The Study On Data Processing Method Of High-speed Video For Building Health Monitoring

With the development of science and technology,it is possible to capture rapid motion,for example,the collapse of housing,driving cars,the racing athletes,the bullets which is shooting out,etc.However,human being's naked eyes and the traditional measuring methods have been unable to capture the rapid motion and the trajectory of the transient object.High-speed videogrammetry(HSV)as a branch of photogrammetry,with its advantages of non-contact way and capturing and in the form of videos or sequence images per second,can record the high-speed objects' three-dimensional coordinates and effectively solve the problem.In recent years,high-speed videogrammetry at home and abroad has been gradually applied in civil engineering,aerospace,architecture and photogrammetry and other professional fields,it's also used in a series of experiments such as car crashing experiment,building's structural collapse experiment in the shaking table and wind tunnel laboratory and so on,as a measurement tool.Due to its low frame frequency and low resolution,traditional camera cannot meet the requirements of high speed videogrammetry.However,with the advent of CCD sensors and CMOS sensors,a new approach is provided for high-speed videogrammetry.Although the technology of high-speed camera based on CCD sensor is very mature,the camera is expensive,high energy consumption and its data is very complex to read,resulting in not being put into production and using in large quantities.In addition,the high-speed camera based on CMOS sensor in the current is still in the exploration stage.Therefore,the specific research of this paper is as follows: 1)This paper systematically introduces the origin,development and application of high speed videogrammetry,and analyzes the advantages and feasibility of high-speed videogrammetry based on CMOS sensor;2)This paper analyzes the necessity and importance of camera calibration based on CMOS sensor,compares various camera calibration methods and adopts the best method for the camera calibration of the CMOS high-speed camera used in this experiment to obtain the internal parameters;3)Because the high-speed camera can take thousands of images in a very short time,its data volume is extremely large,this paper will find how to deal with the video sequence images quickly and accurately,track and identify the target points,and improve the accuracy and efficiency of 3d reconstruction;4)In this experiment,high-speed videogrammetry technology is applied to the shaking table laboratory of XX university.The data acquisition of the collapse of reinforced concrete frame-shear wall structure is carried out by high-speed camera,and the obtained signals is decomposed to analyze the structural damage.After a series of experiments and analysis,this paper concludes that:The Zhang Zhenyou calibration for high speed camera based on CMOS sensor can improve the efficiency of calibration.Using elliptical target point tracking method to track the target point can improve the tracking speed.The signal decomposition of ESMD can be used to effectively obtain the abrupt point of collapse of buildings and conduct damage assessment.High-speed videogrammetry technology applicated in stereo video observation can improve the accuracy and efficiency of measurement acquired data processing and analysis,has great theoretical significance and practical application value.