미지 물체의 구속상태에 관한 실시간 추정방법

Abstract

Control of a multi-?ngered robotic hand is usually based on the theoretical analysis for kinematicsand dynamics of ?ngers and of object. However, the implementation of such analyses to robotic handsis di±cult because of errors and uncertainties in the real situations. This article presents the controlmethod for estimating the kinematic constraint of an unknown object by active sensing. The experimentalsystem has a two{?ngered robotic hand suspended vertically for manipulation in the vertical plane. The?ngers with three degrees{of{freedom are driven by wires directly connected to voice{coil motors withoutreduction gears. The ?ngers are equipped with three{axis force sensors and with dynamic tactile sensorsthat detect slippage between the ?ngertip surfaces and the object. In order to make an accurate estimationfor the kinematic constraint of the unknown object, i.e. the constraint direction and the constraint center,four kinds of the active sensing and feedback control algorithm were developed: two position{basedalgorithms and two force{based algorithms. Furthermore, the compound and e??ective algorithm was alsodeveloped by combining two algorithms. Force sensors are mainly used to adapt errors and uncertaintiesencountered during the constraint estimation. Several experimental results involving the motion of liftinga ?nger o?? an unknown object are presented.