The Binocular Monitoring System Of Tree Barriers Near Transmission Lines Based On Stereo Vision

The tree barrier has always been a great threat to transmission lines,and it is considered to be the main cause of several serious blackouts.However,the existing detection and protection methods cannot handle the contradiction between transmission lines and tree barriers around them.Aiming at this problem,a binocular monitoring system based on stereo vision has been proposed.The results of theoretical research and application test indicates that the system can monitor tree barriers near transmission lines with high precision in real-time.The method effectively improves the safety and reliability of power lines operation.Firstly,the catenary equation of overhead transmission lines is deduced.To find the solution of lines equation,a method based on ultrasonic ranging and inclination is proposed.Then the imaging principle of the camera is seen as reference to establish a three-dimensional model of the other targets around transmission lines.Combining the model of transmission lines and that of other targets,the mathematical model of the binocular system is obtained,and the solution scheme of distance between transmission lines and tree barriers is given in the model.Secondly,the influencing factors of measurement errors are studied based on the analysis of the principle of stereo vision and algorithms of stereo matching.Then a variable window local matching algorithm based on region of interest is raised to reduce the distance error,which can effectively raise the accuracy of three-dimensional measurements for tree barriers.Finally,the binocular monitoring system consists of hardware device and software is designed.The sphere-shaped terminal device is powered by induction circuit module and super capacitor,and it can collect operating data to establish a binocular monitoring model of transmission lines via binocular camera,ultrasonic probe and acceleration sensor.The software system implements user management and configuration parameters for the terminal device,while sending early warning information to the user when the monitoring system detects that the tree barrier is too close to ensure transmission lines run safely.Field installation experiments indicate that the system meets the requirements of protection of transmission lines.