Combining Real and Synthetic Terrain for Testing Planetary Landers and Rovers
- Paper number
IAC-08.A3.2.INT11
- Author
Dr. Iain Martin, University of Dundee, United Kingdom
- Coauthor
Dr. Steve Parkes, University of Dundee, United Kingdom
- Coauthor
Dr. Martin Dunstan, University of Dundee, United Kingdom
- Coauthor
Mr. Mark McCrum, University of Dundee, United Kingdom
- Year
2008
- Abstract
The Planet and Asteroid Natural Scene Generation Utility (PANGU) is a software tool for simulating and visualizing the surface of various planetary bodies. This is used to support the development and testing of planetary landers that use computer vision for surface relative navigation and hazard avoidance on landing. PANGU can generate artificial surfaces representative of the Moon, Mercury, Mars, asteroids, and comets, and provide surface images to simulate a vision system on a lander or rover. This paper describes how real and synthetic terrain can be combined in a hierarchical model to simulate planetary surfaces at the varying resolutions required for planetary lander through a descent sequence, and a rover on the surface. High resolution Digital Elevation Models (DEMs) are increasingly becoming available for some planetary surfaces such as Mars and the Moon. When considering generating a simulation of a planetary surface for a specific mission it may also be possible to obtain DEMs specifically for this mission from orbiting spacecraft. These DEMs could then be used as a basis for generating terrain models that could be used to test landers and rovers. However, these DEMs may not be complete, they may include some “holes” which are filled using interpolation and they may not be of sufficiently high resolution to simulate a lander descent or a surface rover. This paper describes how real terrain DEMs can be enhanced using a hierarchical terrain model and fractal expansion to create higher resolution terrain models onto which high resolution synthetic features such as craters and boulders can be added to create realistic surface models that are a combination of real and synthetic terrain. The issues of feature blurring through fractal expansion are considered and techniques to fill holes in DEMs are reviewed. Feature identification and replacement is considered as a technique to improve the sharpness of fractally expanded features that would otherwise appear unrealistically blurred at high resolutions. A Lunar South Pole lander is considered as a mission example to show how PANGU can be used to create a model of a specific planetary surface by combining available surface DEMs with fractal expansion in a hierarchical surface model together with the addition of synthetic small scale features such as craters and boulders.
- Abstract document
- Manuscript document
(absent)