Quasi-Dynamic Manipulation of Constrained Object by Multiple Robot Fingers.

Abstract

In order to reduce the uncertainty in assembly operations, it is effective to bring a part into contact with a fixed environment and guide it on the contacting planes into a designated position.This paper considers using robot fingers to manipulate a part in contact with a fixed environment to perform a planned assembly operation. We believe that assembly operations by robot fingers have much potential compared to those of conventional grippers in the sense of dexterity, preciseness and flexibility. However, in order to perform assembly operations by robot fingers, it is necessary to plan fingertip positions on the part to be manipulated. First, in this paper, the region of feasible fingertip force needed to balance the reaction force from the environment is explicitly represented to ensure that the part is manipulated stably, when the static and dynamic friction among the objects are considered. Next, considering the assembly operation quasi dynamically (i. e. the square term of the motion velocity is small enough to be neglected but its acceleration will be considered), the region of feasible fingertip force needed to manipulate the part to its designated direction is described. According to this region of feasible fingertip force, the corresponding feasible fingertip position range on the object surface can be obtained.