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KSP Community CubeSat


K^2

Ultimate Mission?  

104 members have voted

  1. 1. Ultimate Mission?

    • LEO Only - Keep it safe
      55
    • Sun-Earth L1
      5
    • Sun-Earth L2
      1
    • Venus Capture
      14
    • Mars Capture
      23
    • Phobos Mission
      99
    • Jupiter Moons Mission
      14
    • Saturn Moons Mission
      14
    • Interstellar Space
      53


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Would't it basically be Curiosity-style in-atmosphere trajectory control (without the landing)? Tricky, but it has been done.

I suspect that getting the mass of thermal protection/aeroshell low enough is more difficult.

Pretty much. EDIT: I had been going off Wikipedia saying aerocapture had never been done; I was unaware rovers have done direct entry from hyperbolic orbit.

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wow, 25 pages in 2 days.. This is gathering a lot of attention.

The idea is good, and it can be done.

I read only the first 15 pages, so sorry if I repeat something.

The most important is the chosen mission and (maybe) second mission.

If its an interesting mission with real practical value, then raise funds would be a lot easier.

For those who talk about solar system missions like phobos, venus, moon, etc.

I think that it would be only feasible in the next 5 years in case the launch cost were reduced to 1/7 at least.

In that case, my vote it would be for a Venus mission with aero capture to place a spacecraft ballon to take pictures at 60 km of altitude. (which no even soviets or nasa did it)

The same ballon that we use to float in Venus atmosphere, would serve also to provide a safe aerocapture reducing the overall density of the spacecraft.

This would be easier than try to land in phobos.

By easy I mean (90% of chance that something would go wrong), also we need use the already satellites launched in the solar system to transmit the data, for example the venus express satellite from ESA is reaching their final days.

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But a more realistic scenario it would be a low earth orbit mission.

What it would be the science value in that?

We can test an E-sail (already mention in the page 14), that it will consist in a long conductive tether with a little load in the extreme.

With this tether we can try to collect energy without using much PV and as deorbiting force. Using this configuration we can also use the gravity gradient to point always to the earth without reaction wheels.

For a secondary mission if we achieve go back to earth, we can test an reentry aerobrake system for cubesats.

PD: I hear that people use cellphones in cubesats as Camera, unit procesor, accelerometer, etc. Also the software is easier to develop.

Edited by AngelLestat
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I see no reason why we can't raise the required funds through kickstarter or gofundme. A guy has raised $37,000 to make potato salad for pete's sake.

http://eater.com/archives/2014/07/07/man-raises-thousands-of-dollars-to-make-potato-salad-1.php

And a lot more people failed to meet their goals. The Kickstarter success rate is 43% for *all* projects; a site I found estimated 7% success for projects with a goal over $100,000. That one person's project went viral, explaining the huge amount of money given. It's not representative of anything.

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And a lot more people failed to meet their goals. The Kickstarter success rate is 43% for *all* projects; a site I found estimated 7% success for projects with a goal over $100,000. That one person's project went viral, explaining the huge amount of money given. It's not representative of anything.

True, but IMO, if any project has the potential to go viral, I think it's this one.

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I have a feeling that a lot of people who might be helpful for this project will be turned off by a huge influx of nonsensical posts that lead nowhere.

Landing a CubeSat on a Martian satellite? Really?

I can't decide what's more futile - thumping that ludicrous idea down or the idea itself.

I acknowledge and appreciate the interest, however all but several people here, including myself, know at least a bit how difficult some of these things are, and others just spam the thread with "let's get a sample of cheese from the Moon" posts.

Be reasonable, folks.

Let's get visual.

The probability of success for deploying a microsatellite in LEO by a KSP forum group is the size of a mouse.

The probability of anyone of us putting a Kerbal figurine in stratosphere by a balloon is the size of an elephant.

The probability of substantial economic growth of France in the next 5 years is the size of an Eiffel Tower.

The probability of putting a CubeSat in GEO is the size of a flea.

The probability of putting a CubeSat in GEO and actually communicating with it is the size of a red blood cell.

The probability of doing anything that involves solar orbit and other planets is somewhere between the size of a quark and the postulated superstrings. Which is a very small number.

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I slept, and then the thread size balloons... with heated discussion

Well Phobos mission will have problems in antenna pointing, unless if you put a star tracker there. And then there still be transmit power issue

So, I suggest a new mission:

2U to LEO, and try to do laser communication with it. Everyone that have good enough telescope could aim to that cubesat like we did to ISS, and attach a camera to there, decoding the flashes of laser light.

Feasibility? Any LEO mission that this forum has concocted can have a several watt red laser diode without massive mass penalty, so consider this as the secondary objective

Usefulness? If this succeed, we can have a faster downlink than radio, and energy saving too

EDIT: I think the laser isn't powerful enough to be seen at Earth, and the telescope needs tracking capabilities too, which is hard

Edited by Aghanim
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2U to LEO, and try to do laser communication with it. Everyone that have good enough telescope could aim to that cubesat like we did to ISS, and attach a camera to there, decoding the flashes of laser light.

