An Active Safety System Using Two Laser Scanners for a Robot Tractor

Abstract

A 2D laser scanner was used for obstacle detection for autonomous vehicles for its high accuracy at both indoor and outdoor environment on the measurement of distance. Traditionally, the obstacle detection method was depended on the distance from an object to a laser scanner, and an obstacle was defined if the measured distance was less than a threshold. A shortage of the traditional obstacle detection method for a robot tractor is that a low obstacle cannot be detected when the height of the obstacle is lower than the height of the scanning plane of the 2D laser scanner. In this article, obstacle detection method using two 2D laser scanners is discussed. One laser scanner is mounted at the front and the other is mounted at the rear of the vehicle in order to cover the whole surroundings of the vehicle. The laser scanner was mounted look-at-down in order to detect a low obstacle. A test was carried out at an outdoor environment to verify the developed safety system. The test results indicate the developed system could detect obstacles with accuracy around 10 cm.