Force sensorless bilateral control using a dynamical asymmetric compensator

Among other bilateral control systems, those of symmetric type have advantage of simple structure, force sensorless and readiness to stabilize. However, a symmetric type bilateral system is known to have poor haptic performance. In this paper, we propose a bilateral system design without force sensor, based on a generalized system structure of master slave systems. Force feedback and position tracking performance are taken into account by H2 performance at frequency range of the desired haptic transfer, and influence of the measurement noise is suppressed by H-infinity condition. Such a multi-objective controller is designed by solving a semidefinite programming problem. The derived controller tends to have large condition number; we truncate balanced realization of the controller to obtain feasible feedback systems. Effectiveness of the proposed approach is illustrated by numerical studies in time as well as frequency domains, and also experiments.