Coordinated Motion Planning of Independent Manipulators in Precision Manipulation

This article investigates the coordinated motion planning of independent manipulators in the domain of precision manipulation, where forces are considered in the level of tens or hundreds of milliNewtons. Independent manipulating is crucial in randomly combining robot arms to temporarily fulfill certain tasks. We study the cases where a part of task information is known to each manipulator and yet no communication exists between them. In the coordinated structure, the leading manipulator plans its movement according to the desired state and its evaluation of the object force. The follower needs to compensate for the offset errors, estimate the intention of the leader, evaluate its confidence on the estimation, and plan its movement accordingly. The handling of special states, i.e., zero force feedback, is also discussed. Experiments are carried out to demonstrate the validation of the proposed method.