基于虚拟仪器的轴类零件弯曲变形在线测控系统

On-line Measurement and Control System for Shaft Parts Bend and Distortion Based on Virtual Instrument

研究系统软硬件组成、通讯及编程,轴的测量原理的确定。系统采用PC机为上位机,PLC与控制器为下位机的主从结构,通讯方式用RS232串口通讯,软件用VB与VC混合编程实现虚拟测控界面、数据的实时采集及控制。通过测量较少的轴截面,用最小二乘法求轴截面轴心点,将离散的轴心点拟合成轴心曲线,再用数值解法求最大曲率及位置,准确判断最大弯曲变形的位置。实验结果表明,系统人机界面良好,操作与控制方便,操作者可直接观察到测量与控制数据。所用测量原理满足要求。

The thesis researches on the software and hardware composi tion, communication and program as well as the shaft measurement principle confi rmation of the on-line measurement system. The system adapts the master slave co mputer structure with PC as the epigenous computer and PLC and controller as the hypogenous computer. The communicating mode uses the RS232 serial communication and the software adapts the mixing program of VB and VC in order to realize the virtual measurement and control interface and the real-time collection and cont rol of data. Through measuring the fewer shaft section, using the minimal binary multiplication seeks the central point of the shaft section and the discrete sh aft center points are composed into a curve of shaft central point. And then usi ng the numeric approach calculates the maximum curvature and location. Then exac tly estimate the site of maximum bend and distortion at last. The result shows t hat the system man-machine interface is well, the control and operation is conve nient, as well as the operator may straightly observe the control and measuremen t data. So the measurement principle satisfies the demands.