Abstract:
The efficient machining of non-circular body of revolution requires a set of feed drive which actuates the tool-frame to make reciprocating motion. An innovative feed drive actuated by the stepper motor is introduced for the purpose. To eliminate quantitative error, the stepper motor is controlled under the continual mode. It is achieved with a micro-controller system and a built-in control algorithm program, called "tracking algorithm". Within each sampling cycle, the micro-controller will sample the input signal and the time interval will be divided into two parts according to the relative position between two adjacent stepping points. The phase coils correspondent to the two adjacent stepping points are energized respectively with calculated time duration. In this way, the motion of the tool frame smoothly tracks the input signal. The theoretical analysis and experimental study of frequency response of the proposed drive are presented. Experimental results show that the bandwidth of the feed drive system exceeds 310 Hz.
Key words:
Feed drive Digital control Frequency response Noncircular cutting
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Selected from Proceedings of International Symposium of Advanced
Manufacturing Technology (ISAMT'2001); revised manuscript August 18, 2002
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