Fundamentals and analysis of compliance characteristics for multifingered hands

We provide a guideline for specifying compliance characteristics in the operational space of multifingered hands. From the analysis of the stiffness relation between the operational space and the fingertip space of multifingered hands, it is shown that some of the coupling stiffness elements cannot be planned arbitrarily. An independent finger-based compliance control method to achieve the given compliance characteristics is presented. Through the analytical results, it is concluded that the operational stiffness matrix should be carefully specified by considering the grasp geometry of multifingered hands for successful grasping and manipulation tasks, and the three-dimensional compliance control can also be achieved by a five-fingered human-like hand.