Study On The Algorithm Optimization Of CPⅢ Plane Network Considering The Systematic Error

The Track Control Network (CPIII), which is the most basic track measurement control network in High-speed Railway, is made up of CPIII leveling network and CPIII plane network. The CPIII plane network is controlled by the basic horizontal control network (CPI) and the route horizontal network (CPII), and it is measured by the free-stationing side-angle intersection method after the substructure engineering is finished. Before2008, it mainly used German technology for the measurement and data processing of CPIII plane network in our country, but since2008, in order to break the foreign technology blockade and meet the demand of developing high-speed railway, many domestic companies and scientific research institutes had begun to study the technique of CPIII, evolving a theory of how to establish it, which has independent intellectual property, and finally developed many data processing software suitable in China. Unfortunately, the existing software takes a lot of time to deal with long CPIII section, which is far from scientific reasonableness and software optimization. In addition, there still remains quite a number of key technical problems have not been studied distinctly, such as fixed the coordinate of CPIII free net adjustment on the coordinate system of CPI/CPII, the facilitates programming algorithm of calculate the longitudinal and lateral closing error of CPIII plane network, etc. For problems mentioned above, based on the analysis of the exiting algorithms, some technical question of CPIII was discussed in this paper as well as the adjustment algorithm was optimized. The thesis mainly contains the following:Firstly, the existing theory is introduced, which contains calculate the preliminary coordinates of the unknown point, the linear approximation of observation equation, the method to weigh the observed value, the adjustment method of free network, the constraint adjustment method and the error evaluation.Secondly, after summarizing the systematic error in the observed value of CPIII plane network, the adjustment method after adding the fixed error parameter and the ratio error parameter in the side observation equation, the method to fix the known coordinate or the known azimuth during data processing, the adjustment method after eliminating the orientation angle from the normal equation, the hypothesis testing of additional systematic parameters are introduced.Thirdly, based on the study of the three parameters coordinate transformation and the four parameters coordinate transformation, the influence of the systematic error in the side and the known coordinate on the coordinate transformation parameters and the residual error are analyzed in this paper, as well as the possibility to use three parameters coordinate transformation to fix the coordinate of CPIII free net adjustment on the coordinate system of CPI/CPII, besides, a facilitates programming algorithm to calculate the longitudinal and lateral closing error of CPIII plane network, a optimization sorting method of net point, and a compress storage method of sparse matrix are introduced.At last, The Engineering Surveying Data Adjustment Program ("SDAP" for short) was designed using the proposed algorithm. After verifying the accuracy of the software, many real CPIII measurement data was processed with SDAP and then analyzing the results combined with the theory introduced in this paper.