A Vibration-Compensated Continuum Manipulator Drill System for Orthopaedic Surgery

Continuum manipulators have shown great promise when applied toward minimally invasive orthopaedic surgery. The enhanced dexterity of continuum manipulators allows for controlled drilling and milling of curved tunnels and pockets within bone, providing a workspace advantage against conventional straight drills or revolute-jointed manipulators. However, the enhanced compliance that allows this class of manipulators to excel also renders them susceptible to chatter during milling or debriding operations. To counteract these vibrations and enable faster, more extensive surgical operations, we present a robotic, continuum manipulator-equipped drill system designed with high-bandwidth cable tension control. Through phantom and cadaver experiments, the design process, system identification, performance characteristics, and clinical relevance of the system are validated. Material removal rates of up to 1700 mm³/s are achieved and bone-simulating foams of densities up to 50 per cubic foot (PCF) are successfully milled. The outcomes of these experiments substantiate the use of high-bandwidth actuation as a solution for suppressing cutting vibrations with continuum manipulators, promoting patient safety, minimizing healthy-tissue loss, and increasing reachable workspace across the domain of orthopaedic surgery.