Thermal Error Modeling of a Horizontal Machining Center Using the Fuzzy Logic Strategy

퍼지논리를 이용한 수평 머시닝 센터의 열변형 오차 모델링

  • 이재하 (경북대학교 대학원 기계공학부) ;
  • 이진현 (안동정보대 기계과) ;
  • 양승한 (경북대학교 기계공학부)
  • Published : 2000.10.01


As current manufacturing processes require high spindle speed and precise machining, increasing accuracy by reducing volumetric errors of the machine itself, particularly thermal errors, is very important. Thermal errors can be estimated by many empirical models, for example, an FEM model, a neural network model, a linear regression model, an engineering judgment model, etc. This paper discusses to make a modeling of thermal errors efficiently through backward elimination and fuzzy logic strategy. The model of a thermal error using fuzzy logic strategy overcomes limitation of accuracy in the linear regression model or the engineering judgment model. It shows that the fuzzy model has more better performance than linear regression model, though it has less number of thermal variables than the other. The fuzzy model does not need to have complex procedure such like multi-regression and to know the characteristics of the plant, and the parameters of the model can be mathematically calculated. Also, the fuzzy model can be applied to any machine, but it delivers greater accuracy and robustness.


Fuzzy Logic Model;Thermal Errors;Linear Regression Model;Engineering Judgment Model;Backward Elimination


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