I have a pair of objects. The first one is a simple box (+rigidbody, kinematic=true). The second one is a model from ShadowDemoProject demo, called officeChair. Then I click the play button and the chair fall on the box... However the box a little bit has entered into the box.
How can I prevent entering a rigid body into another one ?
Use a smaller MinPenetrationForPenalty setting in the physics settings. Careful about setting it too low though.
The isKinematic Script Reference explains that it:
Controls whether physics affects the rigidbody.
If isKinematic is enabled, Forces, collisions or joints will not affect the rigidbody anymore.
If you want them to simulate physics collisions, you can't have kinematic set to true.