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View Full Version : NASA rover uses BASIC Stamp



Tracy Allen
02-09-2005, 02:02 AM
The "tumbleweed" rover is a 5 foot inflated ball that is blown around by the wind and relays its position and environmental data to the base station via satellite. One is currently deployed near the south pole of Antartica and the data is on line for us to see (That is, if they get the satellite link back up and running). Here is the link...

robotics.jpl.nasa.gov/~behar/southpoletw.htm#_1/2004:_South_Pole, (http://robotics.jpl.nasa.gov/~behar/southpoletw.htm#_1/2004:_South_Pole,)

If you look near the bottom of that page, you can click on the image of the circuit board and see the BS2p40 module, the sensirion tempeerature/humidity module, the acceleromeer, the air pump, etc etc.

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Tracy Allen
www.emesystems.com (http://www.emesystems.com)

Gadgetman
02-09-2005, 02:51 AM
Interesting.

But I wonder about the design, though....

Why are they using Ni-mh rechargeables on a 'one-shot' system?

Not only won't these things get near any chargers once they are released, but how well does Ni-mhs tackle cold weather?
They're not the best choice when it comes to power/weight ratios, either.

Nice to see a BS2 in action, though. http://forums.parallax.com/images/smilies/smile.gif

Buck Rogers
02-09-2005, 03:20 AM
Hello from Buck Rogers

I don't know. For what they are doing it makes sense. Sort of. Especially since the Poles match the perfect examples of what to find on Mars. What the things find wandering around will enable the agency to build better sats for exploring Mars.

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Buck Rogers

www.gregg.levine.name (http://www.gregg.levine.name)

achilles03
02-09-2005, 10:24 AM
I think the NiMH are for high current applications... (maybe when the air pump turns on?). It looks like Lithium's are the primary battery. Lithiums have a much higher capacity, but aren't good at high current drains... so by combining the two, you get the best of both worlds.

Also, NiMH's are better than alkaline's at low temp.

Dave

upand_at_them
02-09-2005, 11:21 AM
NiCds would be a mistake. But NiMH are good down to -20C, I think.

Mike

Ken Gracey
02-09-2005, 12:56 PM
Page 3 of this document explains how the BASIC Stamp is used in the Tumbleweed:

http://robotics.jpl.nasa.gov/~behar/southpoletw_files/IEEEAeroConf2004TumbleweedBehar.doc

Ken Gracey

Ernie
02-10-2005, 12:00 AM
Rechargables make sense if you factor in the time to test the instrument before deployment.

You really don't want to take it apart after you're done testing it to replace the batteries, cause after you reassemble it you'll need to test it again. Then take it apart to replace the batteries...

Rechargables let you top off the cells right up till deployment.

Tracy Allen
02-10-2005, 01:37 AM
If the temperature warms up above zero C inside the globe, one could imagine an NiMH recharging circuit based on a combination of solar power and a generator coupled to the tumbling action. This is government work, though, and they have to consider these devices disposable. They never did recover the one in Greenland, it says. Maybe it fell into a crevass?

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Tracy Allen
www.emesystems.com (http://www.emesystems.com)

Gadgetman
02-10-2005, 03:29 AM
Maybe they could use tumbling, but not solar panels.

Solar panels are just too fragile.
(Either that or too heavy)

As for tumbling...
The only system I could imagine is something like the Seiko 'kinetic' system, which is a small weighted fly-wheel, but the weight and size of the fly-wheel dictates the max amount of power you can get out of it.
I wonder if anyone sells parts that can be used like that?
(I like to tinker, and I could use a powersource like that in my cayak... http://forums.parallax.com/images/smilies/smile.gif

As for disassembling it to replace cells...
And you wouldn't need to do that to recharge them?

allanlane5
02-10-2005, 03:46 AM
I agree the NiMH are to supply short-term, large current power. They are then probably recharged from the Lithium's. In some of the material, the NiMH are not mentioned at all -- which says to me that they found some power problem using Lithiums by themselves, and used the NiMH to solve it.

High-current needs -- the air-pump motor, probably the Iridium transmitter. (And isn't it cool, after all this time and Motorola's "failure", that the Iridium system is still up and running! It's really the only way to talk to the poles.)

Buck Rogers
02-10-2005, 04:08 AM
Hello from Buck Rogers

Regarding the Iridium transmitter, Motorola didn't fail on them. The company itself did. They failed to have Motorola include a cellphone as part of the design. In fact I suspect the designers at Motorola are, or were, at fault.



But yes, your right they are the only way to communicate with the poles, when it comes to hardware working up there.

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Buck Rogers

www.gregg.levine.name (http://www.gregg.levine.name)

John Kauffman
02-10-2005, 10:49 AM
I recently bought a few flashlights with built-in chargers from our hardware store.

Shake them for 30 seconds (a weight slides up and down in side the handle) and they power a blue LED for a minutes or so. It is bright enough to read. Weight is about 400grm.


lrohn
02-12-2005, 05:16 PM
That weight is a very strong magnet and it slides through a coil. Every time it does this it energizes the coil which charges a capacitor that powers the LEDS. http://forums.parallax.com/images/smilies/tongue.gif

Phil Pilgrim (PhiPi)
10-21-2010, 08:17 AM
This thread dates back five years, so I guess it's old news. But I just saw a segment about the Tumbleweed tonight on the History Channel. It didn't take more than the brief glimpse they offered of its instrumentation package to recognize the BS2p40!

-Phil

Campeck
10-21-2010, 01:23 PM
I can't find any pictures of anything on the NASA site. What gives?

Phil Pilgrim (PhiPi)
10-21-2010, 08:21 PM
I can't find any pictures of anything on the NASA site. What gives?
Those NASA links are more than five years old. Web pages can change in five years.

-Phil

Campeck
10-21-2010, 09:16 PM
yeah well they shouldn't!
haha. Does anyone have a working link to the picture? google didn't turn up anything either.

Man if NASA is using BS's then what am I doing fixing projectors? I want to program space robots...(really...that is my career goal. I need to go back to school...lol)