Research On CNC System Of Precision5-axis Micro-milling Machine Tool Based On IMAC

Nowadays miniature parts and micro structures are widely used in civil and military field, e.g., aerospace technology, biomedical technology, information technology etal. Micro milling has advantages in the manufacture of three-dimensional (3D) micro structures and free-form surfaces. Therefore micro milling has become a research focus in mechanical manufacturing. Micro milling machine tool is a fundamental factor affecting the quality of micro structures. As the control center for the movement of machine tool, the performance of computer numerical control (CNC) system is crucial for the machining accuracy of the micro milling. Consequently it is significant to research on the CNC system of the micro milling machine tool.In this thesis, the related parameters and online command of IMAC (Industrial Motion and Automation Control) are analyzed. Using trial and error method, position step and parabolic velocity response are adopted to adjust and optimize the servo control parameters, so as to improve the response performance and reduce the following error of the motor.The communication between IMAC and industrial computer is built through the function library of PcommSever. According the planned function modules, the CNC software is developed in Visual C++. The CNC software contains main interface, menu, rotary buffer interface, system setting, cutter setting by CCD and CNC simulation by VERICUT.The original positioning error is measured by t he single-frequency laser interferometer (ML10) produced by Renishaw. Analyzing and calculating the measured data, the compensation values are obtained to adjust the positioning error of the linear motors. The original positioning error of the motor for X axis is±5μ.m and the backlash is8μm. While after compensated, the final positioning error is±0.3μm without backlash.Considering the influence factor of the tool path and the profile characters, tool paths for the concave spherical surface, cosine rotary surface and micro lens array are planned. Micro milling experiments for the three micro structures are conducted to verify the servo system adjustment, positioning error compensation and CNC software. The machined micro structures are measured by super depth of field microscope and profilometer. The three micro structures are obtained with high surface quality. The lowest roughness (Ra) of micro lens is0.0754μm. Furthermore, the micro lens array has imaging ability. Hence the CNC system for micro milling has good machining performance.According to the micro milling experiments and measurement results, reliability, human-computer interaction and machining performance of the CNC system are verified. The work conducted in this thesis provides important reference value for research on micro milling CNC system.