Variable Impedance Characteristics of Human Arms in Cooperative Motion by Two Humans and Its Application To the Control of a Robot

Abstract

This paper describes the cooperative characteristics of carrying an object by two humans and its application to the control of a robot for performing the cooperative task with a human. First, the cooperative task is modeled on one dimensional horizontal motion and the experimental condition for the analysis of the cooperative motion by two humans. Secondly, variable damping characteristics of the human arm are found in the experimental cooperative motion and are expressed as an optimal trajectory of the damping factor using a performance index which evaluates both the change speed and the magnitude of the damping effect. Thirdly, a variable impedance control method of a robot is constructed using the optimal trajectory and it is shown that a human manipulates the robot like as human and human cooperation. Finally, it is found that even if one of the parameters making the optimal trajectory changes to high values, the smooth cooperation between the human and the robot keeps successfully.