Why not just have a brush on an arm?
To dust off the solar panels?
NASA's ageing Mars exploration rover Opportunity is heading for Greeley Haven for the winter - a site with a sun-facing slope to catch the meagre rays of our star on its solar panels. False colour image of Greeley Haven False colour image of Greeley Haven taken by Opportunity. Credit: NASA/JPL-Caltech/Cornell/Arizona State Univ …
To dust off the solar panels?
1. The arm won't reach them.
2. The arm does not have a brush.
3. The panels are delicate - trying to use the arm to brush them would probably damage the panels.
..they weren't ever expected to survive that long to need one?!
If my wife was in charge of driving the rover she would swing it around a few corners and get rid of the dust. I often say to her that her tyres never get worn in the middle.
Why not bolt a brush onto the new one so it can go and clean the old one?
Why are the solar panels to delicate tho, the ones people strap to their house aren't, obviously the ones on the mars rover are far advanced, but can they not put a protective cover on them?
Beaten me to it :)
I would guess that the cost to develop and test such a system could not be justified for a mission that was intended to last no more than 90 Sols.
There's also the weight penalty to factor in as well, the solar panel cleaning system would probably have meant that a science experiment would have to be left out.
They have to be robust to survive being launched into space on a rocket, I think the dust and the weakening batteries would cause more of an issue where less daylight means more chance of the batteries being depleated.
Quite possibly, but after 8 years there's no longer any warranty conditions to worry about.
i'm guessing it's an issue of weight and size (for it to be launched from Earth).
Now, if it had been made in space on a space station where they could send up components and build/launch it there...
(if you will excuse the pun) http://xkcd.com/695/ Also time to note how uncommonly dusty it is in here today. Really making my eyes water ...
Supposed to last about 3 months, and one of them is still up for the challenge almost 8 years later!
Imagine if the Rovers' construction had been outsourced....
Just think about if Crapita had got their dirty little mitts on the contract! Over priced, delayed and would probably not even survive a few days let alone the spec'd 3 months
Coat please - the one with the insatiably large Crapita beating stick poking out of the pocket. Yes, it is the one with the large anti-Crapita logo on the back.
"Supposed to last about 3 months, and one of them is still up for the challenge almost 8 years later! Imagine if the Rovers' construction had been outsourced...."
You say that, but if NASA had built it to last *only* the spec'ed 3 months, it'd have been a heck of a lot cheaper...
Still, impressive that you managed to get a jibe in about outsourcing in this story!
"You say that, but if NASA had built it to last *only* the spec'ed 3 months, it'd have been a heck of a lot cheaper..."
Yeah, but think of the 'added value' NASA got for not spoiling the ship for an ha'porth of tar....
... but where's a squeegee-guy when you need one?
Obviously he is waiting at the next set of traffic lights...
Now granted I'm no NASA scientist, nor am I a robot building genius, so there may well be a reason behind this... but surely if a layer of dust coving the solar cells is such an issue, can a wiperblade/wiperbrush not be employed to give them a quick swish from time to time? Sure, they will use a tiny bit of power, but will they use less than the loss due to the dust? Can't see how they need to be especially heavy and/or complex. Or am I missing something?
Uhh, yeah. The first six comments on this article.
But it seems by the time the moderator allows the comments to be displayed, other comments may have appeared higher in the list. Bah.
The designers of the Opportunity Mars Rover tried to reduce the effects of dust by making Opportunity's panels larger than they needed to be. This combined with providential winds when needed has kept Opportunity going.
Electrostatic cleaning may be considered for future mars missions. Here is a link
Note that the Curiosity Mars Rover currently headed for Mars has a nuclear power source and so needs no such technology.
You know the drill.
You stop at the lights.
Some yob comes over and proceeds to 'wash' your windscreen.
Is there no unemployment on Mars?
Are there no traffic lights?
...No retirement either though
I'm surprised that nobody else noticed the top right corner of the property - beachfront property on Mars???
Of course, I meant 'top right corner of the PHOTO'
Must... Have... Coffee
Greeley Haven looks much nicer in the brochure.
... a lower than usual number of caravans on arrival.
we had a camp site next to some punk rock aficionados from Venus who played the Sex Pistols all night. I haven't seen the missus since.
Install a small air compressor. The rover can top off the air tank while the sunlight is still bright (relatively speaking) and then dust off the panels later.
So we add a compressor and air tank to the rover.
Then we need to increase the size of the descent parachute, air bags, and rockets to handle the extra weight of the compressor and air tank.
Then we need to increase the size of the aeroshell to accommodate the extra size of the descent parachute, air bags, descent rockets, compressor, and air tank.
Then we need to increase the size of the orbital insertion thrusters to accommodate the extra mass of the aeroshell, descent parachute, air bags, descent rockets, compressor, and air tank.
Then we need to increase the size of the Earth to Mars orbital insertion rockets to accommodate the extra size of the orbital insertion thrusters, aeroshell, descent parachute, air bags, descent rockets, compressor, and air tank.
Then we need to increase the size of the upper stage booster rocket to accommodate the extra size of the Earth to Mars orbital insertion rockets, orbital insertion thrusters, aeroshell, descent parachute, air bags, descent rockets, compressor, and air tank.
Then we need to increase thee size of the first stage to accommodate the extra size of the upper stage booster rocket, Earth to Mars orbital insertion rockets, orbital insertion thrusters, aeroshell, descent parachute, air bags, descent rockets, compressor, and air tank - and we don't have a booster that big, so sorry, you cannot go to Mars.
Or, we can accept that the panels will get dirty at some point, and get the best science we can during the time we have.
Sing it with me:
Every kilo's sacred.
Every kilo's great.
If a kilo's wasted,
NASA gets irate.
It's false colour, but it makes the moon look like it's made of copper sulphate.
Rain-X works great on my windshield and weighs very little :)
but couldn't they just add a couple of gears to the motor that extends the solar panels and have the panels flap, like a mother bird does when settling in her nest, after the dusty season?
They must have already created the rover such that geometrically, the objects won't settle on its panels. Think about typical roof of a typical house, like this: ^
But then it could be that it refracts the rays of light. But then again, they could have created panels and structured it such that it traps the rays. Think about hexagonal structure that is made of reflectors that would eventually focus rays.
You could imagine such and such, but you never know what you don't know - you can't plan for everything. That is, once you see how your current iteration, i-th, fails, you can start elaborating on i+1'th. But you can't really start thinking about i+2 at i'th step. Sorry. No.