tailieunhanh - Model reference adaptive control of a haptic feedback device for improving force performance

In this paper, a new adaptive control algorithm of a haptic feedback device is analyzed. Forces applied to the haptic device through human hand movements are modeled as disturbances and compensated in the force control action. | SCIENCE & TECHNOLOGY DEVELOPMENT, Vol 17, 2014 Model reference adaptive control of a haptic feedback device for improving force performance • Vu Minh Hung • Trinh Quang Trung PetroVietnam University (PVU) (Manuscript Received on July 23th, 2013; Manuscript Revised January 14th, 2014) ABSTRACT: In this paper, a new adaptive control algorithm of a haptic feedback device is analyzed. Forces applied to the haptic device through human hand movements are modeled as disturbances and compensated in the force control action. A model reference adaptive control (MRAC) scheme is proposed to improve force tracking performance. A separate reference model for every DOF is selected to satisfy rising time, settling time, peak time, and overshoot requirements. General adaptive control laws are developed for tuning gains in the control transfer functions based on the reference model and the force sensor and encoder readings in real time. These control gains cover force tracking performance and compensate human hand disturbances while providing robustness to sensor noise. Stability of the control system is shown analytically. Convergence and boundedness of control gains are also shown through experiments. Keywords: Adaptive force control, haptic device, haptic teleoperation, MRAC, masterslave control, human hand, haptic device modeling. 1. INTRODUCTION Haptic feedback devices have many useful applications such as surgical teleoperation systems. In which a surgeon can use the haptic device to operate a surgical robot working with patients. The haptic device can work as a master to provide desired trajectories and forces for a slave robot. Control of haptic feedback devices has become active research areas. The control algorithm should satisfy the objective of accurate force sensing from the desired forces. The user should feel actual forces from the desired forces not those of the structure of the Trang 102 haptic device. Impedance force control and admittance force .