ROS STorM32 Gimbal Driver

This is a driver to communicate with STorM32 gimbal controllers.

You MUST configure your gimbal with the Windows app before using this package.

This package has been tested on ROS Humble Hawksbill on Ubuntu 22.04.

Setting up

You must clone this repository as storm32_gimbal into your workspace:

git clone https://github.com/ncsuarc/storm32_gimbal

Dependencies

Before proceeding, make sure to install all dependencies by running:

rosdep update
rosdep install storm32_gimbal

Compiling

You must compile this package before being able to run it. You can do so by running:

colcon build --symlink-install

from the root of your workspace.

Running

To run, the workspace environment must be overlaid.

. install/setup.bash

Simply launch the storm32_node.py node as such:

ros2 run storm32_gimbal gimbal

You can change the port and TF frame ID by passing them as parameters

ros2 run storm32_gimbal storm32_node.py port:=<device_path> frame:=<frame_name>

A sample launch file is available in the launch directory and can be run with:

ros2 launch storm32_gimbal gimbal_launch.py

Interfacing

The gimbal_ref frame

All orientations used by this package are relative to a global reference frame called gimbal_ref. This reference frame is attached to the gimbal, and has a z axis always pointing away from the center of the earth (i.e. it does not pitch or roll, but can yaw).

Topics

This package publishes to two topics:

• ~camera_orientation: The IMU1 readings as a QuaternionStamped message (i.e. the orientation of the gimballed link relative to the global gimbal_ref frame). Since the link is stabilized, this should always be approximately the target orientation of the gimbal.
• ~controller_orientation: The IMU2 readings as a QuaternionStamped message (i.e. the orientation of the STorM32 board relative to the global gimbal_ref frame). This should represent the orientation of the gimbal and is not stabilized.

You can also set a new target orientation relative to the gimbal_ref frame by publishing a GimbalOrientation message to the ~target_orientation topic. The orientation field is expected to be relative to the gimbal_ref frame, and the unlimited field defines whether the controller should attempt to limit its rotation to hard set limits on the STorM32 controller.