Modeling, Design, Identification of D-H Parameters and Calibration of Surgical Coordinate Measuring Mechanism

A portable Surgical Coordinate Measuring Mechanism (SCMM) is designed and developed to measure the 3D coordinates of a point and a line vector passing through a point in its workspace. The synthesis of the mechanism is done to localize a neuro-anatomical reference frame with respect to the robot reference coordinate system. The SCMM is an articulated serial chain and is an important constituent of the neurosurgical suite being developed by DRHR, BARC, Mumbai. Dimensional synthesis of the SCMM is carried out by optimizing the mechanism footprint and manipulability of the neuro-registration. Design, development, calibration, and demonstration of SCMM are discussed in the paper. The paper emphasizes that the measured values of the D-H parameters are most often not practically feasible for implementation. It is shown that calibration-based methods are useful for improving the accuracy of system.