Why does the act ofextracting cause mymodel to crash?

[luocl4]

 When my robot's gripper attempts tograsp a stationary wooden block,sometimes the gripper's structure gets damaged and strange disturbances occur. However, this is arandom outcome, and each time it happens, the result is different.

added a suction cup node in the proto.

[CoolSpy3]

It sounds like the physics engine being weird. It can sometimes cause erratic behavior in complex simulations or when objects are interacting in weird ways. Would it be possible for you to post your project folder/world file so we can reproduce the problem?