Compliant Remote Center Motion Mechanism for Minimally Invasive Surgical Robots

A high precision or surgeon skills are required in some of the precision procedures such as micro-scale minimally invasive surgeries. Robotic manipulators are being explored for carrying out surgeries with minimal invasion, outstanding precision and stability of the tool. Major challenges in developing such systems are motion of the tool with "mechanical" remote center and preserving surgical feel of the surgeon. This paper presents conceptual design of 2-DOF isosceles trapezoidal remote center motion mechanism. The proposed concepts use mechanically generated RCM. The compact and handy design helps to preserve the 'surgical feel'. The use of compliant links over rigid link mechanism brings the precision in manipulation. Extensive, nonlinear FE analysis demonstrates the accuracy of the RCM. Further the actuation method, sensor scheme and control scheme are presented as an example case.