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A positional estimation technique for an autonomous land vehicle in an unstructured environmentThis paper presents a solution to the positional estimation problem of an autonomous land vehicle navigating in an unstructured mountainous terrain. A Digital Elevation Map (DEM) of the area in which the robot is to navigate is assumed to be given. It is also assumed that the robot is equipped with a camera that can be panned and tilted, and a device to measure the elevation of the robot above the ground surface. No recognizable landmarks are assumed to be present in the environment in which the robot is to navigate. The solution presented makes use of the DEM information, and structures the problem as a heuristic search in the DEM for the possible robot location. The shape and position of the horizon line in the image plane and the known camera geometry of the perspective projection are used as parameters to search the DEM. Various heuristics drawn from the geometric constraints are used to prune the search space significantly. The algorithm is made robust to errors in the imaging process by accounting for the worst care errors. The approach is tested using DEM data of areas in Colorado and Texas. The method is suitable for use in outdoor mobile robots and planetary rovers.
Document ID
19920041058
Document Type
Conference Paper
Authors
Talluri, Raj (NASA Lyndon B. Johnson Space Center Houston, TX, United States)
Aggarwal, J. K. (Texas, University Austin, United States)
Date Acquired
August 15, 2013
Publication Date
January 1, 1990
Subject Category
GROUND SUPPORT SYSTEMS AND FACILITIES (SPACE)
Meeting Information
i-SAIRAS ''90: International Symposium on Artificial Intelligence, Robotics and Automation in Space(Kobe)
Funding Number(s)
CONTRACT_GRANT: DAAL03-87-K-0089
CONTRACT_GRANT: NAG9-361
Distribution Limits
Public
Copyright
Other