Jetbot-ros2

This is an implementation of a mobile robot in ros2. The software includes the following functionalities:

• Teleoperation through websockets with live video feed using webrtc (aiortc).

• Integration of Intel realsense d435 and t265 cameras for depth estimation and localization respectively.

• 2D SLAM with cartographer.

• 3D SLAM using rtabmap.

I used the Xiaor Geek Jetbot as a base platform and modified it to include a wide-angle camera, as well as the Intel Realsense d435 and t265.

Requirements

• ROS2 eloquent or foxy.
• librealsense2.
• Motor Drivers - In this case, installed from the jetbot's repository.

Installation

1. Clone this repo and its submodules.

   git clone --recurse-submodules https://github.com/cameronmcnz/surface.git 

Teleoperation support

2. Install aiortc for webrtc support.

   pip3 install crc32c==2.0
   pip3 install aiortc
   pip3 install aiohttp

3. Install pyfakewebcam so that camera frames can be modified inside a ROS2 node and then shared through webrtc:

   apt-get install v4l2loopback-utils
   pip3 install pyfakewebcam

4. Write a service that creates fake webcam devices that can be used to share camera frames.

   gedit /etc/rc.local

   Copy and paste in file:

   #!/bin/sh -e
   modprobe v4l2loopback devices=2 # will create two fake webcam devices
   exit 0

   Save the file and make it executable with this command:

   chmod +x /etc/rc.local

SLAM Support

1. Install Cartographer.

   sudo apt-get install ros-<distro>-cartographer

2. Install rtabmap and rtabmap_ros following these instructions in the branch ros2.

Build ros 2 workspace

```bash
cd dev_ws
source /opt/ros/<distro>/setup.bash
colcon build
. /install/setup.bash
```

Run

1. Run local teleoperation server.

   python3 local_server/webcam.py

   In a browser, open the teleoperation interface by going to: <jetson_nano's ip-address>:8080

2. In a new terminal, run the motion control launchfile to start streaming video and receiving motion commands.

   ros2 launch motion_control jetbot_launch.py

3. Run SLAM.

   • For 2D-SLAM, in another terminal:

   ros2 launch realsense_ros2 slam_cartogrepher_launch.py

   • For 3D-SLAM, in another terminal:

   ros2 launch realsense_ros2 slam_rtabmap_launch.py

   3D Dense SLAM is too resource consuming for the Jetson Nano, in this case it is recommended to run it on a remote host. For this, simply set the same DOMAIN_ID on both the Jetson Nano and the remote host. (e.g. export DOMAIN_ID=0) and run the cameras in the Jetson Nano:

   ros2 launch realsense_ros2 realsense_launch.py

   Comment the nodes corresponding to the cameras on the host and run the rtabmap launch:

   ros2 launch realsense_ros2 slam_rtabmap_launch.py

Results

Video