Design of a 4-DOF forceps manipulator for robotic surgery

In this paper, mechanical design of a forceps manipulator for minimally invasive surgery is discussed. The discussed forceps manipulator has 4-DOF link mechanism inside the abdominal cavity so that pivoting motion around the insertion point is not required. The 4-DOF forceps consists of serially-connected two flexible joints to reduce the number of mechanical parts such as pins. The length of flexible joints is designed so that it covers the desired workspace. Workspace of forceps with several link parameters are calculated using the Monte Carlo method. The configuration which achieves the broadest workspace is selected according to the calculation results.