Chen Lei, Zhang Dengwei, Zhou Yilan, Liu Cheng, Che Shuangliang
Zhejiang University, State Key Laboratory of Modern Optical Instrumentation, Hangzhou, Zhejiang, 310027, China.
Sci Rep. 2018 Jun 14;8(1):9094. doi: 10.1038/s41598-018-27410-4.
A wide dynamic range, high precision, non-contact and large bandwidth angular displacement measurement (ADM) is greatly necessary for the applications such as industrial control and military equipment. This paper proposes a simple and effective ADM method based on Doppler Effect, heterodyne detection and diffuse reflection, which can fulfill these requirements simultaneously. Two beams of parallel light generated by a pair of laser Doppler vibrometers are incident upon the surface of rotational target, then data processing unit acquires the velocity of dual laser incident points on the moving target, and resolves the rotational angular displacement and translation displacement of target through the relationship between dual laser beams dynamically. Several major measurement errors that may affect the ADM accuracy are analyzed. A high precision rotary table is used as an angular displacement standard to verify the measurement range and accuracy, the verification experiment shows that the measurement range is not less than ±10° and the measurement accuracy is 0.0362° based on the method. After using a polynomial error compensation, the measurement accuracy can be promoted to 0.0088°, and this compensation method can be applied to real time measurement.
对于工业控制和军事装备等应用而言，宽动态范围、高精度、非接触且大带宽的角位移测量（ADM）极为必要。本文提出了一种基于多普勒效应、外差检测和漫反射的简单有效的ADM方法，该方法能同时满足这些要求。由一对激光多普勒振动计产生的两束平行光入射到旋转目标表面，然后数据处理单元获取移动目标上双激光入射点的速度，并通过双激光束之间的动态关系解析目标的旋转角位移和平移位移。分析了可能影响ADM精度的几个主要测量误差。使用高精度转台作为角位移标准来验证测量范围和精度，验证实验表明基于该方法测量范围不小于±10°，测量精度为0.0362°。采用多项式误差补偿后，测量精度可提高到0.0088°，且这种补偿方法可应用于实时测量。
