Application Research Of Smartphone And UAV In Dynamic Deformation Monitoring

With the progress of science and technology,the scale of construction engineering continues to expand,the building structure becomes more and more complex,and the safety monitoring requirements for the building structure continue to grow.How to rapidly and reliably monitor the dynamic deformation of the building structure is an important problem concerned engineers and technicians.Digital close-range photogrammetry technology has the advantages of non-contact,multi-point,and fast monitoring,and is often used in dynamic deformation monitoring of building structures.In recent years,digital cameras have been applied in this field.Digital cameras have stable performance and low cost,but they need to be placed on stable ground.The theory and method of applying digital cameras to dynamic deformation monitoring have been relatively mature.On this basis,it is possible to apply smartphones and UAVs to dynamic deformation monitoring.Smartphones have stable imaging,outstanding ease of use,and quick and convenient deployment.UAV has low cost and high flexibility,and can enter areas difficult to reach by human and measuring instruments.Its camera and body can adjust its attitude flexibly,providing richer monitoring perspectives for deformation monitoring.The application of smartphones and UAVs in dynamic deformation monitoring is conducive to improving the flexibility of monitoring and the ease of use of measuring instruments,which is conducive to further improving the deployment speed of dynamic deformation monitoring,and can play a positive role in the rapid dynamic deformation monitoring of building structures.For this,based on the digital close shot photogrammetry technology,proposed to smartphones and UAVs and photography-time baseline parallax method combining proportion transformation,dynamic deformation monitoring,and put forward a kind of smartphones,and UAV cooperative dynamic deformation monitoring method,among them,aiming at the problem of UAV movement occurred in the process of monitoring,a data processing optimization method is proposed.The validity of the above theories and methods is verified by experiments.The main research contents are as follows:（1）Aiming at the lens distortion problem,the camera calibration and distortion correction program PDMS（Photography Dynamic Monitoring System）based on Open CV Zhangs calibration method is developed in the Qt environment to calibrate the cameras of smartphones and UAVs.The calibration parameters of PDMS are compared with those of MATLAB Camera Calibrator.The calibration results are basically the same,and the average reprojection error of PDMS is lower than that of MATLAB Camera Calibrator.The measurement accuracy of smart phone and UAV was verified through experiments.Subsequently,the camera calibration parameters of PDMS were used to correct the distortion of photos taken by smartphones and UAVs.（2）In view of the problem that the airborne camera of UAV still has slight movement during the dynamic deformation monitoring,which leads to the deviation of monitoring data,a data processing optimization method is proposed.This method is simple and easy to use,without any pre-installed signs.In this paper,the effectiveness and reliability of the data processing optimization method are verified in the collaborative monitoring experiment of smartphones and UAVs.（3）A collaborative monitoring method based on smartphone and UAV is proposed,and the feasibility of the method is verified through experiments.The measurement accuracy of smartphone is verified in the experiment,to evaluate the measurement accuracy of UAV in the experiment.UAV can monitor the points that can’t be monitored by smartphone.The cooperative monitoring between UAV and smartphone can reflect the deformation mechanism of monitoring structure more comprehensively.（4）Through steel structure experiment,simulated landslide experiment,and bicycle gym experiment,it has been proved that smart phones can achieve the same monitoring effect as digital cameras,and it is found that equipment supporting high-frequency shooting has the advantage of higher monitoring frequency when monitoring high-frequency vibration targets.（5）Through steel structure curtain wall experiment and overhead corridor experiment,the feasibility of applying UAV in dynamic deformation monitoring is explored.The results show that UAV has higher flexibility than the common digital camera in dynamic deformation monitoring of large structures.