基于多体理论模型的加工中心热误差补偿技术

MULTI-BODY SYSTEM-BASED TECHNIQUE FOR COMPENSATING THERMAL ERRORS IN MACHINING CENTERS

基于多体系统理论，建立了数控加工中心热误差模型，并提出其误差补偿方法。以三坐标ＭＡＫＩＮＯ加工中心为例，建立了具体模型并进行参数辨识。优选了４个测温点，实时测量其温度，作为误差参数辨识模型的输入值，实现了软件实时补偿。在该加工中心上分别沿３个坐标方向加工一系列表面并比较加入热误差补偿的结果，测量结果表明补偿效果显著。实践说明所建热误差模型的有效性和补偿方法的可行性。

Based on MBS (Multi-body system), an error model is presented here for the thermal errors in machining centers as well as the related compensation method. Taking three-axis MAKINO machining center as an example, a specific error model is set up through theoretically analyzing and experimentally parameter-identifying. Four temperature sensors are selected after optimization, and the temperature changes from their readings offered as the inputs to the error parameter models. Then a real-time software compensation is carried out, a set of small surfaces are cut on the machining center along the x, y and z-axis with and without error compensation. The measurement results from CMM show an obvious improvement is obtained after the real-time compensation. Thus the facts above verified the validity and feasibility of this error model and compensation method.