For the total hip replacement surgery using the noncemented prosthesis, it is very important to carve a cavity in a femur that precisely matches the shape of an artificial hip implant because close apposition to the bone cavity is necessary for a bone to grow into the porous surface. In this study a new type robot for total hip replacement surgery is developed. The surgery robot is designed to be fixed directly onto patient’s femur by clamp that is currently used as surgical tool. The parallel-serial type manipulator is designed as a surgical robot. It consists of 3RPS parallel manipulator and additional linear slider. The robot, which has a redundancy, is analyzed with respect to kinematic parameters. Dexterity, actuator force and uniformity are introduced as performance index and then normalized performance index (PI) is used as objective function. The surgical robot is optimized from the viewpoint of PI. The prototype is manufactured and proved to be able to apply at hip replacement surgery.
