Planning dextrous operations using physical models

Planning robust grasping operations involving a dextrous robotics hand and an object located in a three dimensional workspace requires the combination of two main types of techniques, a geometric reasoning technique aimed at producing a grasping strategy (preshape of the hand, grasping parameters, type of motion to execute), and a physically based technique, allowing the analysis of the dynamic object/hand interactions. The paper focuses on the second type of technique which is clearly required to conclude on the feasibility of the chosen grasping strategy (stability in particular) and to determine the execution parameters of the selected grasp (type of control to apply onto the hand in particular). The purpose of the paper is to propose a new technique based upon the concept of “physical models” for solving this problem. The authors show how physical models can be constructed and used to solve the associated stability and control strategy problems. The authors also show how the related techniques have been combined with more classical geometric methods to solve the whole problem