Conceptual design of force reflection control for teleoperated bone surgery

Abstract

Bilateral control of teleoperated robots still poses a challenge, especially if environment properties vary over a large degree. Most currently available systems do not provide force feedback and consequently surgeons still have to estimate contact forces predominantly visually. During drilling or milling in bone surgery, visual estimation is virtually impossible due to hardly any deformations. However, the force progression contains important complimentary information for the surgeon. Therefore, a concept for a force-reflecting controller for drilling or milling during teleoperated bone surgery was developed and tested on a one degree of freedom (DOF) test setup. First, the desired behavior and control architectures were derived based on the context of bone surgery. The resulting controller combines three control architectures in a switching controller, depending on the tool actuation and environment properties. Experimental results with a 1-DOF test setup showed the desired control and switching behavior, while remaining stable. Therefore, the developed control concept seems promising for teleoperated bone surgery.