Feasibility? Any LEO mission that this forum has concocted can have a several watt red laser diode without massive mass penalty, so consider this as the secondary objective

If it's a laser, you can't have everyone with a good enough telescope viewing it. Laser beams are narrow; that's the whole point of lasers. While it wouldn't be the size of a laser pointer beam (it would be substantially bigger than that), it would still have to track a ground station. There are ways to make this work, but those also work for radio signals. Lasers would not be faster; why would they be? Radio waves are also light.

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I just realized my mistake now, for laser communication to be successful the cubesat and the receiver needs to cooperate, which means you are right. But is laser communication faster than radio signal? LLCD says yes, but we could not hope for that amazing performance

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Lasers are faster in terms of data transfer rate, because a visible light or even infrared laser has a shorter wavelength than radio waves.

However, a single laser only has two states; radio systems easily have many more than two symbols.

EDIT: Apparently LLCD had 2 states as well. Disregard this post.

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Radio waves are not light, are just another part of the spectrum. Light speed has nothing to do with bandwidth.

Why Li-fy is many times faster than wi-fy?

My problem with this approach is that nasa already did this from the ISS, they transmited a large video using lasers in few seconds.

Instead, my suggestion was never try it. And you can measure many things with just one cheap thing, there is no need of reaction whells either, and we dont contribute with space debris because it also work as deorbiting technique.

GO GO space tether!! XD

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The probability of putting a CubeSat in GEO is the size of a flea.

The probability of putting a CubeSat in GEO and actually communicating with it is the size of a red blood cell.

The probability of doing anything that involves solar orbit and other planets is somewhere between the size of a quark and the postulated superstrings. Which is a very small number.

If you think putting something in GEO is easier than putting it in Solar orbit, you understand nothing about orbital mechanics.

We can test an E-sail (already mention in the page 14), that it will consist in a long conductive tether with a little load in the extreme.

With this tether we can try to collect energy without using much PV and as deorbiting force. Using this configuration we can also use the gravity gradient to point always to the earth without reaction wheels.

We'll be very limited in terms of length of tether by the mass and size of the sat. I'll run the numbers. It'd be a great thing to try if we can get any serious amount of thrust out of it.

There are a few other interesting LEO propulsion ideas that could be tried out.

For Phobos mission, how would you protect and control the satellite during aerocapture?

The force isn't actually that high. For a 3U, we'd be talking about something like 30-50N on average during maneuver. The heat is considerable, but nothing like a reentry. Mostly because you have thousands rather than hundreds of km you can use for braking. With some reasonable shielding, it's survivable.

Control is a much bigger issue. Atmosphere isn't terribly predictable, and this is an extremely delicate maneuver. Still, you have about 30% of escape velocity for your error bars in general for a capture. This would require extendable heat shields that can be used in thinner atmosphere to increase drag, retracted in during passage through thicker atmo, where ablative shield in the front would be utilized, and extended again on exit. On exit, the shields/brakes can be extended more or less depending on how much velocity has been lost. It wouldn't allow for too much correction, but it will help.

And I'll be honest here, a big part of it would involve getting lucky. That said, this mission ending as a streak of light in Martian sky, or with the cubesat bouncing off back into interplanetary space and getting lost there for good, would not be a shameful result. In fact, even if it ends almost two years earlier, as a crater on the Moon, I'd call it result exceeding expectations.

But that only makes such a mission so much better fitted for a KSP community. If it succeeds, it would be against impossible odds. If it fails, it would fails spectacularly having done more than anyone expected of it.

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If you think putting something in GEO is easier than putting it in Solar orbit, you understand nothing about orbital mechanics.

If you think putting something in GEO is harder than putting it into solar orbit, you know nothing of the launch market. Secondary launch opportunities to full GSO, while not exactly cheap ($490k for a 1U cubesat) are available; flights to solar orbit simply are not.

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If you think putting something in GEO is harder than putting it into solar orbit, you know nothing of the launch market. Secondary launch opportunities to full GSO, while not exactly cheap ($490k for a 1U cubesat) are available; flights to solar orbit simply are not.

Isn't the plan for solar orbit involves getting a ride to GTO and then use the onboard BRFIT-3 ion thruster, using the moon and the earth as gravity slingshot target? Of course, communication and control are very very hard

Edited by Aghanim
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I think getting a sat into LEO, while difficult to raise funds for, is doable. We just have to get creative as far as objectives once it's in orbit. I personally think we should try to come up with a cheap, compact way to to make reentry survivable. Something that can be scaled up. A miniature ballute, just as an example. Something that's never been tried before. More likely to peak nasa's interest and get them to give us a free ride.

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If you think putting something in GEO is harder than putting it into solar orbit, you know nothing of the launch market. Secondary launch opportunities to full GSO, while not exactly cheap ($490k for a 1U cubesat) are available; flights to solar orbit simply are not.

Do you see the LLO launches? Where do you think you cubesat will end up if you release it on LTO? That's as far as basic "I have money I want to waste," options. A GTO to LTO boost can be done with a cube for significantly less than paying for a GSO/LLO ride.

So again, when "easier" includes funding the whole thing, yeah, escaping Earth is way easier than getting to GSO. But if you happen to have $500k you're not using, sure, lets put a sat in GSO.

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K^2, what's the cheapest ride you've found? And do any of you have any ideas on what the CubeSat could do ounce in LEO?

EDIT: Kevon87, that's one of CAT's early things, they've been already funded in there KickStarter campaign.

Edited by Nicholander
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