A Subject-Specific Four-Degree-of-Freedom Foot Interface to Control a Surgical Robot

This article introduces a passive four-degree-of-freedom foot interface to control a robotic surgical instrument. This interface is based on a parallel-serial hybrid mechanism with springs and force sensors. In contrast to existing switch-based interfaces that can command a slave robot arm at constant speed in only discrete directions, the novel interface provides an operator with intuitive control in continuous directions and speed with force and position feedback. The output command of the interface was initially derived based on the kinematics and statics of the interface. Since distinct movement patterns among different subjects were observed in a pilot test, a data-driven approach using independent component analysis was developed to convert the foot inputs to the control commands of the user. The capability of this interface in controlling a robotic arm in multiple degrees of freedom was further verified with a teleoperation test.