Rover Team Tests Mars Moves on Earth

MEDIA RELATIONS OFFICE
JET PROPULSION LABORATORY
CALIFORNIA INSTITUTE OF TECHNOLOGY
NATIONAL AERONAUTICS AND SPACE ADMINISTRATION
PASADENA, CALIFORNIA 91109. TELEPHONE (818) 354-5011
http://www.jpl.nasa.gov

Guy Webster (818) 354-6278
Jet Propulsion Laboratory, Pasadena, Calif.

News Release: 2005-072 May 6, 2005

Rover Team Tests Mars Moves on Earth

Mars rover engineers are using a testing laboratory to simulate
specific Mars surface conditions where NASA's rover Opportunity
has spun its wheels in a small dune. Careful testing is
preceding any commands for Opportunity to resume moving to get
out of the dune and continue exploring.

The rover team at NASA's Jet Propulsion Laboratory, Pasadena,
Calif., has cooked up recipes combining various sandy and
powdery materials for the best simulation on Earth of the dune
where Opportunity dug itself in to wheel-hub depth last week.
The team has not asked Opportunity to turn its wheels at all
since the rover bogged down during a drive on April 26.

"We choose to proceed cautiously, so we don't expect to begin
actually driving out of the dune before next week, possibly
later," said Jim Erickson, rover project manager at JPL. "Both
Opportunity and Spirit have already provided many more months
of scientific exploration than anyone expected. By taking good
care of them, we hope to keep them exploring for more months to
come. Tests so far have sustained our optimism about
Opportunity's ability to drive out of this dune, but we have
more testing ahead to understand how robust that capability
is."

Opportunity had driven about 40 meters (131 feet) of a planned
90-meter (295-foot) drive on the rover's 446th martian day when
its wheels began slipping. The rover was driving backwards at
the time. The team frequently alternates between backwards and
forwards driving to keep wheel lubrication well distributed.
The wheels kept rotating enough times to have covered the rest
of the distance if they hadn't been slipping, but the rover
eventually barely inched forward. After a turn at the end of
the planned drive, Opportunity sensed that it had not turned
properly and stopped moving.

Opportunity is positioned across the ridge of an elongated dune
or ripple of soft sand that is about one-third meter (one foot)
tall and 2.5 meters (8 feet) wide. "We've climbed over dozens
of ripples, but this one is different in that it seems to be a
little taller and to have a steeper slope, about 15 degrees on
part of its face," said Mark Maimone, a JPL rover mobility
engineer.

Last week, engineers arranged a simulated dune using sand that
was already at JPL's rover testing facility and put a test
rover into a comparably dug-in position. The test rover had no
difficulty driving away, even when sunk in belly-deep. However,
that sand offered better traction than the finer, looser
material that appears to make up the surface at Opportunity's
current position. "We needed to do tests using material more
like what Opportunity is in, something that has a fluffier
texture and cakes onto the wheels," said JPL rover engineer
Rick Welch, who is leading the tests.

Experimenting with different mixtures, engineers and scientists
came up with a recipe that includes play sand for children's
sandboxes, diatomaceous earth for swimming pool filters and
mortar clay powder. Then they went to several home supply and
hardware stores to find enough bags and boxes of the
ingredients to make more than 2 tons of the simulated Mars sand
for more realistic mobility tests, said JPL rover mobility
engineer Jeff Biesiadecki.

Dr. Robert Sullivan of Cornell University, Ithaca, N.Y., a
rover science team member, worked with engineers in the JPL
testbed to match the properties of the test sand as closely as
possible with those of the sand beneath Opportunity, based on
images of wheels and wheel tracks on Mars. "We found that when
the wheels dig in, the material we're using does stick to the
wheels and fills the gaps between the cleats, but it doesn't
stick when you're just driving over it. That's good because
it's the same as what we see in the images from Opportunity,"
Sullivan said.

Experiments indicate that in this more powdery material, the
test rover positioned comparably to Opportunity can drive out
after some initial wheel-spinning. More testing, analysis,
planning and review will precede any actual commands for
Opportunity to begin driving away from the dune.

Meanwhile, Opportunity has been using its cameras to study its
surroundings at the edge of a region called "Etched Terrain."
Since landing more than 15 months ago, it has driven 5.35
kilometers (3.32 miles). Spirit, halfway around Mars, has
recently been using all of its research tools to examine an
outcrop called "Methuselah," the first outcrop of layered rock
that Spirit has found. The rover has also been taking short
movies of dust-carrying whirlwinds called "dust devils." On
some afternoons, the rover sees several at once moving across
the plain. Spirit has driven a total of 4.31 kilometers (2.68
miles).

