June 2003
Monster Trucks on Mars
By Patrick L. Barry and Dr. Tony Phillips
We all know what Mars rovers look like now: Robotic platforms, bristling with
scientific instruments, trundling along on small metallic wheels. Planetary
rovers of the future, however, might look a little different-like miniature
monster trucks!
Enormous, inflatable tires can easily roll right over the rocks and rugged
terrain of alien planets, just as they bound over old cars like as many speed
bumps.
That's the idea behind a novel concept for robotic planetary rovers known as the
"big wheels inflatable rover." Unlike rovers similar to the Sojourner robot that
explored the surface of Mars in 1997 that depend on instructions sent from Earth
or complex programmed intelligence to steer through rough terrain, this rover
has three beach ball-like tires roughly five feet across that make it a true
off-road vehicle.
"We sent this rover out to Death Valley, to a place called Mars Hill that has a
general geological formation like Mars, and nothing could stop it," says Jack
Jones, the mastermind of the inflatable rover concept at JPL. "It just kept
going and going and going."
 |
| The "Big Wheels" inflatable rover
doesn't mind a few boulder- sized rocks, no matter what planet they're on! |
Lots of current research is devoted to developing advanced robotic intelligence
that allows rovers to detect rocks in their path and maneuver around them. The
alternative to such on-the-spot intelligence is tedium: Ground controllers on
Earth working out the maneuvers by hand and waiting an hour or more for the
instructions to travel to the distant planet.
A "big wheels" rover would need such computer intelligence to avoid very large
boulders, but Jones asks, "Why worry about every little rock, pebble, and crack
when you can just roll right over most of them?"
Jones imagines a scenario where multiple inflatable-wheel rovers could be sent
out to explore the Martian terrain-easily and quickly traversing the rugged
terrain. Samples gathered by the rovers could be returned to a central,
stationary laboratory module for detailed analysis.
"The Martian surface is really very, very rough with a lot of rocks, and to be
banging this laboratory equipment up and down over all of these rocks aboard the
rovers doesn't make much sense," Jones says. "I suspect it might be better to
leave it in a central location."
At the moment it's all very speculative; NASA currently has no definite plans to
send inflatable rovers to Mars. But who knows, one day monster truck-like
vehicles could be zipping over Mars' rough, red surface.
Kids can baffle their friends with a robot puzzle (including a "Big Wheels"
rover) they make themselves at
http://spaceplace.nasa.gov/robots/robot_puzzle.htm. For adults, find out
more about NASA's inflatable rover program at
http://www.jpl.nasa.gov/adv_tech/rovers/summary.htm.
This article was provided by the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration.