The Planetary Society Blog

Even houseflies have evolved the ability to brush themselves clean. Actually they do not need special tools for that (except perhaps a few strategically placed hairs); they just have enough versatilty in their legs, and the appropriate logic in their nervous systems. Hopefully future robot craft too will have limbs designed for general rather than specific tasks; versatile enough to fix unexpected problems --- dust off a solar panel, dig a wheel out of a sandpit, ...

Hopefully the next generation of rovers won't have to depend on the Sun but use long lasting nuclear power to speed up the exploration ;)

They didn't really expect it to last long enough to need a brush.

Opportunity sure has been needing a long rest after that long trek she accomplished, that was once thought impossible for this little rover. I believe she has earned it. Then it's off to some hill climbing at Cape Tribulation! :)

They didn't _really_ expect it to last, perhaps. Because most other contingencies would be planned for, no?

But as it doesn't kill the old girl, I guess the absence of a panel brush isn't much to grouch about.

Never mind, I checked and the rover arm is situated under the panels, no reach there. So what could they have done, really?

It would indeed have been nice to have a wiper of some sort. But it would have been another mechanism, with a controller and power supply. It would need to be pretty well tested to make sure it did more good than harm. You might be able to make something for $10M additional, but it could easily be more. Power wouldn't be an issue, since it's only used sporadically, but the mass would kill you; you'd need at least 3 kg for the whole system. Might as well ask for a pony while you're at it.

Now, the idea of a general-purpose arm that could be used to remove dust does sound great for future missions, because it would be useful for lots of things. The extra resources needed to ensure it could reach anywhere on the rover would be small if the requirement went in early in the design.

Okay, I'll stop designing it in my head now. I don't even live in California...

The best thing to use for dust removal and rejection, is something that does not involve moving parts, not complex, requires little or no power, and very light weight. Wipers to dust the rover off is not a good idea, for one, it is a moving part. Also, the martian dust is very possibly abrasive, and when you try to brush the cells, you can risk scratching or damaging the cells. About the best idea that I have heard floating around, is to use some sort of anti-static coating (because most of it, is magneticly attracted). The JPL developed Nano rover that was developed for the hayabusa mission to an asteroid, but was never never flown on that mission, was to utilize a noval electrostatic dust rejection system. That might be the best approach for larger scale rovers on Mars. Or just use a bigger solar array, with the cost of just the added weight.

They should have added a few cans of air or just a fan.....

That's an impressive amount of dust on the panels. Will winds eventually blow some of it off? Or have they already and this is the residue? And how to they keep the camera lens clean? It surely doesn't look like the solar panels.

The rovers were exploratory vehicles. They weren't the first attempt to explore the Red Planet robotically. You can't spend the extra bucks for something that may not make it there in the 1st place. There were several failed attempts before Spirit and Opportunity landed. There have been several failed attempts since then, as well. The winds on Mars seemed like a great idea for panel cleaners (and they were for several years. I am sure that the new rover will have some way to clean the solar panels. SP's are far more cost-effective than any nuclear power plants for robotic rovers.