
        Node(
            package='turtlesim',
            executable='mimic',
            name='mimic',
            remappings=[
                ('/input/pose', '/turtlesim1/turtle1/pose'),
                ('/output/cmd_vel', '/turtlesim2/turtle1/cmd_vel'),
            ]
        )
    ])

• Install
  • sudo apt install tmux
• Start
  • tmux
• Split terminal
  • horizonal ctrl+b %
  • vertical ctrl+b "
• Manage windows
  • create ctrl+b c
  • close exit
  • rename ctrl+b ,
• Navigate
  • between panels ctrl+b ARROWS
  • between windows ctrl+b N where first N=0, second N=1 etc

https://docs.ros.org/en/foxy/Installation/Ubuntu-Install-Binary.html#linux-install-binary-install-missing-dependencies

/opt/ros/foxy

• sudo apt install -y python3-rosdep
• rosdep update
• rosdep install --from-paths /opt/ros/foxy/share --ignore-src --rosdistro foxy -y --skip-keys "console_bridge fastcdr fastrtps osrf_testing_tools_cpp poco_vendor rmw_connextdds rti-connext-dds-5.3.1 tinyxml_vendor tinyxml2_vendor urdfdom urdfdom_headers"

https://docs.ros.org/en/foxy/Tutorials/Workspace/Creating-A-Workspace.html

• mkdir -p ~/dev_ws/src
• cd ~/dev_ws/src
• git clone https://github.com/ros/ros_tutorials.git -b foxy-devel
• rosdep install -i --from-path src --rosdistro foxy -y
• colcon build
• open new terminal to source overlay
• cd ~/dev_ws

• create workspace directory mkdir ros2_ws etc
• create "src" in this directory
• copy the library/package into src
• rosdep install -i --from-path src --rosdistro foxy -y to install dependencies
• cd back to workspace and run colcon build to build the package

• https://github.com/ros-teleop/teleop_tools/tree/foxy-devel
• https://ubuntu.com/blog/the-teleop_tools-arrive-in-ros-2-dashing
• ros2 run mouse_teleop mouse_teleop
• ros2 run mouse_teleop mouse_teleop --ros-args -r holonomic:=true
• ros2 topic echo /mouse_vel

• cd ~/rosbot/experiments/test_odrive_ros2/
• ros2 run odrive_ros2 odrive_node
• ros2 service call /connect_odrive std_srvs/srv/Trigger
• ros2 service call /request_state odrive_interfaces/srv/AxisState "{axis: 0, state: 8}" (not needed if started in closed loop control)
• ros2 service call /velocity_cmd odrive_interfaces/srv/VelocityControl "{axis: 0, turns_s: 0.5}"
• ros2 topic echo /barrery_percentage (typo.. and not sure of the format, returns something like 3.5)
• ros2 topic echo /joint_state

• https://www.stereolabs.com/docs/ros2/rviz2/

• https://ros-controls.github.io/control.ros.org/getting_started.html
• https://github.com/ros-controls/ros2_control
• https://github.com/ros-controls/ros2_controllers
• https://github.com/ros-controls/ros2_control_demos
• https://github.com/ros-controls/ros2_controllers/tree/master/diff_drive_controller
• http://wiki.ros.org/urdf
• https://github.com/ros-controls/roadmap/blob/master/design_drafts/components_architecture_and_urdf_examples.md
• https://github.com/ros-controls/ros2_control_demos/blob/master/ros2_control_demo_bringup/config/diffbot_diff_drive_controller.yaml
• https://github.com/ros-controls/ros2_control_demos/tree/master/ros2_control_demo_description/diffbot_description
• https://github.com/ros-controls/ros2_control_demos/blob/master/ros2_control_demo_bringup/launch/diffbot_system.launch.py
• https://ros-controls.github.io/control.ros.org/ros2_control/ros2controlcli/doc/userdoc.html#ros2controlcli-userdoc CLI
• cd ~/rosbot/experiments/test_odrive_ros2_control/
• sudo apt install ros-foxy-ros2-control ros-foxy-ros2-controllers
• ros2 launch odrive_bringup odrive.launch.py enable_joint1:=true
• ros2 topic pub -r 100 /joint0_velocity_controller/commands std_msgs/Float64MultiArray "data: [1]"
• ros2 topic pub -r 100 /joint1_velocity_controller/commands std_msgs/Float64MultiArray "data: [-1]"

• copy repo https://github.com/ros-controls/ros2_control_demos
• create workspace folder, move demo repo folders under src
• cd ros2_control_demos/
• rosdep install -i --from-path src --rosdistro foxy -y
• colcon build
• open new terminal
• cd ros2_control_demos/
• . install/local_setup.bash
• ros2 launch ros2_control_demo_bringup diffbot_system.launch.py start_rviz:=true
• ros2 control list_hardware_interfaces to list ros control hardware interfaces
• ros2 control list_controllers to list ros control controllers
• publish velocity command

ros2 topic pub --rate 30 /diff_drive_controller/cmd_vel_unstamped geometry_msgs/msg/Twist "linear:
 x: 0.7
 y: 0.0
 z: 0.0
angular:
 x: 0.0
 y: 0.0
 z: 1.0"

• control with mouse_teleop, remapping /mouse_vel to /diff_drive_controller/cmd_vel_unstamped
• ros2 run mouse_teleop mouse_teleop --ros-args -r /mouse_vel:=/diff_drive_controller/cmd_vel_unstamped

• Run the following in terminal
• wget -qO- https://raw.githubusercontent.com/cra0zy/code-nautilus/master/install.sh | bash

• ssh-keygen -t rsa to create ssh key in ~/.ssh if not already present
• cat ~/.ssh/id_rsa.pub to get public key from computer that wants to access robot
• add the public key to robot's ~/.ssh/authorized_keys file
• create ~/.ssh/config file on the remote computer with contents like

Host rosbot
    HostName rosbot
    User ubuntu

• ssh rosbot to open ssh connection to robot using the configuration and ssh key

cd ~/dev_ws/src ros2 pkg create --build-type ament_cmake <package_name> ros2 pkg create --build-type ament_cmake --node-name my_node my_package ros2 pkg create --build-type ament_cmake --node-name talker test_chat

https://github.com/ros2/rclcpp http://docs.ros2.org/latest/api/rclcpp/ http://wiki.ros.org/std_msgs

https://github.com/RobotWebTools/rclnodejs https://github.com/RobotWebTools/rclnodejs-cli http://robotwebtools.org/rclnodejs/docs/0.20.0/index.html https://github.com/RobotWebTools/rclnodejs/tree/develop/example npx generate-ros-messages