Research On Monitoring Technology Of Ground Settlement Based On Fourier Transform Profilometry

The ground settlement is prevalent and neglected environmental geological problems,in today's world of city modernization.the continuous and gradual accumulation of geological disasters,mainly by the process of rapid economic development in the increasing development of underground resources,housing cracks,building shape,frequent flooding,local collapse and other problems caused by serious constraints the su,stainable development of regional economy,threat to human life and property safety.The traditional methods of ground settlement monitoring mostly adopt the simple monitoring equipment,such as leveling,GPS,etc.,there are many deficiencies in the control process and the output effect.Therefore,it is necessary and urgent to study on the surface subsidence.According to the existing observation of long cycle,low efficiency of traditional monitoring methods,the problem of poor real-time,the color fringe projection as the research object,use the camera calibration with fringe projection profilometry technology,3D surface recovery measured contour information,proposes a method of subtraction method and NCC based fusion of ground settlement to monitor and verify the feasibility.The specific work is as follows:firstly,in order to promote the normal follow-up research and experiment simulation,build a measurement system based on fringe projection profilometry,its functions include fringe projection,deformation fringe pattern acquisition,and complete the calibration experiment,obtain the camera internal and external parameters;second acquisition of the measured ground motion simulation data,analyzed the advantages and disadvantages of fit 3D measurement method commonly used optical and the content of this paper,choose the tri band fringe projection profilometry based on grounde settlement monitoring as theoretical model,discussed the background subtractive color,empirical mode decomposition,decoupling,variable precision phase unwrapping and other related technologies;on this basis,simulation experiments for the monitoring of surface movement information.The experimental results show that the projection method of sine stripe structured light projection technology in monitoring the feasibility of settlement on the ground;in order to determine the degree of deformation of surface.On the basis of existing research,put forward a method of subtraction method and NCC based on the combination of image matching,and compared with the traditional NCC algorithm,the simulation results show that the fusion algorithm in processing time than the NCC algorithm to reduce at 2s,Better real-time performance.The surface subsidence monitoring experiment indicates that using the method of fringe projection profilometry,realizes the real-time monitoring of surface deformation,improve the monitoring process of processing time,the system has stronger robustness and adaptability,accuracy and the system reaches the mm level.Has certain social value in the ground settlement monitoring.