Analysis Algorithm And Software For Dynamic Calibration Of Double-wheel SFC Testers

The pavement’s anti-skid performance is a key performance index to ensure road traffic safety.The calibration of the measurement model of the Double-wheel SFC Testers is the basic premise to ensure the accuracy of the measurement of the lateral anti-skid performance of the road surface.The transportation industry often uses comparison tests between multiple testers to improve the consistency of measurement results between devices,but this method lacks traceable standard values and can not achieve strict measurement model calibration.For this reason,this paper proposes a data sequence analysis and matching method based on wavelet transform and dynamic time warping algorithm on the basis of the reaction force restrained common excitation source dynamic calibration device,develops a corresponding data acquisition system,and realizes the dynamic calibration of the Doublewheel SFC Testers.The specific work of this paper is as follows:Aiming at the actual project acquisition requirements,a data acquisition instrument based on the YAV 16 AD acquisition card and a data acquisition software based on MFC are developed,and a data acquisition system is formed,which realizes the continuous acquisition,storage and display of data.A large number of dynamic calibration experiments have verified the real-time performance and stability of the acquisition system.Aiming at the noise interference in the dynamic calibration experiment,the wavelet threshold method is used to denoise the data sequence,and the relevant parameters are selected according to the actual engineering needs,and the performance evaluation experimental research is carried out;aiming at the inconsistency of the length of the data sequence caused by the difference in the movement process,this paper proposes to use the wavelet transform-based multi-scale analysis method to locate the singularity on the basis of analyzing the meaning of the data sequence,and intercepts the effective data sequence.A large number of qualitative and quantitative experimental results show the superior performance of denoising and interception methodsAiming at the problem of non-matching of data sequence feature points caused by different measurement frequencies and measurement results between devices,a data sequence segmentation de-duplication and sampling matching method based on dynamic time warping algorithm is proposed.This method performs dynamic time warping algorithm processing on the interception sequence,and according to the corresponding relationship between the sampling point path in the curved matrix and the regular interception sequence,the information of the matching peak points in the regular interception sequence is used to de-duplicate the curved path by sections.According to the segmented point information of the curved path after deduplication,the intercepted sequence is sampled and matched segmentally.The experimental results of multiple devices and multiple conditions verify the effectiveness of the matching method.Relying on the "Verification and Calibration Project of the Double-wheel SFC Testers in Use in the Transportation Industry",the dynamic calibration experiment was verified.The results show that the method in this paper has good compatibility with the reaction force restraint common excitation source dynamic calibration device,which meets the requirement of rapid calibration of the model parameters of the Double-wheel SFC Testers,which can effectively improve the measurement accuracy of the instrument and meet the actual requirements of engineering application.