Design Of Bridge Deflection Detector Based On Laser Triangulation Displacement Measurement Principle

Bridge deflection is an important parameter to evaluate the safety performance of bridge,it is an important index of bridge load experiment and health monitoring,so it is necessary to monitor it for a long time to evaluate its load capacity and health risk condition,and to guide the maintenance and maintenance of bridge.With the improvement of the security performance of the large-scale infrastructure,the traditional manual measurement method has been difficult to meet the needs of the automatic risk assessment of the bridge,so it is urgent to research and develop the real-time monitoring device of the automatic bridge deflection.Based on the analysis of the principle,method and characteristics of the traditional torsion parameter,the paper studies and designs a bridge's deflection parameter detecting instrument on the basis of the principle of laser triangulation displacement measurement.Based on the principle of high precision automatic detection of bridge deflection parameters,the paper designs the scheme,hardware selection and hardware circuit design,image processing algorithm and program design,experiment analysis and calibration and other key technologies,designs the online detection system of deflection parameters which can be applied to a variety of bridges,and verifies its rationality and validity through laboratory simulation experiments.In this paper,the deflection mechanism of infrastructure components is studied theoretically,a deflection parameter detection model based on the principle of laser triangulation displacement measurement is proposed according to the requirements of engineering measurement of bridge deflection.Secondly,by analyzing the theoretical model of laser triangulation measurement,a particle swarm algorithm based on multistage penalty function is proposed to optimize the optical parameters in the imaging optical path,which can improve the design of the detection system based on the high-speed measurement,real-time image processing,and improve the design of the digital image processing.Finally,aiming at the characteristics of CCD sampling data,the algorithm of spot image filtering and spot location and the solution of measurement results are designed,and the process of its realization in DSP is given,which plays an important role in improving the precision of the system.At the same time,by setting up an experimental platform,the testing simulation experiment is carried out in the laboratory to verify the performance of the system,the stability of the system is tested,the calibration and the non-linearity of the system is analyzed in detail.