摘要
Abstract
The deflection measurement of main girder of gantry crane is a key structural monitoring project.The existing deflection measurement methods of main girder need to be measured after shutdown,which have some problems such as cumbersome operation and extremely sensitive to outliers,resulting in inaccurate measurement.In this paper,a new method for measuring the deflection of main girder based on direct linear transformation is proposed.Based on the traditional direct linear transformation algorithm,the objective function of minimizing the L1 norm of outliers is introduced.By considering the residual and posterior variance,the objective function is solved by using the Soft-IPOD method,which improves the robustness of outlier identification and elimination and effectively avoids the inaccuracy of deflection measurement caused by outliers.Results of simulation and field experiments show that the algorithm can accurately identify and reject outliers,and the accuracy of deflection measurement is obviously better than that of traditional methods,with an average error of less than 1.5 mm and a relative error of less than 5%.This method has excellent performance in computing speed,which is nearly 20 times faster than the direct linear transformation algorithm based on RANSAC.In the engineering experiment,this method shows excellent performance and provides a feasible solution for the rapid and accurate measurement of the deflection of the main beam of the gantry crane.关键词
门式起重机/挠度测量/直接线性变换/异常值/L1范数/Soft-IPODKey words
gantry crane/deflection measurement/direct linear transformation/abnormal value/L1 norm/Soft-IPOD分类
机械制造
