The use of thermal imaging, temperature and distortion models for machine tool thermal error reduction

Research has shown that up to 75 per cent of the total machining error can be produced by thermal distortion. Thermal error compensation can provide a n attractive solution to this accuracy problem. Research has shown that the rmal error compensation can reduce thermal errors to an acceptable level, b ut the techniques adopted have had inherent disadvantages that make them im practical for general use. This paper describes a novel indirect measuremen t based thermal error compensation technique that overcomes the main diffic ulties of applying thermal compensation, making it practical and generally applicable. The technique makes extensive use of thermal imaging for rapid assessment of machine tool thermal behaviour and off-line development of th e compensation models. To illustrate the use of the technique it is applied to the head slide of a vertical machining centre.