Structure Optimization of a Bi-planar Parallel Mechanism for Spine Surgeries

Due to the urgent needs for high precision surgical equipments in minimally invasive spine surgeries, a novel robot-assisted system for the accurate placement of pedicle screws in lumbar spinal surgeries is developed. The structure design of the robot is based on a macro-micro mechanism, which includes a serial mechanism and a bi-planar 5R parallel mechanism. The researchable workspace, kinematic model and dynamic model of the planar 5R mechanism are analyzed, based on which the links lengths of 5R mechanisms are optimized. This paper provides a reference for the structure design of new medical robots for minimally invasive spine surgeries.