A New 3R1T Parallel Robot with Remote Centre of Motion for Minimally Invasive Surgery

This paper describes the design and development of a new 3R1T parallel medical robot for minimally invasive surgery. This is the first time a coaxial spherical parallel mechanism has been utilised in a surgical capacity, integrating a cable-driven translational fourth degree of freedom. The forward and inverse kinematics, workspace and singularity analyses, cable motion range and dimensional synthesis are presented. The detailed mechanical design is discussed, including a novel method for translating the surgical tool via a cable driven actuation system. As all the motors have been successfully located on the base, inertial forces are reduced. The physical prototype of the robot has been fabricated.