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OS: Ubuntu 22.04
Distro: Humble

Hi, I am trying to use MoveIt2! to control a custom robot. I have created a simple URDF files to test how to work with ros2_control. I have created a hardware interface component. When running the trajectory, it seems that the joint_limits that I have specified in the URDF file is not being enforced.

  <?xml version="1.0"?> <robot name="one_joint"> <link name="base_link"> <visual> <geometry> <cylinder length="0.6" radius="0.2"/> </geometry> </visual> <collision> <geometry> <cylinder length="0.6" radius="0.2"/> </geometry> </collision> </link> <link name="rotate_joint"> <visual> <geometry> <box size="0.6 0.1 0.2"/> </geometry> <origin rpy="1.57075 0 0" xyz="0.3 0 0"/> </visual> <collision> <geometry> <box size="0.6 0.1 0.2"/> </geometry> </collision> </link> <joint name="base_to_rotate_joint" type="revolute"> <!-- <safety_controller k_velocity="4" soft_lower_limit="-0.20" soft_upper_limit="0.20" /> --> <parent link="base_link"/> <child link="rotate_joint"/> <origin xyz="0 0 0.35"/> <axis xyz="0 0 1"/> <limit effort="87" lower="-6" upper="6" velocity="0.272645" /> </joint> <ros2_control name="grab_joint1" type="actuator"> <hardware> <plugin>grab_hardware_interface/GrabJointHardware</plugin> </hardware> <joint name="base_to_rotate_joint"> <command_interface name="position"> <param name="min">-6</param> <param name="max">6</param> </command_interface> <command_interface name="velocity"> <param name="min">-0.27</param> <param name="max">0.27</param> </command_interface> <command_interface name="acceleration"> <param name="min">-0.27</param> <param name="max">0.27</param> </command_interface> <state_interface name="position"/> <state_interface name="velocity"/> </joint> </ros2_control> </robot>

Going through the ros2_control PRs I am completely confused on how to enforce the joint_limits. Can anyone shed some light on this.

Originally posted by Cryoschrome on ROS Answers with karma: 75 on 2022-07-20

Post score: 1

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The ros2_control joint_trajectory_controller actually doesn't enforce joint limits at all right now :'| There's some work being done to fix that but it's not ready yet.

So, MoveIt is the module that's actually obeying joint limits when it creates a trajectory. MoveIt is not aware of these limit tags that you have put in the <ros2_control> block.

For MoveIt, you should specify the joint limits like this:

https://github.com/ros-planning/moveit_resources/blob/57a44ca62132802e4d6155801a0c867edb247db9/panda_description/urdf/panda.urdf#L57

Or you can put the joint limits in joint_limits.yaml --> this will override whatever you have in the URDF.

Originally posted by AndyZe with karma: 2331 on 2022-07-20

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Comment by Cryoschrome on 2022-07-21:
Thank you for the reply. I got it working!

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