This paper evaluates state-of-the-art contact models at predicting themotions and forces involved in simple in-hand robotic manipulations. Inparticular it focuses on three primitive actions --linear sliding, pivoting,and rolling-- that involve contacts between a gripper, a rigid object, andtheir environment. The evaluation is done through thousands of controlledexperiments designed to capture the motion of object and gripper, and allcontact forces and torques at 250Hz. We demonstrate that a contact modelingapproach based on Coulomb's friction law and maximum energy principle iseffective at reasoning about interaction to first order, but limited for makingaccurate predictions. We attribute the major limitations to 1) thenon-uniqueness of force resolution inherent to grasps with multiple hardcontacts of complex geometries, 2) unmodeled dynamics due to contactcompliance, and 3) unmodeled geometries dueto manufacturing defects.
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