Something strange happens with IK

[MaJiamu]

Hello, I created a simple scene with IK, and after the simulation running, I move the target dummy, the wrench_joint2 and wrench_joint3 working well. However, the wrench_joint1 can only rotate a small degree, and this result in the failure for tip to track the target.

I put the link of the scene here, and thanks for anyone help me with that.
https://drive.google.com/file/d/1MPv4Qb ... sp=sharing

Version Info: CoppeliaSim Edu,Version 4.6.0(rev18) 64bit in Windows 10.

[coppelia]

Hello,

your mechanism has exactly 3 DoF, you however have a pose constraint (i.e. for 6 DoFs). Simply replace simIK.constraint_pose with simIK.constraint_position

Cheers