激光多普勒技术与直线度测量

Laser Doppler Technique and Straightness Measurements

在三坐标测量机（ＣＭＭ）及精密加工机床等设备的高精度测量中，主轴及导轨的直线度、水平或竖直偏摆角的测量是相当重要的。在过去，这类机器的直线度的测量，大部实现起来比较困难，或者精度很低且费时。这里我们将介绍一种直线度测量的新方法，采用双光束系统的激光多普勒测量仪（简称ＬＤＤＭ），通过测量每一点的偏摆角，并按一定的准则计算出直线度。下面将分别简述有关的原理、精度及与其它测量方法相比较的优越性．由于这种测量技术可以对位移和角度进行同时测量，使得直线度实现了在线测量，这就为三维坐标测量仪器的精度拟合及代替线性编码器进行位置和直线性的标定提供了简易高效的新方法．

The measurements of straightness of main shaft and guide, andhorizontal and vertical deviation angle are very important for the highprecision measurement of 3-coordinate measurement machines (CMM) theprecision machine tools. The straightness measurements of such machinesused to be difficult to realize,or with low accuracy and time-costing.A newme thod for straightness measure ment, using a double-beam Laser Dopplermeter (LDDM),is introduced here .By measuring the deviation angle of eachpoint, the straightness can be calculated according to some criterions. Theprinciples, accuracy and its advantages to other methods are briefly described .Since the displacement and angle can be measured simultaneously, thistechniqUe are very suitable for on-line measure ments,supplying a simple andefficient method for 3-dimensional accuracy fitting, and it can substitutefor the lienear encoder during the position and straightness calibration of3-dimensional measurement instruments.