Grasping force measurement for dynamic grasp stability assessment

Grasping dynamic stability is an important quality index for robotic grasping. Previous studies on the grasping stability usually consider the problem under the quasi-static assumption. This paper systematically investigates the grasping dynamic behavior from both theoretical and simulation aspects for the purpose of practical measurements. The dynamic stability of a grasping system is related to the contact type between the grasped object and the fingers, the grasping configuration, the control law of the fingers, and the passive compliance of the fingers. Starting from the dynamic equations of the grasping system, Liapunov stability theory is used to study the grasping dynamic stability problem. Simulation was conducted in support of the theoretical hypothesis. A gripper system was developed incorporating real time three-dimensional grasp force sensing for each of the fingers with some initial experimental results given.