How can I get
involved?
There are three
possible paths to getting involved with the Red Rover
Project:
"Earth"
Configuration
Using the freely distributable "Earth
site" software (available from the Planetary Society), you can remotely control any
currently-existing Red Rover terrain site which
is connected to the Internet. You will need only
a Pentium-class PC and an Internet connection.
Note that there is a significant delay in sending
commands to a rover via the Internet — just like
the real thing!
"Mars"
Configuration
The full Red Rover software is available from the
Planetary Society or from suppliers such as Pitsco. It costs approximately $200 at
the time of this writing. In addition, you will
need:
– A Pentium-class PC with USB and serial ports
– Logitech Quick-Cam Express Web Camera (or
equivalent)
– LEGO Mindstroms Robotic Invention Set
The camera can be obtained for as little as $50
— an expensive camera is not necessary! The LEGO
Mindstorms set will cost approximately $200.
Pitsco sells a similar LEGO set for about the
same price.
LEGO
"Mars Explorer" Configuration
This is essentially the same software as the Red
Rover software, but lacks the Internet capability
(you won’t be able to drive remote rovers nor
will other people be able to drive yours). The
equipment needed is the same as for the Mars
Configuration above, simply substituting the $50
LEGO Mars Explorer kit for the $200 Red Rover
kit. Note that you are technically not part of
the Red Rover Project if you go this route.
Terrain
Construction 101
Here are some tips
for constructing a realistic Mars terrain. Remember, the
student sees whatever the rover camera sees — the more
realistic the terrain, the more realistic the experience!
Take a look at the Photo Gallery for some ideas.
Research
the site! Don’t just throw some rocks on
a board and call it done! There are plenty of
Mars images available to look at. If you use
Woodland Scenics Mold-A-Scene plaster, you can
actually duplicate the rocks you see in the
images. Learn some basic Martian geology so that
you can make a scientifically valid terrain.
Construct
your terrain using HO model railroad techniques. Model
railroad construction is a lot easier than you
would think and everything cleans up with water.
You can get amazingly good results. Most hobby
shops have some excellent books that cover
everything you need to know. I strongly recommend
Woodland Scenics products. I don’t work for
Woodland Scenics, nor do I get a cut in their
profits, but I have tried several other comanies
and none were even close to the results I got
from Woodland Scenics products. Your milage may
vary…
Mold
rocks from plaster. Rock molds are
readily availble and give great results. You can
use real rocks, provided they can be made to look
"Martian", but this isn’t easy. The
plaster rocks can be stained with Woodland
Scenics Burnt Umber pigment and will look great.
Mars
soil simulant is available from Johnson Space
Center. This is the real stuff — what
they use to experiment with real rovers. It has
basically the same composition and texture as
Martian soil. If you can’t get this, you can use
Woodland Scenics medium and fine iron oxide
ballast. Mix it up in a shaker, spray cement on
the terrain and dust with the ballast. Looks
great!
Construct
the terrain on a rigid 5′ x 5′ board.
Much larger than this become unwieldy very
quickly. You may want to consider using 4′ x 4′
since most wood comes in 4′ x 8′ sheets. I find
this to be a little cramped, though. I used two
overlapping 4′ x 5′ boards wood-glued together to
make our terrains.
Build
elevated terrain using newspaper and plaster
cloth. You can build canyon walls by
balling up newspaper into a 2" flattened
ball and stacking them 3-4 high. Use masking tape
to hold the balls in place. Dip the plaster cloth
(a cloth mesh impregnated with paster) in water
and lay it over the newpaper balls. The cloth
will harden to a rigid shells. Use two layers for
added strength. Stain the result with burnt umber
pigment. The results are startling!
Craters
and unusual rocks can be made from Mold-A-Scene
plaster. Woodland Scenics makes a
plaster that forms a putty you can mold with your
hands. Shape it into craters and custom rocks. It
is a little crumbly, but that’s actually good for
cratered terrain.
Attach
all rocks and ballast with Woodland Scenics Spray
Cement. White glue supposedly works, but
I have never had any luck with it. the spray
cement is much better. After you sprinkle on the
soil (ballast), spray it again with the cement to
help hold it in place.
Use
Mars Pathfinder images to make your
"horizon". Or, paint a
"night-time scene", but this doesn’t
give the illusion of distance in the camera that
the images do.
Mount
terrain boards in cabinets or on tables.
But make sure you can still access the boards for
maintenance!
Use
plexiglass to keep out "little
fingers". We have a continuing
problem with kids (and some not-kids)
disassembling our rovers. A little plexiglass
goes a long way…
Suspend
cables using the "Sally Technique".
Named for my lovely wife who put an end to two
months of stress by coming up with a way to
suspend the cables off the board in such a way
that they don’t tangle. Use two pieces of black
elastic. Tie one to the ceiling near the back
left corner of the board. Tie the other end to
the cables so that they hang about 12" above
the board. Tie the other piece of elastic to the
ceiling near the center of the board. Tie the
other end to the cables so they too hang about
12" above the board. The rover will be free
to travel the entire board and the cables won’t
tangle! A rather grainy picture of the cables is
in the Photo Gallery.
Rover
Construction 101
You will need to
experiment with rover designs, but here is what I’ve
found works well:
Use
gear-reduction motors! Real rovers
aren’t dune buggies! These rovers should move
pretty slow, but have a lot of power for terrain
climbing.
Ensure
a stable mount for the camera. There is
a LEGO connector piece that can be glued into the
Logitech camera "ball" which will allow
it to attach securely.
Use
the sensors! The software has the
capability to receive data from a light and touch
sensor as well as from the camera. this can
significantly enhance the science you can do.
Use
a third motor if possible. The RCX brick
(the control for the rover) has three inputs and
three outputs. You can use that third output to
drive a robot arm, a rotating platform for the
camera, or something for a "lander".
Superglue
that sucker! But only after you are sure
you’re happy with the design, of course. Spend a
month or two testing first.
Don’t
put the RCX brick on the rover. Yes, I
know the Planetary Society says to do this, but
you’ll get nothing but trouble. The rover will
move out of range of the IR tower and get stuck
and the RCX brick will make the rover top-heavy
and unstable. You have to have the camera cable
anyway, so you don’t gain anything by getting rid
of the LEGO cables.
Construction
Costs
Here
is a link to an Adobe Acrobat document that tracks
everything we’ve spent on our system. Keep in mind that
our computers and the cabinets were donated, so this is
only the expenses for the rovers and terrains themselves.
Good luck!
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