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

Cryptorchidism

The term cryptorchidism refers to the condition of abnormal testicular descent (TD). In this situation the testis is â\u80\u9chiddenâ\u80\u9d and it cannot be identified in its normal position that is inside the scrotum. In fact the term â\u80\u9ccryptorchidismâ\u80\u9d literally means â\u80\u9chidden testicleâ\u80\u9d and is often used interchangeably with the term â\u80\u9cundescended testicleâ\u80\u9d. A normal testicular function is guaranteed by its full descent into the scrotum. Undescended testes carry the risk of malignant transformation and loss of fertility. It is thus mandatory to recognize this condition in order to plan the surgical correction