Force Control of Kinematically Constrained Mechanisms in the Presence of Contact Point Disturbances

抄録

This paper presents a discussion of the issues related to force control in closed-loop kinematically constrained mechanisms. Unlike many of the analyses presented in robotics literature, which tend to model the contact with a stiff, but finite, compliance, the analysis in this paper focuses on the issues particular to mechanisms in which the contact relationship is kinematic. Motions of these kinematically constrained points thus give rise to contact force fluctuations which are related to both the inertial properties of the mechanism and the nonlinear kinematics. By modelling the constrained system as a closed-loop mechanism, it is possible to take into account both the kinematic constraint and the dynamic properties of the mechanism in order to derive force control laws which can be used to regulate contact forces even in the presence of contact point disturbances. Simulations and experiments with a simple one-link constrained mechanism underscore the importance of inertial force and contact point disturbance consideration in force control.