<title>Development of a new high-dexterity manipulator for robot-assisted microsurgery</title>

Abstract

We are developing a new robotic system applicable to micro- and minimally invasive surgeries. The goal is a dexterity-enhancing master-slave that will refine the scale of current microsurgeries, and minimize effects of involuntary tremor and jerk in surgeons' hands. As a result, new procedures of the eye, ear, brain and other critical faculties will become possible, and the positive outcome rates in conventional procedures will improve. In nominal configuration, this new robot assisted microsurgery (RAMS) system has a surgeon's hand controller immediately adjacent to the robot. The RAMS system is also potentially applicable to `telesurgery' -- surgeries to be carried out in local-remote settings and time-delayed operating theaters -- as considered important in field emergencies and displaced expertise scenarios. As of August 1994 we have developed and demonstrated a new 6 degree-of- freedom robot (slave) for the RAMS system. The robot and its associated Cartesian controls enable relative positioning of surgical tools to approximately 25 microns within a non-indexed and singularity-free work volume of approximately 20 cubic centimeters. This implies the capability to down-scale hand motion inputs by two to three times, and the consequent performance of delicate procedures in such areas as vitreo-retinal surgery, for which clinical trials of this robot are planned in 1996. Further, by virtue of an innovative drive actuation, the robot can sustain full extent loads up to three pounds, making it applicable to both fine manipulation of microsurgical tools and also the dexterous handling of larger powered devices of minimally invasive surgery. In this paper, we overview the robot mechanical design, controls implementation, and our preliminary experimentation with same. Our accompanying oral presentation includes a five minute video tape display of some engineering laboratory results achieved to date.