Research And Development Of Motion Control System For Micro V-groove Ultra-precision Machining

Machine tool numerical control system used for machining of micro V groove optical fiber connector was developed using ultra precision machining technology and combining with the characteristics of open CNC system. With the popularization of the open architecture controller and ultra-precision processing technology mature gradually, the study of open special machine tool numerical control system has gradually get the favor of manufacturing research and development personnel. In addition, the optical signal in long transmission loss problems also brought to the birth of the special machine tool used for machining of micro V groove optical fiber connector.On Windows platforms, this topic is studied to the IPC with PMAC Motion Controller as the core of the control system using Qt tool to design and development. In this paper, Firstly, researched current for the V groove processing method, the trend of open numerical control system and ultra precision machining technology level and development at home and abroad and expounds the ultra-precision machining of micro V groove of the importance of optical fiber connector.Secondly, through the analysis of the technological parameters of micro V-groove and machining process and machining accuracy required,the paper designed the whole closed loop control system hardware platform. Combining with features and functions of the motion control card, driver, linear motor and grating ruler, configured parameters correctly, and set up the experimental platform, and realized the full closed loop control through the PC software with the software of hardware equipment.Then this paper has developed a special type of man-machine interface operation control based on Clipper controller using Qt development tools. On the PC software, completed the parameters for the G code programming, G code detection, run, stop, pause and other basic operations. Also used PLC program to realize the manual increment of motor feed, absolute feed, inching operation. Finally, also used OPENGL library to realize the basic movement of the machine tool and cutting simulation on the PC interface.Next, the paper analyzed the PID+velocity/acceleration feed forward+NOTCH filter control loop algorithm with PMAC. Through understanding the significance of PID parameters and the impact on system performance, used PMAC PID manual setting function to reduce the following error and enhance the stability of the system and finally, got a very good step response and the dynamic response characteristic curve.Finally, under the condition of getting better PID parameters, used a laser interferometer to set up a platform test. Through own test program, the motor running back and forth all done the positioning accuracy of the test. In order to further improve the precision, the positioning error value was measured by the experiment and found the target location compensation point in the motor running. Then compensated motor movement many times, and compared and analyzed the compensation results before and after, and got better experimental results.