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Version: 2.0.0

Bluefox2 IMU

This is a package for publishing the data from the IMU mounted on a Bluefox2 MRS module.

Installation​

The driver is part of the full installation of the mrs system (ros-jazzy-mrs-uav-system-full). If missing, install it by running the following command (it is part of the mrs_serial package together with other nodes):

sudo apt install ros-jazzy-mrs-serial

You also need to install udev rules, so you don't have access permission errors. Copy the udev rule file from package's install/udev directory to /etc/udev/rules.d/ and refresh udev daemon:

sudo cp install/udev/* /etc/udev/rules.d/
sudo udevadm control --reload
sudo udevadm trigger

Startup​

First, you have to define environment variable 'UAV_NAME'. For example, you can do it by:

export UAV_NAME=uav1

or you can add it to your .bashrc to make it more permanent:

echo "export UAV_NAME=uav1" >> ~/.bashrc

If you do not have this environment variable set, you will see this error message:

Caught exception in launch (see debug for traceback): environment variable 'UAV_NAME' does not exist

Now you can launch the IMU node:

ros2 launch mrs_serial vio_imu.launch.py

The default device for the IMU is /dev/ttyACM0. If the node can't find this device and you are seeing coresponding error messages in the terminal, you can search for the IMU device and specify it:

ros2 launch mrs_serial vio_imu.launch.py device:=/dev/tty...

Alternatively, you can define the udev rule for your device.

Custom configs​

You can provide a custom config to the launch file as

ros2 launch bluefox2 single.launch.py custom_config:=custom_config.yaml

The custom configs allows you to define your own parameters and also to remap the outgoing topics:

uav_name: uav1
enable_profiler: false
portname: /dev/ttyACM0
baudrate: 460800
verbose: false
use_timeout: false
serial_rate: 460800
desired_publish_rate: 200   # 1000, 500, 200, 100, 50... floor(1000/desired_publish_rate)

Note: You cannot specify namespace in your custom config because this node is running as a composable node.

The desired_publish_rate determines how many messages will be skipped. If it is set to 500, then every other message is published. If it is set to 100, then only every 10th message is published. Skip factor is computed as floor(1000/desired_publish_rate), so it makes sense to only use the integer divisors: 1000, 500, 200, 100, 50...

In Docker​

Place the following compose session snippet into the example session:

  bluefox_imu:
    image: ctumrs/mrs_uav_system:stable
    network_mode: host
    volumes:
      - /dev/:/dev/ # besides setting 'privileged' flag to true, you also have to mount '/dev' to see device file
    privileged: true
    env_file:
      - ./stack.env
    command: bash -c "ros2 launch mrs_serial vio_imu.launch.py"

More info​

Check the following sources

GitHub Repository