Moving Target Detecting And Recognition Under The Laser Scanning

Moving target detection and recognition has been an important research topic in computer vision. Utilizing laser to capture data can obtain clear spatial relationships of target with very little time and low amount of data per frame. Compared with other sensors for data acquisition, laser range finder is an active measurement. It has little limits of environment. Its scanning area is larger than other scanning system. So using laser for moving target detection and recognition has unique advantages.In this paper, based on the research of vibration mirror type laser scanning system and the practical test on the scene, we initialize the system through the precise distance measurement function of laser range finder and the step move function of stepper motor, which includes finding the zero position of galvanometer deflection angle and configuring the parameters of the vibrating mirror type laser scanning system. After analyzing the overall structure and working principle of vibration mirror laser scanning system, according to the possible error and noise interference, we adopt the median filtering and the shift of data points to reduce the influence of error. Then we establish three-dimensional coordinates based on the relationship between location of the scene and laser system, and convert a point cloud data into the three-dimensional space. In this space, we create static background templates, according to the present in the form of background in the laser data, for the following moving target detection process.In moving target detection, background subtraction method is introduced to distinguish static background and region of interest. We detect the moving targets in the region of interest based on the continuity property and spatial location relationships between the data points. Then according to the altitude variation of data points and the target height through the vertical scanning, we can calculate and adjust the vertical mirror deflection angle to make scanning system can stably detect, or track moving targets. In the moving target recognition, the template matching method is adopted for target classification. The template database is created according to the differences of target laser points in different distance. Finally, experiments demonstrate the effectiveness of our method for target detection and recognition.