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[on:]

Well, I'd like to... What would it take to space harden an AVR? Or do space hardened AVRs exist already?

If I had to use a PIC or some other microcontroller I would, but I don't think there are any space hardened PICs either.

Basically the main things it would have to deal with, as far as I can tell, is a massive amount of radiation and lack of convection for cooling.

The cooling would be simple enough, just attach every single thing to a heatsink (probably including passive devices like resistors and capacitors). Another cooling idea I had was, if it didn't add too much weight, some kind of fluid cooling. The problem there, of course, is freezing (space is a place of extremes, the melting and boiling temperature of things tend to be very close together in such an environment).

The radiation is much harder to deal with. Some could be minimized by putting the major electronics in a Faraday cage. However that wouldn't stop everything. A magnetic field would work but would probably be too electrically expensive. Embedding it in three feet of lead would also work but that would be too heavy to get into orbit.

What I want is to be able to build a cheap robot with a camera that could go to the Moon or Mars and wander around taking pictures, the Moon would be preferable. My dinky little webcam that I got for $12 has far better picture quality than the expensive cameras they brought with them during Apollo. There hasn't been a single picture taken from the surface of the moon in almost 40 years.

My conclusion so far has been that the reason space-based robots tend to be extremely expensive (in the range of billions of dollars) has less to do with what they make them out of than how much it costs to get there. In other words if it costs on the order of trillions to get there then it doesn't really matter if you're spending $1000 on your robot or $10 billion, it's such a tiny part of the overall cost anyway, might as well make it worth it.

My approach is to figure out if it's even possible for me to build a robot that will work there, then figure out the cheapest way to get it there.

I know people have put Arduinos on high altitude balloons, but they're still in the Earth's magnetosphere (unless they were near the poles) and so wouldn't have to deal with radiation as much.

[Reply #1 on:]

What I want is to be able to build a cheap robot with a camera that could go to the Moon or Mars and wander around taking pictures, the Moon would be preferable. My dinky little webcam that I got for $12 has far better picture quality than the expensive cameras they brought with them during Apollo.

Cooling wouldn't be a problem for an Arduino or other devices running around on the moon. Getting too cold would be a more likely scenario.

How would you get your robot to the moon? Drop it off on your next trip?

How would you get any pictures from your webcam sent back to where you could see them? The Arduino does not have the computing power or memory to do image capture or handle streaming video.

How would you transmit the image data back to earth?

How would you power your robot? Batteries don't work all that well when they are cold, and it's pretty cold on the moon. Solar might work. There's plenty of sunlight on one side. Not much on the other side, though.

There hasn't been a single picture taken from the surface of the moon in almost 40 years.

I don't image much has changed. The old neighborhood probably looks pretty much the same.

Not to rain on your parade, because I like your thinking, but there are problems that need to be addressed.

[Reply #2 on:]

Cooling would be a problem because there is no air to take the heat away so much of it just stays in the object which heats up. Even though the chip doesn't get hot here on earth doesn't mean it doesn't generate any heat. The little heat it generates would build up. The air has convection because when the air gets warmer it gets lighter and is replaced with cooler air.

As I said, at the moment I'm not concerned with how I'm getting there. First I have to determine whether I have something I want there, like a robot. If I can't build the robot then there's no point discussing how to get it there.

Radio signals can be heard from quite a distance, like Voyager 1, for example. I'm sure I could cook up some kinda fancy interpolated broadband signal, given the time. Alternatively 9600 baud over shortwave wouldn't be too bad. Lasers could be another option.

Power would be a hurdle, for sure. More than just storage, though, generation too. How large would solar panels have to be? How many batteries would I need if I didn't run it in the dark for too long? It would be nice to be able to run it a little when the sun isn't shining so I could take pictures without any glare. Also it would be good if it didn't get stuck in a crater's shadow while two feet away is bright sunlight. Obviously I wouldn't be able to run it much during the 15-day night...

No, the scenery hasn't changed, but what we can record it with has. And besides, millions of people have seen Niagra falls, does that mean you shouldn't go? I want to go there as a tourist. I want to climb on the Apollo junk they left behind. I want to see if those cars still work and drive them around. I want to go where the people couldn't because they had to stay near the ship. It would be nice to be in the running for the Lunar X Prize, but I doubt I could do it before anyone else.

Obviously there are problems to be addressed, that's why I'm asking. ;D It's not like this is the final stage and, oh geeze, I forgot the rocket! In order to address the problems you must first find out what they are.