JPL, a division of the California Institute of Technology in
Pasadena, has managed NASA's Mars Exploration Rover project
since it began in 2000. Images and additional information about
the rovers and their discoveries are available on the Internet
at
http://www.nasa.gov/vision/universe/.../mer_main.html
and http://marsrovers.jpl.nasa.gov .

-end-

wrote:
MEDIA RELATIONS OFFICE
JET PROPULSION LABORATORY
CALIFORNIA INSTITUTE OF TECHNOLOGY
NATIONAL AERONAUTICS AND SPACE ADMINISTRATION
PASADENA, CALIFORNIA 91109. TELEPHONE (818) 354-5011
http://www.jpl.nasa.gov

Guy Webster (818) 354-6278
Jet Propulsion Laboratory, Pasadena, Calif.

News Release: 2005-072 May 6, 2005

Rover Team Tests Mars Moves on Earth

Mars rover engineers are using a testing laboratory to simulate
specific Mars surface conditions where NASA's rover Opportunity
has spun its wheels in a small dune. Careful testing is
preceding any commands for Opportunity to resume moving to get
out of the dune and continue exploring.

The rover team at NASA's Jet Propulsion Laboratory, Pasadena,
Calif., has cooked up recipes combining various sandy and
powdery materials for the best simulation on Earth of the dune
where Opportunity dug itself in to wheel-hub depth last week.
The team has not asked Opportunity to turn its wheels at all
since the rover bogged down during a drive on April 26.

"We choose to proceed cautiously, so we don't expect to begin
actually driving out of the dune before next week, possibly
later," said Jim Erickson, rover project manager at JPL. "Both
Opportunity and Spirit have already provided many more months
of scientific exploration than anyone expected. By taking good
care of them, we hope to keep them exploring for more months to
come. Tests so far have sustained our optimism about
Opportunity's ability to drive out of this dune, but we have
more testing ahead to understand how robust that capability
is."

Opportunity had driven about 40 meters (131 feet) of a planned
90-meter (295-foot) drive on the rover's 446th martian day when
its wheels began slipping. The rover was driving backwards at
the time. The team frequently alternates between backwards and
forwards driving to keep wheel lubrication well distributed.
The wheels kept rotating enough times to have covered the rest
of the distance if they hadn't been slipping, but the rover
eventually barely inched forward. After a turn at the end of
the planned drive, Opportunity sensed that it had not turned
properly and stopped moving.

Opportunity is positioned across the ridge of an elongated dune
or ripple of soft sand that is about one-third meter (one foot)
tall and 2.5 meters (8 feet) wide. "We've climbed over dozens
of ripples, but this one is different in that it seems to be a
little taller and to have a steeper slope, about 15 degrees on
part of its face," said Mark Maimone, a JPL rover mobility
engineer.

Last week, engineers arranged a simulated dune using sand that
was already at JPL's rover testing facility and put a test
rover into a comparably dug-in position. The test rover had no
difficulty driving away, even when sunk in belly-deep. However,
that sand offered better traction than the finer, looser
material that appears to make up the surface at Opportunity's
current position. "We needed to do tests using material more
like what Opportunity is in, something that has a fluffier
texture and cakes onto the wheels," said JPL rover engineer
Rick Welch, who is leading the tests.

Experimenting with different mixtures, engineers and scientists
came up with a recipe that includes play sand for children's
sandboxes, diatomaceous earth for swimming pool filters and
mortar clay powder. Then they went to several home supply and
hardware stores to find enough bags and boxes of the
ingredients to make more than 2 tons of the simulated Mars sand
for more realistic mobility tests, said JPL rover mobility
engineer Jeff Biesiadecki.

Dr. Robert Sullivan of Cornell University, Ithaca, N.Y., a
rover science team member, worked with engineers in the JPL
testbed to match the properties of the test sand as closely as
possible with those of the sand beneath Opportunity, based on
images of wheels and wheel tracks on Mars. "We found that when
the wheels dig in, the material we're using does stick to the
wheels and fills the gaps between the cleats, but it doesn't
stick when you're just driving over it. That's good because
it's the same as what we see in the images from Opportunity,"
Sullivan said.

