A Laser Based Bridge Deflection Image Detector Based On DM642

Bridge deflection is an important parameter of bridge safety performance evaluation.It is necessary to carry out long-term monitor the bridge deflection,evaluate the load capacity of the bridge,and guide the maintenance and repair of the bridge.With the continuous improvement of the safety requirements of the large-scale infrastructure,the traditional manual measurement method can't meet the needs.Therefore,it is urgent to study and develop the real-time monitoring system of high precision and high efficiency automatic bridge deflection.Based on the characteristics of the traditional bridge deflection detection principle,method and equipment performance,this project researches and designs the laser based bridge deflection image detector.This paper studies the hardware selection and hardware circuit design,image processing algorithm and program design,upper computer software design,error analysis and precision correction and other key technologies for high precision automatic detection process of bridge deflection,then,design the bridge deflection detection system can be applied to a variety of environment,and verify its rationality and effectiveness by the experiment.First,theoretically studies the deflection mechanism and mathematical model of the infrastructure components,this paper proposed a deflection parameter detection model that based on laser reference and digital image processing.Next,study the energy uniform parallel laser light source generation and emission optical models,selection and analysis of optical image acquisition system for the optical imaging system by the optical measurement principle,A laser emission subsystem and imaging target reception subsystem is designed based on semiconductor laser emission and auto leveling in order to obtain a clear and energy-focused laser spot image.Then,design image processing hardware,software and core algorithms for image real-time processing technologies based on image processing chip DM642.A digital image processing system with DM642 as the core processor is proposed to study the real-time accurate processing of laser spot image processing model and algorithm,and improve the capacity of real-time processing by using ROI rapid detection based on pyramid model.Build the visual imaging CCD camera distortion correction model and processing algorithms to precise positioning of the center of the spot.Finally,design the upper computer software for the laser reference bridge deflection detection system prototype,and remote data transmission between the detection system and the computer terminal by wireless communication for the real-time monitoring function of bridge deflection.Experiment on the bridge deflection detection system prototype and correct error by the experimental data.