基于测距传感器的WMPS非接触测量方法

Non-contact measurement method of WMPS based on laser ranging sensors

为了解决现有的工作空间测量定位系统(WMPS)中柔性待测物表面形变及大尺寸测量空间内遮挡等问题,提出了一种基于测距传感器的非接触测量方法,并设计了基于该方法的测量靶。首先建立了该方法的测量模型,将测量靶抽象为若干个控制点和一个矢量;然后通过发射站的数学模型推导出了测量靶姿态迭代解算方法,并通过单位四元数估计法给出了该迭代算法的初值生成方法;最后采用自标定方法对测量靶进行了参量标定,并依托天津大学研制的WMPS系统进行了精度验证实验。结果表明,该测量靶的重复性测量精度为1mm,距离测量精度为2.5mm。该方法使得WMPS系统的测量范围扩大并保持了较高的空间3维坐标测量精度。

Workshop measuring and positioning system （WMPS） may induce distortion of flexible object surface and thereare hidden parts in large-scale space. In order to solve the problems, non-contact measurement method was proposed based onlaser rangefinders. A measurement target was designed. Firstly, a measurement model of this method was established, and thetarget was simplified as the combination of several control points and a vector. Then, an attitude estimation algorithm wasdeduced from the geometry model of the transmitter, and the initial iteration value was estimated through unit quaternion method.Finally, calibration experiment of the target was conducted and the accuracy of the method was verified on a WMPS experimentalplatform developed by Tianjin University. The experimental results show that, distance measurement accuracy of the proposedmethod is better than 2. 5mm and repeatability keeps within 1 mm. This measurement method can extend the range ofmeasurement and maintain relatively high accuracy of large-scale 3-D coordinate measurement.