[Reply #3 on:]

Radio signals can be heard from quite a distance, like Voyager 1, for example.

What frequency does Voyager transmit on? Can you transmit on that frequency?

[Reply #4 on:]

Not to burst your bubble, but you're not going to get a robot into orbit, let alone the moon. There is a reason why space is expensive - it's difficult to get there.

The first problem you have is not electrical, or mechanical. It's financial. Once you've scraped together £500 million or so, then you and your team can make a start.

For any kind of space arduino related project, you're looking at a weather balloon with a package attached. You'll need some insulation but these projects are easily within reach.

[Reply #5 on:]

Crook, there's an excellent program for some academics called "CubeSat."  It takes advantage of the fact that many rockets have little gaps between their usual big expensive payloads, and if you can wedge a little extra lightweight box in the gaps, they can be launched almost free (relatively).

http://en.wikipedia.org/wiki/CubeSat

A CubeSat is a type of miniaturized satellite for space research that usually has a volume of exactly one liter (10 cm cube), weighs no more than one kilogram, and typically uses commercial off-the-shelf electronics components. Beginning in 1999, California Polytechnic State University (CalPoly) and Stanford University developed the CubeSat specifications to help universities worldwide to perform space science and exploration.

Generally, the hardware seems to be more like Mini-ITX motherboards, not like Arduino scale microcontrollers, but there'd be no reason to avoid Arduino if it does what you need inside that one-liter box.

[Reply #6 on:]

I have a simple question regarding your reasoning about cooling.
You say that cooling the micro-controller would be a major issue, because there is "no air to take the heat away so much of it just stays in the object which heats up". So why then attaching anything to the object (heat sink) would change the situation at all? Any why, in the case of fluid cooling, the fluid would freeze, but the micro-controller would just build up heat?

[Reply #7 on:]

And if he has a spare 40 thousand dollars or so he can launch with cubesat, into a tumbling low earth orbit. This isn't the moon. The moon would cost hundreds of millions to reach, and anything that goes there will NOT be offering piggyback rides.

Space isn't impossible, but the farther out you go, the less likely it is and the more costly.

Space and back by balloon = £500
Space low orbit = £30000
The moon = £500 million
Mars = £0.5 - £1 billion

It's just not achievable by private enthusiasts, certainly ones who ask about the basics here. Lofty goals are admirable, but we shouldn't sit here and investigate the possibility of sending a lander to the moon using an arduino, because it isn't possible.

[Reply #8 on:]

Didnt the Lunar lander only have 74kb of memory and 4kb of "RAM"?

Only people who try succeed, what if someone told Edison the bulb would never work?  Or told Elisha Gray the phone was nothing but a dream.

Im not saying its going to be easy but I see no reason why it could not be done.

[Reply #9 on:]

Well practical issues aside, there was at least one micro chip that had inherent radiation resistance, the RCA 1802. I think it might even still be in low volume production or at least available.

http://en.wikipedia.org/wiki/RCA_1802

Lefty

[Reply #10 on:]

Ham radio people have been putting amateur satellites in space for several decades. Check this out, I am sure there is a lot info  http://www.amsat.org/

The cooling is a problem, I know some people that used to work with amateur weather balloons up to about 100,000 feet. They also had cooling problems even though the temperature gets to about -30.

Mark

[Reply #11 on:]

The lunar lander was exceptionally weak on computation, most calculators these days would beat it. But also, the project cost about $2 billion in todays money. These things can't be ignored.

Edison was working with cheap materials, over and over. He was also a horrible backstabbing liar, which helped in the business world somewhat, as Tesla found out to his cost.

As far as shielding or heat goes, there are ways to remove it. Radiating it away is usually a good option, to compensate for the lack of convective cooling.

[Reply #12 on:]

My approach is to figure out if it's even possible for me to build a robot that will work there, then figure out the cheapest way to get it there.

I know people have put Arduinos on high altitude balloons, but they're still in the Earth's magnetosphere (unless they were near the poles) and so wouldn't have to deal with radiation as much.

Disregarding the idle chat about actually delivering the gizmo into space, you could well work on a project to see if you could make a space survivable gizmo. You would need to study areas such as the types and amounts of space radiation you would encounter, design a container that could maintain the desired enviromental conditions inside, communications that can operate with very weak signals and with significant time delays, and methods of obtaining power to run the gizmo. One reason space equipment is expensive is that it has to be extremely reliable (nothing like a cheap part making a $100M space probe fail). A reasonable starting challange would be to make a gizmo that you put out in your yard and see if it will work reliably for a month without having to go out and tinker on it. Probably harder than you would think.

