Toward Clinically Applicable Steady-Hand Eye Robot for Vitreoretinal Surgery

Abstract

This paper reports new developments and optimizations for clinical use of the Steady-Hand Eye Robot for vitreoretinal surgery. Vitreoretinal surgery requires precise micro-manipulation of delicate tissues. Surgical performance is limited by physiological hand tremor, fatigue, poor kinesthetic feedback, as well as patient movement. The previously developed Steady-Hand Eye Robot has been extensively used in in vivo experiments. Several safety and ergonomic limitations observed in the in vivo environment serve as motivation for a novel robot wrist design. The new robot wrist consists of a symmetric remote center of motion (RCM) tilt mechanism and a slim tool holder with a quick release mechanism for the surgical instruments. The RCM tilt mechanism provides a tilt motion range of ±45° and a stiffness of 21 N/mm. Two different release force thresholds for the quick release mechanism were designed. The soft configuration requires 2–3 N to retract the surgical instruments while the hard configuration requires 5–6 N.