Research On Photogrammetric Slope Monitoring System Based On Smartphone Imaging

With the acceleration of my country's urbanization process,there are more and more deep and large foundation pit projects,and the requirements for slope monitoring have also increased.This paper designs a photogrammetric slope monitoring system that uses a non-measurement camera as an imaging tool and a direct linear transformation analytical method as a mathematical model.It is proposed to replace the traditional digital camera with a smart phone to improve the convenience and convenience of photogrammetric slope monitoring.The diversity of functions.Through calibration experiments and distortion studies on 6 smartphones,the feasibility of using smartphone imaging in the field of photogrammetry was proved.The stability and accuracy of the system were determined through indoor comparison experiments and engineering practices,and its effectiveness was determined.The scope of application in the field of slope monitoring.The research results have a marginal contribution to slope monitoring,and provide a research reference for the construction of the photogrammetric system on the intelligent mobile client platform.The main content and results of this research include:(1)Developed a camera calibration and distortion correction program based on the C++platform and OPENCV algorithm,and carried out calibration experiments on 6 smartphones including Huawei P30 and iphone11 promax.The results showed that the smartphone camera's imaging distortion is small and meets the requirements of photogrammetry.Application requirements of slope monitoring system;(2)Developed a digital close-range photogrammetry system with smart phone camera as imaging tool,VS2015 as development platform,C++ as development language,and direct linear transformation method as mathematical model,which realized unknown point coordinate measurement,camera calibration and image distortion Correction and other functions;(3)The indoor coordinate measurement experiment was carried out,and the imaging measurement errors of Huawei P30,iphone8 Plus and Nikon digital cameras were compared using this system.The results showed that the accuracy of the imaging measurement of smart phone cameras was slightly higher than that of digital cameras;(4)The engineering practice was carried out.The Huawei P30 night scene mode was used to take photos.The system was used to obtain the coordinates of the monitoring points and compared with the standard values.The results showed that the system has good accuracy and is suitable for monitoring the accelerated creep phase of slopes.