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Moon Shot - Ground Equipment Section

Posted: Mon Sep 27, 2010 7:24 pm
by joertexas
This section is for the equipment that doesn't actually fly - the lander and orbiter will each have their own section.

I've been researching different methods of communicating with the backhoe while it's in the craters. Cabling is too heavy, whether wire or fiber optic, since the bottom of Hinshelwood is about 10km from the ridge. So, I think we're down to radio communications using either the comms rover or the orbiter to relay as needed.

JR

Backhoe Operations

Posted: Tue Sep 28, 2010 2:54 pm
by joertexas
Another issue regarding cabling was the ability to power the backhoe while it is working in the craters. The mass budget allows for another two or three 54Ah battery packs, each of which will allow the backhoe to operate for an hour to two hours, depending on the power levels at the time. Added to the three packs in the original design, the backhoe should be able to run for at least six hours.

Given that the crater wall into Henshelwood is about a 12-15% grade, the backhoe should be able to travel up 5km/hr, once a route is scouted and cleared for it to the bottom. A minimum of six hours operating time should allow an hour or so of exploration time at the bottom of the crater before the backhoe would have to return for recharging.

Testing for Water

Posted: Tue Sep 28, 2010 3:07 pm
by joertexas
As it turns out, there are two very simple, reversible methods to detect the presence of water:

If water vapor come in contact with anhydrous copper (II) sulfate, it will change the color of the crystals from white to blue. If the crystals are heated and dried, they change color back to white as the water vaporizes away. Blue cobalt chloride paper behaves in a similar manner, turning pink when water is present.

The next question for all you chemists out there is how these substances behave in a vacuum. If the test chamber has to be pressurized, that adds a level of complexity to the water test unit.

JR

Communications

Posted: Tue Sep 28, 2010 8:28 pm
by joertexas
This is a good article on communicating with the rovers..

http://citeseerx.ist.psu.edu/viewdoc/do ... 1&type=pdf

JR

multi functionality

Posted: Thu Mar 15, 2012 7:39 am
by Engineer
Have you considered using your camera rovers as relays? you've got a sat, the relay rovers, and the main rover. should be able to make a good line of site with all of that.
:cool:

Posted: Thu Mar 15, 2012 5:28 pm
by joertexas
[quote=""Engineer817""]Have you considered using your camera rovers as relays? you've got a sat, the relay rovers, and the main rover. should be able to make a good line of site with all of that.
:cool: [/quote]

Yes, but the transceiver I found weighs 3.2kg. The whole rover is 5kg. I don't know if there's a space rated transceiver small and light enough to do the trick, and power consumption is an issue, too.

JR

Posted: Thu Mar 15, 2012 7:32 pm
by RaresH
Well, if you can't find a tranciever light enough, then take an existing design and build one using the lightest materials out there. Baytubes could be ideal for weight and conductivity.

Posted: Fri Mar 16, 2012 4:06 am
by joertexas
[quote=""RaresH""]Well, if you can't find a tranciever light enough, then take an existing design and build one using the lightest materials out there. Baytubes could be ideal for weight and conductivity.[/quote]

We have to be careful about using custom equipment, because everything we launch has to be space rated - which mostly means radiation hardened. I'd imagine that someone has a lighter, shorter ranged unit we can use. If not, then we'd have to have them built and certified.

JR

Posted: Fri Mar 16, 2012 6:30 pm
by stevend
I can see it having to be radiation hardened, and avoiding interference with other's satellites and lunar surface communication equipment but certified? Is there some lunar government that regulates communication equipment on the moon? What do you mean by certified?
-Steve

***looks down list***We're missing a screw for that micro-controller brace

Posted: Fri Mar 16, 2012 7:00 pm
by Engineer
Probably certified to work. I'd suggest that if you haven't already, take a computer engineering lab. you'll find that most electronics and products come with a DATA sheet. you can find lowest operation temperature, highest maximum voltage ratings, all that jazz. http://search.digikey.com/us/en/cat/rf- ... ransmitter go ahead and wet your appetite. Equipment is now cheap and easy to come by. and the documentation on them are great.
:cool: