为解决基于位置敏感器件(PSD)的激光三角位移传感器在复杂光电噪声干扰下的精密标定问题,提出一种多元自适应卡尔曼滤波(MAKF)与非均匀B样条曲线拟合的联合标定方法。通过分析测量原理和计算方法,对位移传感器的非线性特性进行了详细说明,进而提出应用曲线拟合的方法进行非线性标定。针对曲线拟合的特点,设计了一种多元自适应卡尔曼预处理算法用于滤除光电噪声干扰;通过非均匀的节点矢量划分,构建了B样条曲线拟合模型,进一步提高了标定系统的精度。在实际工况下进行了标定实验,实验结果表明,该曲线拟合标定方法能够完成激光位移传感器的高精度标定,其定位精度为0.7%,平均测量误差可达0.012 mm,标定均方误差约为2.12×10 -5 mm 2。

For the precise calibration of laser triangular displacement detection based on position sensitive devices (PSD) with the influence of complex photoelectric noise, a joint calibration method based on multivariate adaptive Kalman filter (MAKF) and non-uniform B-spline is proposed. The nonlinear characteristic of displacement sensor is shown in detail by analyzing the measurement principle and computing methods. Aiming at the nonlinear problem, the method of curve fitting for the calibration is given. In consideration of the characteristic of curve fitting, in this paper, a preprocess method called MAKF is proposed for the photoelectric noise elimination. Then, the B-spline curve fitting model is built by dividing the knot vector nonuniformly, which makes the precision of the sensor further promoted. Calibration experiments are carried out under actual working conditions. The experimental results show that the curve fitting calibration method can complete the high-precision calibration of the laser displacement sensor. The positioning accuracy is 0.7%, the average measurement error can reach 0.012 mm, and the calibration mean square error is 2.12×10 -5 mm 2.