Acknowledgements
We thank the authors for the following models that we use in the unit tests.
The clamp c1 URDF model is designed by @yck011522.
The dms gripper mesh model is designed by @stefanaparascho.
The kuka_kr6_r900 URDF model is from @ros-industrial/kuka_experimental.
The universal_robot URDF model is from @ros-industrial/universal_robot.