An Intelligent Thermal Error Compensation System for CNC Machining Centers
摘要
A measurement and compensation control system for the spindle thermal expansion of machine tools has been developed in this study. The low cost but accurate thermal sensor of AD 590 IC and the tool setting probe MP4 of Renishaw Co. were developed for the measurements of temperature and spindle expansion respectively. Instead of the non-cutting condition as specified by the ISO230-3, the proposed thermal error model is derived from the real cutting condition. With the proper selection of sensor locations, a linear error model with respect to only one or two temperature terms could always be single board computer was then developed to compensate for the thermal error in real time. As the error model can be generated in one day under hazard conditions and the whole system is low cost, this system is suitable for industrial use. The intelligent features of this system include: fast model generation, self-malfunction detection, real-time temperature display, EMI removal, automatic compensation, and suitable for most ambient conditions. Experimental tests show the thermal error of a general type CNC machining center can be controlled to within 10µm.