NASA to Demonstrate Moon Rover

coondoggie writes "NASA will this week demonstrate its lunar robot rover equipped with a drill designed to find water and oxygen-rich soil on the moon. NASA said the engineering challenge of building such as drilling system was daunting because a robot rover designed for prospecting within lunar craters has to operate in continual darkness at extremely cold temperatures with little power. The moon has one-sixth the gravity of Earth, so a lightweight rover will have a difficult job resisting drilling forces and remaining stable.The project is just one demonstration of the collaboration NASA is utilizing to bring together its next moon shot. For example, Carnegie Mellon was responsible for the robot's design and testing, and the Northern Centre for Advanced Technology built the drilling system. NASA's Glenn Research Center contributed the rover's power management system. NASA's Ames Research Center built a system that navigates the rover in the dark. The Canadian Space Agency funded a Neptec camera that builds three-dimensional images of terrain using laser light, NASA said."

drill problems

[Jodka]

quote:

...so a lightweight rover will have a difficult job resisting drilling forces and remaining stable

I assume here they are referring to either: 1) The problem of the drill staying still and the rover rotating around it. 2) Downward force on the drill lifting the rover up.

With conventional earth-bound drilling these problem are solved in the case of 1: by using multiple counter-rotating bits and in the case of 2: Auger bits, which both remove material and bite into the material at the bottom of the hole with a screw, pulling themselves downward without requiring downward pressure on the drill.

I would certainly think that counter-rotating heads would work on the moon, though use of an auger might depend on the material properties of moon rock.

Re:Less gravity

[meringuoid]

I think that with the moon's lower gravity you could get away with hauling much more weight in batteries.

Look up the cost of shipping a kilo of mass to the Moon before you say that. Every kilo used up by a battery adds to the launch cost, and is a kilo not used up by a scientific instrument. And there's a hard upper limit: there are no Saturn-class launchers in the world today, so the whole payload cannot exceed the capacity of the largest Delta Heavy in the inventory.

Internal Combustion

[StCredZero]

It's hard to beat the energy & power density of internal combustion engines. Since there is no air, your propellant is heavier, since you'd need to carry the oxidizer, but I suspect that you'd still have an advantage in range. In The Case for Mars [amazon.com] Robert Zubrin has proposed internal combustion Mars rovers that could use CO2 as an oxidizer. (I forget what the fuel is, but it can be made from methane derived from local CO2 and hydrogen.) Also, in the book The Rocket Company [hobbyspace.com] an automaker funds a trip to the moon where they use a modified SUV carrying its own oxidizer.

Re:Sigh...

[rickb928]

Absolutely...

Since helicopters use atmospheric resistance to maneuver, those tactics don't apply to the Moon, with virtually no atmosphere to use for the tail rotor to counteract tourque. Bzzzt! Wrong answer!

Firing pitons into the Moon to hold the rover down for drilling makes sense except for two points:

- Drilling operations will be limited by how many pitons you carry, and how the firing mechanism works. This also adds weight and defeats the 'lightweight' requirement.

- the mechanism to fire a piton, hold onto it, and then let go adds too much complexity. Not good.

Now you know we you and I aren't working on this project.

I might think the auger idea works, but will the auger bite into rock? What happens with loose debris?

And I have no doubt that a clever drill design will come up. Probably a combination of auger and slow-speed drilling, with more time taken instead of trying to do it too quickly and bouncing the rover around.

Then again, they could lock a wheel and drag it around like a trenching tool.. works on Mars....