Development of a six degree of freedom (DOF) hybrid robot for femur shaft fracture reduction

When doing femur fracture reduction surgery, both patient and surgeon are exposed to a great amount of radiation, which is harmful to their health. Computer assisted orthopaedic surgery (CAOS) is a less invasive approach for its ability to reduce the usage of image intensifier. Various robots have been developed for femur fracture reduction surgery. Most of these robots are beared on serial architecture. The low transportable load and poor accuracy are both inherent in serial robots, which makes them inappropriate for femur fracture reduction. Some fully parallel robots using the ldquoStewart platformrdquo are also developed for femur fracture reduction, but their restricted workspace limits their performance. To balance the accuracy and workspace, a new hybrid robot with six degree-of-freedom is reported here. It possesses the characteristic of the Cartesian coordinate robot, all the movement of the actuators are linear, which makes its movement smooth for low speed fracture reduction procedure.