Experiments indicate that in this more powdery material, the
test rover positioned comparably to Opportunity can drive out
after some initial wheel-spinning. More testing, analysis,
planning and review will precede any actual commands for
Opportunity to begin driving away from the dune.

Meanwhile, Opportunity has been using its cameras to study its
surroundings at the edge of a region called "Etched Terrain."
Since landing more than 15 months ago, it has driven 5.35
kilometers (3.32 miles). Spirit, halfway around Mars, has
recently been using all of its research tools to examine an
outcrop called "Methuselah," the first outcrop of layered rock
that Spirit has found. The rover has also been taking short
movies of dust-carrying whirlwinds called "dust devils." On
some afternoons, the rover sees several at once moving across
the plain. Spirit has driven a total of 4.31 kilometers (2.68
miles).

JPL, a division of the California Institute of Technology in
Pasadena, has managed NASA's Mars Exploration Rover project
since it began in 2000. Images and additional information about
the rovers and their discoveries are available on the Internet
at
http://www.nasa.gov/vision/universe/.../mer_main.html
and http://marsrovers.jpl.nasa.gov .

-end-



Dumb idea? # 0023541:

When riding a push-bike ( Australian for bicycle )up really steep hills
( like around Mount Panorama the wrong way when I studied at Charles
Sturt Uni. ), to make it easier I used to "tack" from side to side
(zig-zag ) to reduce the effective gradient to a lot less than
tackling it head on with a brute force approach.

Also, at the end of each tack when I would "come about", I would roll
down the hill slightly, and vear up suddenly in combination with a quick
acceleration to get a "slingshot" from our friend Mr. G ( or foe if you
are an apple ). This energy would help propel me up to the next
"level", ready to tack again.

However, I don't think any rover has discovered a sealed ( AKA bitumen,
asphalt, hard-top, pavement ) road at this stage.


|-] ( Open source robot smiley face )

Cheers

Dale
Cheers

wrote

Experimenting with different mixtures, engineers and scientists
came up with a recipe that includes play sand for children's
sandboxes, diatomaceous earth for swimming pool filters and
mortar clay powder. Then they went to several home supply and
hardware stores to find enough bags and boxes of the
ingredients to make more than 2 tons of the simulated Mars sand
for more realistic mobility tests, said JPL rover mobility
engineer Jeff Biesiadecki.

Presumably they included in the play sand, the inevitable cat mess?

Jack

It looks like the treads are getting a bit bare...

http://www.lyle.org/mars/imagery/1P1...5R6M1.JPG.html

see also

http://www.lyle.org/mars/image=ADry/...M1=AD.JPG.html

http://www.lyle.org/mars/image=ADry/...M1=AD.JPG.html


http://www.lyle.org/mars/imagery/1F1...4L0M1.JPG.html


Michael

wrote:

It looks like the treads are getting a bit bare...

They are solid clete, which have become filled with
very fine dust, like flour. That caused a lose of
traction. We just may be stuck here for the long term.

Can sample grabbers be used for leverage?
Use one of the arms to push off of sand.

Rich

wrote in message
oups.com...
Can sample grabbers be used for leverage?
Use one of the arms to push off of sand.

Rich

LMAO!!

wrote in message
oups.com...

Can sample grabbers be used for leverage?

Perhaps. If it had them.

Use one of the arms to push off of sand.

It only has one arm - and that one is way too fragile.

They are solid clete, which have become filled with
very fine dust, like flour.

Hi David,

Not to be difficult but what is clete and if it is solid clete, how has
it become filled with dust?

Best,

Michael

wrote in message
oups.com...
They are solid clete, which have become filled with
very fine dust, like flour.

Hi David,

Not to be difficult but what is clete and if it is solid clete, how has
it become filled with dust?

Best,

Michael

The answer is simple. The "dust" is damp, and only the outer surface,
when warmed and exposed to the thin air, is dry. Look at the videos they
have been showing on the news. The cleats on the earthbound model shed the
soil immediately. The cleats on the rover on Mars stay packed. Moisture
and lower gravitation are the reasons. Look at my page detailing the
problem here.

http://xenotechresearch.com/wetnow02.htm

Bottom line- until they admit that Mars has liquid water and they take
that fact into account, they will not be able to properly simulate and
defeat the problem.

Cheers!

Sir Charles W. Shults III, K. B. B.
Xenotech Research
321-206-1840