A New Type of Planar Two Degree-of-Freedom Remote Center-of-Motion Mechanism Inspired by the Peaucellier–Lipkin Straight-Line Linkage

Abstract

Benefiting from small incisions, reduced risk of infection, less pain, and fast recovery, minimally invasive surgery has shown tremendous advantages for patients. In these kinds of procedures, remote center-of-motion (RCM) mechanisms play an important role in performing operations through small incisions. Inspired by the Peaucellier–Lipkin straight-line cell, this paper presents the design and verification of a new type of planar two degree-of-freedom (DOF) RCM mechanism. A synthesized planar RCM mechanism is realized by a symmetric linkage actuated by two circular motion generators. The main merit of the proposed 2DOF RCM mechanism is its straightforward kinematics, which results in a simple control scheme. One of the candidate mechanisms, which is simple in structure and easy to fabricate, is intensively investigated. A prototype was built, on which preliminary experiments have been conducted, to verify the feasibility of the proposed new mechanism. The experimental results show that the fabricated 2DOF prototype has a nearly stationary remote center of motion. Therefore, the prototype has potential applicability in robot-assisted minimally invasive surgeries.