Kinematics Modeling and Trajectory Planning for the Skull Reconstruction Robot

Abstract

A skull reconstruction robot has been developed to effectively overcome shortcomings of the traditional skull surgery and improve its efficiency and quality. In this study, kinematics modeling and trajectory planning for the robot are carried out. Firstly, the kinematic model of the robot is established based on the D-H method. The positioning points, which are used to determine the cutting plane, are given on the surface of the skull by the surgeon. The contour data for cutting can be obtained using a two dimensional laser scanning sensor, by adjusting the scanning light curtain to coincide with the cutting plane. Then, to ensure that the tools fixed at the robot end can always be perpendicular to the skull surface during the cutting or drawing process, the principal component analysis is introduced to design the normal vectors at the selected key points of the point cloud data for the skull surface. Moreover, the quintic polynomial interpolation method is used to construct the curves between the adjacent key points to make up for the defects of the skull surface and ensure the smoothness of the trajectory. Finally, workspace analysis based on Monte Carlo method is implemented, and the proposed kinematics modeling and trajectory planning methods are validated by simulation.