Calibration method of robot base frame using procrustes analysis

A novel effective robot base frame calibration method using Procrustes Analysis is presented. The errors from the design, manufacture and assembly of robot in the mechanism cause the deviation of nominal base frame used by the robot controller and the actual mechanical base frame. The actual mechanical base frame can be established by external precision measurement. The theory of Procrustes Analysis is introduced into the analysis of the relation of the two base frames. In order to make sure the rotation matrix is orthonormal and normalized, an optimal estimation of the relative rotation between the two base frames is solved out under the criterion of optimal Frobenius norm approximation. Meanwhile, by the Lagrange Multiplier method and Singular Value Decomposition (SVD), an orthonormal rotation matrix can be reached. Finally, experiments on a 6-DOF industrial robot researched and developed independently are performed with FARO ARM to demonstrate the superiority of the proposed method. Using this method, the relation of the two base frames is obtained, and it makes the motion planning possible. The calibration method is useful to other problem that formulated in the same mathematical form, such as multirobot coordination and robot hand-eye system calibration.