Quasi-dynamic manipulation of constrained object by robot fingers in assembly tasks

Abstract

The authors discuss how to manipulate an object in contact with the fixed environment with robot-fingers to perform a planned assembly operation successfully. First, the region of possible fingertip force to balance the reaction force from the environment (quasi-static analysis) is explicitly represented to ensure that the moving object is manipulated correctly. Next, by considering the assembly operation in quasi-dynamic way (i.e., assuming that the velocity of the motion is small enough to be neglected but its acceleration is not negligible), the region of feasible fingertip forces to operate the object is described. According to the region of possible finger forces, the corresponding feasible range of the fingertip positions on the object surface can be obtained. And the difference between the fingertip position obtained by the quasi-dynamic analysis and the fingertip position obtained by the quasi-static analysis is shown. Lastly, the validity of this quasi-dynamic method is verified by serval experiments., All discussions are on the assumptions that objects are polyhedra and their notions are planar and frictionless, and its velocity is small enough.