基于PSD的腔体相对位移测量方法设计

A Relative Movement Measurement Method Design of Cavity Based on PSD

为了测量只能在侧壁安装检测装置的腔体间相对位移,设计了基于面光源的光位移传感器(PSD)位移测量系统。系统将PSD两路电信号的I-V转换、反向放大等信号调理在一片AD824处理,并采用对射式的检测方法,减小了系统体积,简化了结构设计。介绍了位移测量实现过程,并设计系统的标定工装,通过数据后处理方法减小测量误差,提高测量精度。实验结果表明,系统在30 mm量程范围内线性度好,可重复性高,工作在10 kHz不失真,可用于腔体振动等测量,具有很高的实用性。

The measurement of relative movement makes it difficult to settle the detector on objective structure. For the special cavity structure that the detector could only settle on its broadside, a correlative measurement cfircuit was designed based on PSD （Position Sensitive Detector）. The I-V conversion, reverse amplification and other signal conditioning methods are processed on a single AD824. The opposite-type detection method reduces the physical size and simplifies the structural design.. The source and sensor are installed out of the cavity, so kinematic interference is avoided. A simple light source design can get high measurement precision, and also make it feasibility. Movement measuring process was introduced in detail, and the calibration fixture is designed for the system. Measurement errors were minimized through data post-processing method which could improve the accuracy of measurement. Experiments show that the system has high repeatability and fast response within 30 mm ranges, which can be applied to relative movement measurement system in similar structures