A virtual educational model on a CNC milling machine including and excluding two methods of fuzzy controllers

Purpose Training centers and labs offer many applications suitable for beginners who want to know how to set and operate a computer numerical control (CNC) milling machine. However, few applications address a basic understanding of the machining process founded on mathematical principals in line with new high-speed and high-precision machining technologies. The purpose of this paper is to present a complex mechanism in a simplified way, explaining the subject at an elementary level. Design/methodology/approach The authors have developed an application of the CNC milling machine in a Matlab/Simulink package, obtaining the appropriate parameters mathematically. The project developed an analytical method using Matlab code to test the step response (the actual cutting force) under various parameters to ensure comparability of the designed model. The analytical results are in line with the developed model. The Matlab/Simulink user interface allows the application to better explain machining for educational purposes. Furthermore, by combining this mathematical model and the fuzzy controller, the high-speed constant-force milling control model has a user interface for data entry. The addition of two kinds of fuzzy controllers (look-up table and Mamdani) achieve a more educational environment compared with existing models. Findings The developed technique can be used in CNC milling machine centers and laboratories. For virtual training purposes, this paper provides a two-stage educational model, giving students the necessary feedback on what they have learned at each stage from the beginning use of the CNC milling machine, with and without the controller. The system also offers to track the step-response analysis method. This method overcomes the shortage of milling processes modeled by the traditional transfer function, which more accurately establishes the relationship between cutting force and cutting parameters. Practical implications This technique can be used in the CNC machine centers and laboratory for teaching beginner students and trainees. Real data from the workshop had been used. Originality/value The earlier versions of this manuscript were presented in: JVE International LTD. Vibroengineering Procedia. +2017. 14.; IEEE 4th International Conference on Information Science and Control Engineering (ICISCE) +2017.

Error Sensitivity Analysis of a Novel A/B Bi-Rotary Head

A novel A/B bi-rotary head is designed which can be used on five-axis machine centers. The motion of pitching and swing can be achieved by controlling the output angle and velocity of motors. Anti-backlash control method can be applied to eliminate the transmission backlash. The error sensitivity model is also established using matrix differential method, and the influence of internal errors on the integrated errors is obtained. The results show that the more sensitive errors can be identified from all errors which need to be controlled rationally.

Test and Analysis of Machine Center's Principal Spindle Dynamic Errors

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