Arm on a mobile manipulator executes an opposite behaviour through MoveIt

I am trying to manipulate an arm placed over a mobile base using MoveIt. Whenever I try to set goal for the end effector from Rviz visualiser or MoveIt commander, the arm moves in exactly opposite direction. For instance, if I give a goal to move 5 units in positive x-direction then, arm moves in negative x-direction. I have used semu-robotics extension for effort-joint-controller control from MoveIt.

I am not able to understand where does this 180 deg shift is coming. Is it because of some axis issue in URDF or joints or in MoveIt control?

Below are the system specifications:

Isaac Sim 2022.1.1
Ubuntu - 20.04
CPU - Intel Core i7
Cores - 24
RAM - 32 GB
GeForce RTX 3060-Ti
VRAM - 16GB
Disk - 2TB SSD

Hi @deveshkumar21398

As the extension creator, I have the following comment in case it is useful to you:

The implementation of the FollowJointTrajectory ROS action service, in this user extension, is only made for position control. Then, only position information from JointTrajectoryPoint message is used. Velocity and effort values are ignored if they exist.

I encourage you to contribute to the extension if you wish to add new features :)


In any case, can you please share a minimal example to reproduce this behavior? If so please include the MoveIt configuration and any other necessary files or resources.

Hi @toni.sm thank you for your quick response. A quick update that the opposite behaviour issue is now resolved. I had re-setup the moveit config using setup assistant. Meanwhile, I was negating the joints axis as a workaround till now, however, re-setting up fixed it.

Sure, this extension has been quite useful till now.

Thank you!

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