Haptic tele-operation system control design for the ultrasound task: A loop-shaping approach

This paper introduces a step-by-step frequency domain loop-shaping procedure for tele-operation system controllers, in particular for the three-channel Environment Force Compensation (EFC) control architecture. The framework is explained by designing a controller for a tele-operated 5-DOF probe for ultrasound echo-cardiography. Models of the tele-operation system components are created and performance requirements are specified. A control design procedure is proposed using a generic tele-operation block-scheme. In this procedure, the choice for the EFC control architecture is underpinned and guidelines for the loop-shaping of this tele-operation controller for performance and stability robustness are given. The designed controllers are tuned using the introduced procedure. Passivity, performance and stability robustness of the newly designed controller are evaluated using experiments.