The identification method of the relative position relationship between the rotary and linear axis of multi-axis numerical control machine tool by laser tracker

In the multi-axis machining process, the relative position relationship between the linear and rotary axis also has certain influence on the machining accuracy in addition to 6 geometric errors of each axis. How to accurately detect and compensate for this error will have a positive effect on further improving the machining of multi-axis machine tool. The laser tracker is adopted multi-station and time-sharing measurement to identify the relative position relationship between the rotary and linear axis on the basis of global positioning system principle in this paper, which will provide data support for accuracy compensation for multi-axis machine tool. The relative position relationship between the rotary and linear axis is characterized by the homogeneous transformation matrix, and its influence on the motion accuracy of machine tool is also analyzed. Meanwhile, the mathematical model concerning on identifying the relative position relationship between the rotary and linear axis with laser tracker is established, and the corresponding measurement algorithm of machine tool motion and identification algorithm of the relative position relationship are derived respectively. The feasibility and accuracy of the derived algorithms are demonstrated in simulations. Meanwhile, the experiment further validates the feasibility of the proposed method. (C) 2018 Elsevier Ltd. All rights reserved.