Journal of the Korean Society for Precision Engineering (한국정밀공학회지)

Korean Society for Precision Engineering (한국정밀공학회)
권호 표지

Improvement of Corner Contouring Accuracy of CNC Servo Systems with Communication Delay

통신지연을 갖는 CNC 서보 시스템에 대한 모서리 윤곽정확도 향상

  • Received : 2010.11.04
  • Accepted : 2010.11.22
  • Published : 2011.02.01
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Abstract

Contouring accuracy of CNC machine tools is very important for high-speed and high-precision machining. In particular, large contour error may occur during corner tracking. In order to reduce the corner contouring error, acceleration and deceleration control or tool-path planning methods have been suggested. However, they do not directly control the corner contouring error. In the meantime, network servo systems are widely used because of their easiness of building and cost effectiveness. Communication latency between the master controller and servo drives, however, may deteriorate contouring accuracy especially during corner tracking. This paper proposes a control strategy that can accurately calculate and directly control the corner contouring error. A prediction control is combined with the above control to cope with communication latency. The proposed control method is evaluated through computer simulation and experiments. The results show its validity and usefulness.

Keywords

Acknowledgement

Supported by : 단국대학교

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