Hybrid Control for Remote Surgery Subject to Time Delay

Through the use of telerobotics, surgeons can perform operations on patients from a distance, via a communication network. However, a major issue to these procedures is the existence and effect of time delays, which are known to negatively affect performance. In addition, the forces that occur due to tool-tissue interaction may also present problems during operations. This paper investigates and compares the use of Proportional-Integral-Derivative (PID) controllers and Model Predictive Controllers (MPCs) used in hybrid control, and their effects on the performance of the da Vinci™Patient Side Manipulator (PSM), a surgical robot, when subjected to different time delays. It was found that hybrid MPCs have better trajectory control, however hybrid PID controllers exhibit greater ability to adapt to undesirable external forces from contact. Further research into implementing a predictor with the PID controllers and comparing results, as well as integrating benefits of both controllers into a single hybrid control would provide great benefits for improving surgical telerobotic performance.