New user constantly getting "IK Failed! Cannot find valid solution."

[rafaelBauer]

Hello, this is not a bug, but more a call for help :)

I am new into robot control and looked through the examples and I have been trying to create a motion plan, but I cannot really make it work.

My setup is a bit different. I have a panda robot and I am using ManiSkill. But somehow I am struggling to make a simple trajectory.

My move_group is the panda_hand_tcp and initially its pose is Pose([0.00369545, 0.029311, 0.184837], [0.00760545, 0.999395, 0.0339194, 0.000981587]) (I got this information from SAPIEN Viewer). I am trying to make a planning to Pose([0, 0, 0.05], [0, 1, 0, 0]), but I am constantly getting this inverse kinematics error.. I am not sure if there is any configuration I am doing wrong.

My ManiSkill environment control_mode is pd_ee_delta_pose.

I appreciate if anyone has a tip on how I could proceed, or debug what is my problem :)

[rafaelBauer]

Finally got it working. My problem was my control mode. I changed to pd_joint_pos and it worked perfectly :)

EDIT: Finally got it working. I had two problems.

1. My target pose
2. ManiSkill control mode.

The target pose was likely leading to a collision, since I was trying to go to [0, 0, 0.5] and the reference is the robot base link. So I changed the target pose to Pose([0.615, 0, 0.5][0, 1, 0, 0]) and the planning was working.

Then I had a problem, that the actions were not really controlling the robot in a desired way. My actions are coming only from the position of the planning. So I changed the ManiSkill control_mode to pd_joint_pos and it worked perfectly :)

[Lexseal]

Thanks for the follow-up! "IK Failed! Cannot find valid solution" can also often be triggered by collision. I am not sure why the control mode in maniskill should have anything to do with IK in mplib.

[rafaelBauer]

Oh no, I also changed the pose. I updated my comment from before just to keep this complete. Thanks for the reply!