Spatial Errors' Measurement And Compensation For The Miller Machine Tool

The CNC machining accuracy , which is one of the most important performance for the machine tools, can be improved by adding the errors' parameters to the errors' compensation model. Measuring the CNC machine tool's geometric errors, establishing the suitable errors' compensation model, applying the proper compensation strategy, are the keys to achieve the machine tool compensation. This paper details the mainly problems on the research of the compensation technology both at home and abroad. The research includes many aspects, such as the reasons for the errors, the measurement of the errors, the construction of the compensation model. This paper can be helpful to the future use.Based on a certain type of CNC machine tool, we use the optical measuring technology to get the precise data. Using the Matlab software to deal with the measuring data, we construct the least-squares-fit straight lines and the polynomial fitting curves , and the error parameters can be finally calculated. After the error examination and error parameters' calculation completed, this paper also refers to the error compensation model for the numerical control machine tools. Processing the data from the DXF file which is exported by the AutoCAD software, is apt to use for compensation. The VB6.0 software is used to complete the error's compensational software's establishment. At last, we design a test to the compensation. The steps according to this paper are as following:Firstly, this paper apply the optical-space-straightness measurement to measure the geometrical error parameters (especially the dX and dY). We use the Matlab software to deal with the measure data, including construct the least-squares fitting straight lines and the polynomial fitting curves. Eventually, based on the error parameters, we abstain error table based on dX and dY (on the XOY plane).Secondly, based on the multi-body system kinematics theory, thinking of the study of the physical structure and the movement of the machine tool, neglected some of the smaller impacts on the machining parts, we establish a mathematical model both with and without the errors of the mathematical model when it moves.Thirdly, looking thought the development of the errors' compensation method, combining the structure of the machine, using the appropriate compensational strategies, we apply the method which is based on the CAD export file (DXF file). Then we get NC codes based on this two types of CAD model generation. The VB6.0 software is used to complete the error's compensational software's establishment. This employment gets a better machining accuracy without making any alternation of the component part for the machine tools.Finally, according to the establishment of error compensation model, two models with and without errors' compensation are evaluated.