CHARACTERIZATION OF LASER RANGE FINDER FOR IN-FIELD NAVIGATION OF AUTONOMOUS TRACTOR

摘要

Infield navigation of agricultural vehicle needs the robust positioning method. This study aims to develop the positioning method to localize the object in the field using the outdoor laser range finder for an autonomous tractor. A laser range finder was mounted on the centerline of Topcon tripod, so that it profiles the surroundings within 100° horizontally from -50° to 50°. It is complicated to accurately detect and localize the corners and occlusions of natural landmarks in the outdoor environment from 2D laser range scans. So the field experiment was carried out to measure the flat rectangular, cylindrical and trapezoidal reflectors to localize the object in the 20m×20m field. The position of reflectors in x-y Cartesian coordinates were estimated using the least square method through the line fitting for rectangular and trapezoidal, and circle fitting for cylindrical reflectors. The shapes of reflectors and target surface properties that may potentially affect the sensing performance in the outdoor navigation were investigated.