Variable Dynamic Assist Control on Haptic System for Human Adaptive Mechatronics

Based on a new concept of a human-in-the-loop system called Human Adaptive Mechatronics(HAM), an assist-control for a force/vision interactive haptic system is discussed in this paper. An assist-control scheme proposed here consists of a ´variable dynamics´ unit and an online identifier of an operator´s control characteristics. The former unit is realized by tuning an impedance of the haptic device´s virtual model according to the identified operator´s parameters. At a stage of the controller design, a human and a machine are considered as a plant and a controller respectively. A role of the controller is to tune dynamics of the machine so as to enhance operator´s control performance. The tuning law is derived by utilizing a Lyapunov candidate function. We developed a HAM-haptic device test system, executed evaluation experiments with the apparatus, and analyzed the measured data. It was confirmed that the operator´s characteristics can be estimated sufficiently and that operator´s performance was enhanced by the variable dynamics assist-control.