Research On Reconstruction Of Horizontal And Vertical Alignment Parameters Based On SPEEDBOX＿INS

Road is an integral part of road traffic system.As the "skeleton" of the road,the horizontal and vertical alignment parameters have a direct impact on the safety of vehicle operation.Therefore,how to obtain the horizontal and vertical alignment parameters quickly and accurately has a very urgent practical demand and application prospect for road safety assessment,dangerous road section prediction,road reconstruction and expansion,traffic accident responsibility identification.In this paper,the research of road alignment parameter reconstruction technology is based on SPEEDBOX＿INS.The reconstruction model of horizontal and vertical alignment parameters is established by synthetically using the research methods of road alignment identification technology,alignment adjustment technology and iterative optimization theory.so as to realize the reconstruction of alignment parameters.The main research contents are as follows:In view of the problem of road alignment recognition,on the basis of in-depth analysis of the existing scheme,vehicle azimuth data and road slope angle data are used to carry out alignment recognition research.Considering the high sampling frequency of slope angle data and many data burrs,the moving average filter is used for data filtering.In this paper,a coarse segment method based on search is proposed to analyze the slope characteristics of azimuth and slope angle data,and to realize the accurate identification of horizontal curve straight curve node,vertical curve straight Circle node and line type through logical discrimination.The road alignment fitting process is easy to be interfered by gross errors,and the accuracy is poor.Based on the adjustment theory,the adjustment models of straight line and circular curve in the center of gravity coordinates are established respectively.Considering the interference of the gross error data and the linear data which are not to be adjusted,robust estimation is introduced to carry out the weight selection iterative calculation of the linear parameters.It can effectively improve the fitting accuracy of linear parameters of straight line and circular curve.Given the linear parameters of straight line and circle,the whole linear connection is carried out according to the highway linear design theory,and then the coordinate information of the road pile point is obtained.Finally,the reconstruction of the road linear parameters can be realized.Using the above research results,the reconstruction system of road alignment parameters is developed on VS2015 platform.According to the requirements of data reading and fast processing,the SPEEDBOX data reading module based on EXCEL program interface function,ADO development technology and SQL query technology is designed.In this paper,based on the adaptive coordinate system technology of data capacity,the effective display of current vehicle operation status data in a period of time can be realized by data interception.Finally,taking the xiahetan section of Xi’an Huanshan highway(first class,speed limit 80 km / h)as an example,the validity of the reconstruction system of road alignment parameters is verified by comparing with the highway alignment specifications.