H∞ Loop Shaping Bilateral Controller for a Two-Fingered Tele-Micromanipulation System

Recent developments on micromanipulation and Internet technologies allow potential impacts on networked microautomation of small industrial products. However, reliable and efficient microteleoperation systems with haptic feedback over the Internet face strong problems due to microenvironment variations, the scaling effect problem between worlds with different physical characteristics, and time delays in communication lines. Taking into account these constraints, a force-reflecting macro-microteleoperator controller is designed based on the framework H_infin loop-shaping procedure approach. This approach allows a convenient way to tradeoff the robustness for a prespecified time delay margin, variation of force scaling factors, and uncertainties in environment models. The experimental results clearly show that the proposed approach ensures the stability robustness against time delays and scaling factors.