Visual vehicle detection and tracking based on the 'sign pattern'

摘要

Real-time vehicle detection and tracking applicable for outdoor mobile robots on a structured road is proposed. The method is based on a locomotion strategy known as 'sign pattern based stereotyped motion'. The sign pattern of a vehicle is the shadow underneath. The robot detects a vehicle from a distance of 30 m with a domestic video camera and extracts its front shape in real-time processing. The distance between the robot and vehicle, and the velocity and width of the vehicle are estimated during the tracking process. In addition, the center of the vehicle in two-dimensional imaging is determined during the tracking process to estimate the type of motion. The accuracy rate of vehicle width measurement based on the shadow underneath is better than 90% in practice, which can be adequately used for vehicle avoidance applications. The applied method has been tested on roads covered with different types of shadows as well as under different weather conditions. The results of the experiments verify the validity of the method.