CLEARPATH TurtleBot 4 Lite, User Manual

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Software Modifications
Velocity and acceleration limits should be set appropriately to maintain stability when driving the
robot. Otherwise you may find that the robot will shake, stall, or not drive as commanded.
Acceleration Limits
The acceleration limit on the Create® 3 can be changed using the wheel_accel_limit parameter
of the motion_control node.
ros2 param set /motion_control wheel_accel_limit 300
The acceleration value can be between 1 and 900.
Note
The wheel_accel_limit is applied to both acceleration and deceleration. If you set it too low, the
robot will stop very slowly.
Velocity Limits
The Create® 3 has linear velocity limits of 0.31 m/s with safety enabled, and 0.46 m/s with
safety overridden. The angular velocity is limited to 1.9 rad/s. For heavy payloads you may want
to limit this further. The method to do this will vary based on how you are
driving the robot.
Keyboard Teleoperation
If you are using the teleop_twist_keyboard ROS2 node, you can follow the CLI instructions to
reduce linear and angular velocities.
Joystick Teleoperation
To limit the teleop_twist_joy velocities you will need create a modified version the TurtleBot4
controller config file . The scale_linear.x value limits the linear velocity, and the
scale_angular.yaw value limits the angular velocity.
Once you have created the config file, you can launch joy_teleop and set the controller_config
parameter to the full path of your new config file.
ros2 launch turtlebot4_bringup joy_teleop.launch.py controller_config:=/path/to/config.yaml