基于PLC技术的机电一体化数控机床运行控制研究

Research on Operation Control of Electromechanical Integrated CNC Machine Tool Based on PLC Technology

针对传统机电数控机床运行控制效果不佳,导致加工精度较低的问题,提出基于误差补偿技术和ARM平台,构建一个基于PLC技术的综合误差实时补偿系统。首先,分别对数控机床温度和机床参数进行采集和存储;然后通过训练的BP神经网络进行误差计算,以建立机床-几何-热切削力的综合误差模型;最后利用误差补偿方法计算当前时刻误差补偿值,并发送至机床PLC实现误差实时补偿。实验表明,通过本系统可直观监测机床加工状态,实现误差补偿参数设置。QLM27100型机床测试中,曲面1的最大误差和平均误差分别为84.6μm和39.74μm;曲面2的最大误差和平均误差分别为52.81μm和13.17μm,对比于曲面1,曲面2的误差更小,测量精度更高。由此可知,本系统在机床加工中可减小误差,提升加工精度,实现机电一体化和智能化控制。

In view of the poor operation control effect and low machining accuracy,a comprehensive real-time error compensation system based on PLC technology is constructed based on error compensation technology and ARM platform.Firstly,the CNC machine tool temperature and machine tool parameters are collected and stored respectively;then the trained BP neural network is calculated to establish the comprehensive error model of machine tool-geometry-thermal cutting force.Finally,the error compensation method is used to calculate the current moment error compensation value and sent to the machine tool PLC to realize real-time error compensation.The experiment shows that the system can monitor the machining state and set the error compensation parameter.In the QLM27100 machine tool test,the maximum and average errors of surface 1 are 84.6μm and 39.74μm,respectively;the maximum and average errors of surface 2 are 52.81μm and 13.17μm,respectively,and the surface 2 has less error and higher measurement accuracy than the surface 1.Therefore,the system can reduce the error,improve the machining accuracy,and realize the mechatronics and intelligent control.