A New Error Compensation Method for Certain Measurement System Using the Change of Position and Pose of Corresponding Image Points

Based on motion error can be reflected by position and pose change, a new error compensation method using position and pose change of corresponding image points to establish the error compensation model for certain measurement system is proposed. Firstly we observe at position 1, actively and quantificationally change to position 2 by the motion controller controls, combining with exterior orientation elements at position 1, the initial value of exterior orientation elements at position 2 can be obtained by coordinate conversion principle. Subsequently the coordinate values of fitting pixel in checkerboard calibration plate's corner points can be obtained by using collinear equation as well.Then, we observe at position 2, and establish the error equation by differentiating the observed values from the corresponding fitting one, herein motion error corrected values can be solved iteratively. Finally we can establish the error compensation model by nonlinear least square fitting of multiple sets of error data of each motion axis. The experimental results show that: The proposed method can compensate for system motion errors without involved in professional instrument, and it has the advantages of easy operation and low cost. Besides, the compensation model needs fewer parameters, the error can be reduced to sub-millimeter scale after compensation.