Telemanipulator design for minimally invasive surgery

This paper describes the design of a telemanipulation setup to be used in minimally invasive surgery. Measures of performance and stability are introduced, based on the hybrid matrix of the teleoperator and scattering operator. Both the master and slave device are controlled separately, using damped force control for the master and shared compliance control for the slave. These devices are coupled with the position-error-based force reflection algorithm, where only position signals are used. The performance of this system is acceptable for a reverse force scaling factor smaller than 1, but the input impedance felt by the operator should be lower in order to increase the natural feeling of the environment by the operator. Increasing the force scaling will undo the passivity of the system and can cause instability problems. Using the scattering operator a passivity region is derived within which velocity- and force-scaling factors have to be chosen. Furthermore, some other aspects of the TeleMIS project are described.