The Wheel Abrasion Experiment-how abrasive is the Martian dust?

The Wheel Abrasion Experiment (WAE) is one of the technology experiments on the Mars Pathfinder Rover (Sojourner) which will land and begin operations on the planet Mars in July, 1997. By abrading thin film metallic surfaces on one of Sojourner's wheels, and detecting the resulting changes of reflectivity with a special photovoltaic sensor, WAE will measure the abrasive characteristics of the Martian sand or dust. In this paper, the authors review the purpose of the experiment its general design and functionality, specifics about the wheel design and construction, the ground tests necessary for it to yield meaningful answers and what it might tell us about the surface of Mars for use on future robotic rovers and possible future manned exploration. Ground tests have already revealed the possibility of significant charging on wheeled vehicles in the Martian atmosphere. Further tests may enable the better design of future vehicles for use on Mars.