Suction Cup

[Dong-Le-gnoD]

Hi folks,
I am working on simulation using suction cup to pick up a deformable object. At this moment, I've already had a basic setup, both the cup and object are using deformable properties from STLIB.

However, I was wondering that how do I attach the object to the suction cup after the collision. Could you suggest any idea for the operation? Also, what if I want to "turn off" the suction cup during the simulation to see the object drops, what should I do to archive that?

Thank you!