AN OBSTACLE IDENTIFICATION ALGORITHM FOR A LASER RANGE FINDER-BASED OBSTACLE DETECTOR

摘要

The capability of detecting and identifying obstacles on the expected path and taking appropriate collision avoidance actions automatically is critical for safe operation of autonomous agricultural vehicles. This article presents an obstacle detection and identification algorithm for an on-tractor laser range finder-based obstacle detector. This algorithm consists of a template matching function and a Kalman filter for detecting the location of an obstacle, reconstructing the silhouette of the detected obstacle, and estimating its relative motions. Field validation test results verified that this obstacle detector was capable of detecting a moving object within a semicircle of 8 m radius and reconstructing a 2D silhouette of the obstacle progressively in real time. The errors of this obstacle detector in estimating the position, speed, and moving direction of the obstacle relative to the tractor were 0.052 m, 0.11 m s -1 , and 1.2 ° , respectively. Such accuracies are sufficient for providing safety warning and collision avoidance for autonomous tractors in field operation