Training a terrain traversability classifier for a planetary rover through simulation. (26th October 2017)

• Record Type: Journal Article
• Authors: Hewitt, Robert A; Ellery, Alex; de Ruiter, Anton
• Is Part Of: International journal of advanced robotic systems. Volume 14:Number 5(2017:Sep./Oct.)
• Publication Date: 2017-10-26
• Subjects: Planetary rovers -- planetary exploration -- neural networks -- autonomous navigation -- LiDAR -- classification; Robotics -- Periodicals; Robotics; Periodicals; 629.892
• DOI: 10.1177/1729881417735401
• Languages: English
• ISSNs: 1729-8806

Abstract

A classifier training methodology is presented for Kapvik, a micro-rover prototype. A simulated light detection and ranging scan is divided into a grid, with each cell having a variety of characteristics (such as number of points, point variance and mean height) which act as inputs to classification algorithms. The training step avoids the need for time-consuming and error-prone manual classification through the use of a simulation that provides training inputs and target outputs. This simulation generates various terrains that could be encountered by a planetary rover, including untraversable ones, in a random fashion. A sensor model for a three-dimensional light detection and ranging is used with ray tracing to generate realistic noisy three-dimensional point clouds where all points that belong to untraversable terrain are labelled explicitly. A neural network classifier and its training algorithm are presented, and the results of its output as well as other popular classifiers show high accuracy on test data sets after training. The network is then tested on outdoor data to confirm it can accurately classify real-world light detection and ranging data. The results show the network is able to identify terrain correctly, falsely classifying just 4.74% of untraversable terrain.