drive_base

This a ROS2 node for a drivebase using the Roboclaw motor controllers made by Basic Micro Motion Control.

Pre-Reqs

Roboclaw user Manual Before you use this package you need to calibrate the velocity PID on the Roboclaw. This will require the installation of their calibration software Motion Studio (Windows only).

Settings this project uses that need to be set in motion studio:

Control Mode: packet serial

Serial Packet Address: Right: 128, Left: 129

Baudrate: 115200

Additionally check that your encoders readings and motor directions line up in the software.

Usage

Just clone the repo into your colcon workspace. It contains the ROS node and the motor controller driver written by bmegli with a few added functionalities for speed control.

cd <workspace>/src
git clone https://https://github.com/ccresta1386/drive_base.git
cd <workspace>
colcon build

The package assumes you will be using USB control, make sure that ROS will have access to the "/dev/USBttyACMX" ports that your roboclaws are connected to.

Parameters

The launch file can be configure at the command line with arguments, by changing the value in the launch file or through the rosparam server.

Parameter	Default	Definition
encoder_scale	-2560	The encoder scale for used in calculation for ticks_to_m conversion, use this to calibrate odometry
debug	false	To print or not to print positional information for encoder calibration
wheel_radius	0.09915	Set this per your wheels
wheelbase_x	0.16312	Set this for your wheelbase measurement in the X direction
wheelbase_y	0.3458	Set this for your wheelbase measurement in the Y direction
omnidirectional	false	whether or not to use the omnidirectional driving

Topics

Subscribed

/cmd_vel (geometry_msgs/msg/Twist.msg)
Velocity commands for the mobile base.

Published

/wheel/odometry (nav_msgs/msg/Odometry.msg)
Odometry output from the mobile base. Note omnidirectional odometry is not currently implemented.