[Reply #13 on:]

Not to burst your bubble, but you're not going to get a robot into orbit, let alone the moon. There is a reason why space is expensive - it's difficult to get there.

Yup, good idea, I should just give up without even attempting to identify all the problems.

I'm amazed at how, even in a forum based on exploration such as this one people still have this much negative reaction.

Now I want to do it even more just to prove you wrong.

I have a simple question regarding your reasoning about cooling.
You say that cooling the micro-controller would be a major issue, because there is "no air to take the heat away so much of it just stays in the object which heats up". So why then attaching anything to the object (heat sink) would change the situation at all? Any why, in the case of fluid cooling, the fluid would freeze, but the micro-controller would just build up heat?

The heat sink would have a larger area to radiate from. Since there's no convection to cool things radiation and conduction is the only way of removing heat (unless laser cooling becomes feasible). The heat is conducted into the heatsink which would be attached to the body of the spacecraft which would be many times the surface area of the chip.

The liquid would freeze unless I could pump as much heat into it as it loses. Since it would essentially be performing the task of the heat sink, moving the heat from the heat production to the body of the spacecraft it would be losing as much heat as the heatsink would, except it would need to remain liquid (otherwise it wouldn't have convection and heat would build up locally). The issue would be that obviously I couldn't use water as it would short everything out, I'd have to use some kind of non-conductive oil or something which would get very viscous at low temperatures and stop doing its job.

And if he has a spare 40 thousand dollars or so he can launch with cubesat, into a tumbling low earth orbit. This isn't the moon. The moon would cost hundreds of millions to reach, and anything that goes there will NOT be offering piggyback rides.

Like I said, this is the pre-pre-pre-pre-planning stage. I'm not concerned, for the moment, with how I'm going to get there. That's the pre-pre-planning stage.

It's just not achievable by private enthusiasts, certainly ones who ask about the basics here. Lofty goals are admirable, but we shouldn't sit here and investigate the possibility of sending a lander to the moon using an arduino, because it isn't possible.

That's fine, but I want to know why isn't it possible? Also, how are you categorizing "private enthusiasts"?

Ham radio people have been putting amateur satellites in space for several decades. Check this out, I am sure there is a lot info  http://www.amsat.org/

Good to know. I knew it could be done, and probably had been. I watched the Top Gear team's fantastic failure of trying to put a reliant robin into space. I knew that was rather far fetched, but had the release mechanisms worked it might have actually made it.

What it sounds like is that getting it into LEO would be relatively simple. Getting it from LEO to lunar orbit would not be. I know electromagnetic tethers have been explored as a means of getting to HEO or GEO. At what point does this become unfeasible? Would solar sails work, or would they only work for interplanetary travel?

The idea is to take something that, on the surface, seems impossible and an insane or silly proposition and figure out what it would take to make it possible. This is how exploration works. Some guy says "I'm going to sail around the world" when most people are saying "You're a fool, you'll fall off the edge!"

Our technology is 40 years more advanced than the last time humans sent things to the surface of the moon (crashing into it doesn't count). It once took months and a lot of money to get from England to New York. I can make the same trip in a few hours for much less money and still have time to shop before returning. This is because our technology has advanced. My phone probably has more processing power than all of the largest computers in the world 60 years ago, combined. At some point it will be simple for high schooler's to have a lunar rover as their science fair project.

I just about have the skills to do it now, if not the funding. If money is the only thing holding me back I consider that a minor point...

[Reply #14 on:]

Awesome attitude and project.

I too wanted to point out that it's the reliability that costs so much. If it breaks down, you've wasted all that money spent on getting it there, let alone the development costs of the product itself. Similarly it takes a LOOONG time to prove new technology, that's why aircraft are still flying around on 70's computer technology.

The Mars rovers were only designed to work for 60 days - that's how harsh the environment is. Thanks though too a really robust set of Built In Tests, and some excellent design descisions and operations procedures, they are still going (albeit on reduced functionality).

Start off like any good [engineering] project; set out a list of high level goals (travel around on the moon taking pictures), then a list of requirements 9travels 2km per day, takes pictures at 5 megapixels), then a basic concept (a microcontroller based, ?wheeled? rover with camera), then you can start doing the detailed design and picking components.