Ma Xiaofan, Cai Zhiqin, Yao Bin, Cai Sijie, Lu Jie
Appl Opt. 2020 Nov 20;59(33):10626-10637. doi: 10.1364/AO.405554.
Laser triangulation method is widely used in online precision measurement owing to its advantages of being fast, accurate, and dynamic, and having large-scale measurement capability. To improve the accuracy of laser triangulation, the scan depth, inclination angle, rotation angle, and deflection angle are defined. Then, a spatial pose error model and an experimental model for laser measurement error are established. Next, error analysis experiments are conducted, and the influence of spatial pose parameters on the error is analyzed. Further, error proofreading experiments on the surface characteristics of the measured workpiece, including the material, surface roughness, and color, are completed, and their influences on the error are analyzed. Based on the experimental data, an error correction model based on support vector regression is established. Measurement strategies are formulated considering multi-factor constraints such as optical path interference, mechanical interference, scan depth of field, measurement angle, and measurement path. The tooth profile of a cycloid gear is taken as the measurement object, then the measurement path planning is performed, and the error correction model is used to correct the measured data. The accuracy of the results agrees well with the result of a fully automatic computer numerical control (CNC)-controlled P 65 precision measuring center.
激光三角测量法因其具有快速、准确、动态以及具备大规模测量能力等优点，而被广泛应用于在线精密测量中。为提高激光三角测量的精度，定义了扫描深度、倾斜角、旋转角和偏转角。然后，建立了空间位姿误差模型和激光测量误差实验模型。接下来，进行误差分析实验，并分析空间位姿参数对误差的影响。进一步地，完成了对被测工件表面特性（包括材料、表面粗糙度和颜色）的误差校正实验，并分析了它们对误差的影响。基于实验数据，建立了基于支持向量回归的误差校正模型。考虑光程干涉、机械干涉、扫描景深、测量角度和测量路径等多因素约束，制定了测量策略。以摆线齿轮的齿廓为测量对象，进行测量路径规划，并使用误差校正模型对测量数据进行校正。结果的精度与全自动计算机数控（CNC）控制的P 65精密测量中心的结果吻合良好。
