摘要 融入式测量系统需要配合手持式测量装置(手持式测靶)进行工作,所以针对测靶探针尖端中心位置(测头)的标定是必不可少的过程,目前主要用最小二乘法对其进行标定,该方法容易受到微小位置误差等噪声的影响从而产生较大的标定误差,针对此问题,在最小二乘法的基础上对传统标定算法进行改进,利用正则化总体最小二乘法(Regularized Total Least Squares,RTLS)对测靶进行标定。首先经过提取和匹配得到测量装置上特征点的坐标,然后根据特征点的坐标得到固定球半径的约束方程用于建立测头中心位置的误差变量(Errors-In-Variables,EIV)模型,利用Tikhonov正则化和L曲线方法来搜索EIV模型的最优解得到最终标定结果。实验结果表明,该方法X,Y,Z方向上的定位精度重复性分别为0.042 mm,0.074 mm,0.071 mm,远低于传统方法的重复性(0.150 mm,0.126 mm,0.158 mm),从而验证了该方法相对于传统的标定方法可以更有效准确地标定手持式测量装置,并且简单快捷,提高了现场测量效率,可以应用于实际现场检测过程中。 The immersive measurement system needs to work with a handheld measurement device(handheld target),so the calibration of the center position(probe)of the probe tip of the target is an indispensable process.At present,the least square method is mainly used to calibrate the handheld measurement device,this method is susceptible to the influence of noise such as small position errors and thus generates large calibration errors.In response to these problems,the traditional calibration algorithm is improved on the basis of the least square method,and the target is calibrated using Regularized Total Least Squares(RTLS).First,the coordinates of the feature points on the measuring device are obtained by extraction and matching,and then the constraint equation of the fixed sphere radius is obtained according to the coordinates of the feature points.It is used to establish the errors in variables(Errors-In-Variables,EIV)model of the probe center position,using Tikhonov Regularization and L curve method are used to search the optimal solution of EIV model to obtain the final calibration result.The experimental results show that the repeatability of the positioning accuracy of the method in the X,Y,and Z directions is 0.042 mm,0.074 mm,and 0.071 mm,which is much lower than the repeatability of the traditional method(0.150 mm,0.126 mm,0.158 mm).It is verified that this method can calibrate the handheld measurement device more effectively and accurately than the traditional calibration method,and it is convenient,which improves the efficiency of on-site measurement and can be applied to the actual on-site inspection process.
出处 《自动化与仪器仪表》 2021年第4期74-81,共8页 Automation & Instrumentation
基金 国家自然科学基金(No.51975408,51721003) 天津市自然科学基金(No.18JCYBJC19400):渠道:国防科工局基础产品创新项目(No.62.1)。
关键词 融入式测量系统 手持式测靶 测头标定 误差变量模型 TIKHONOV正则化 immersive measurement handheld measuring target probe calibration errors-in-variables model tikhonov regularization
