Problem with getUserDefinedRobotPosition / joint positions

Technical Questions
7

Thank you @m.birkholz for pointing out this post for me. I am facing the same problem.

Note: I was able to separate another bug that at first seemed to be part of the same. It is covered in Capturing pose with a button, questions and troubles.

I’m working in the URCap for a control disc with 2 buttons that goes in between the wrist and the tool.
• One button is for freedrive.
• The other is for recording waypoints.

I’m having trouble creating the right pose for this waypoints.

  • I receive well the pose and joint positions via RT (30003 port). This data includes the TPC .

  • But, when I use createFixedPositionConfig I’ve come to the conclusion this method is expecting the pose without tool , just at the wrist.

    WaypointNodeConfig newWaypointNodeConfig = waypointNodeConfigFactory.createFixedPositionConfig(pose[0], jointPositions[0], blendParameters, motionParameters);

How I found out? Similarly to other entries in this post, I see this method is working fine with TCP = 0, 0, 0, 0, 0, 0.

But with any different TCP is not.

I’ve calculated ‘error’ XYZ distance and it matches to decimals with the TPC XYZ distance from the wrist.
The orientation angles I didn’t check it mathematically, but seem to me to be matching the TCP orientation.

Two ways to see it:

  1. It is a bug: @jbm Then, please UR team, fix it asap :grimacing:
    The createFixedPositionConfig method should use the TPC for calculations.
    Probably adding optional parameters to the method would do. Should include:

    • Manually defined TCP (0, 0, 0, 0, 0, 0 if not passed)
    • Option for ‘currently active TPC’
    • Maybe option for the ones defined in the installation? Not so sure of that

  2. It is intended to be like this, not taking the TPC into consideration: Then, we need to have pose_trans and pose_inv methods in Java asap. Can you help @jbm :grimacing:
    This would allow us (non matrix mathematisian experts in general, at least not me) to add a given TPC to have the rigth pose.
    There’s a post on this too: Pose_trans and pose_inv functions in URCap - #5 by dmartin

Thanks a lot folks!!