Shared Control for a Handheld Orthopedic Surgical Robot

Abstract

A handheld robot with embedded parallel kinematic manipulator (PKM) is of compact size and is able to provide a similar workflow and exhibit great usability in robot-assisted surgery. The handheld robot is particularly advantageous for tremor suppression and motion stabilization, but also suffers from the issues of the actuators reaching the limit of their range of motion and the reflected force artifact from the actuators. These two pitfalls could make the handheld robot produce intermittent pause or jerky force during human operation. In this paper, a shared control with a handle-based navigation human-machine interface (HMI) has been proposed. A guiding pose region was designed to meet both the indices of dexterity maximization and kinetic energy minimization of the PKM. The control of the handheld robot is shared by the human for holding the handle entering the guiding pose region and by the PKM for positioning the tool and eliminating human tremor. The experimental results presented that the handheld robot under shared control with handle-based HMI could achieve an improvement both in tool tracking accuracy and force artifact reduction without intermittent pause than the counterpart which is under cooperative control with the traditional tool-based HMI.