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Comment Re:Here's the skinny if you don't like link bait (Score 1) 76

Thanks for checking out the page, I appreciate the comment! The nature of the project and the kind of coverage we've been getting is making people (understandably) wary, so I relish the chance to tell people more and show what we've actually doing.

To get your own sensors on there, we're running a competition right now sponsored by Discover Magazine where anyone can suggest ideas for sensors to add to the satellite and what they would do with it if we flew it - if they pick your idea we'd put it up there for free, and Discover buys the person who submitted the idea with a development kit/functional copy of the payload (our $1500 pledge level). I don't want to spam the thread, but the full contest rules are here and can give you more details:

Re: pointing - The sensors and camera can be pointed in any direction, the whole satellite reorients itself using magnetotorquers.

Re: schools - We're trying to chase down a number of schools to see if they want to run low-cost experiments, and I'd really like to see if any university wants to add a hosted payload - depending on what they want to do I think we could probably give them help for pretty cheap.

Re: Radhard - The satellite body gives a little radiation shielding, enough for the Arduinos to survive long enough for the mission (we're aiming for 18 months). The single-event problems we're mitigating by running code on a number of redundant processors simultaneously to filter out random errors, and the mission-critical systems and main computer are all running using rad-hardened components with space heritage.

Cheers, Joel

Comment Re:But.. (Score 1) 76

Hmm, we might need to let a few other people run their experiments first...

A couple people have mentioned thrusters on the thread - sadly, we don't have any propulsion on the satellite, so although you can control the satellite's orientation, kamikaze missions might be a little hard.

Cheers, Joel

Comment Re:Here's the skinny if you don't like link bait (Score 1) 76

- For the pictures, you're absolutely right, the image quality (and pointing accuracy) is what is going to determine if it's worth the $10 an image. We're booking a spot on a high-altitude balloon (about 100,000 feet) in September to test out the payload and cameras, so that people can see the quality and send us feedback. Unfortunately we won't have the results until after the Kickstarter, which sucks because we can't show people the images BEFORE they pledge, but needed to get the funding for the space-heritage hardware early so we'd stand have a better negotiating position for launches, which needs to happen way in advance of the target launch date (first half of 2013).

- In space, no one can hear you trolololololo... For the messages, it'll be broadcast at around 437 MHz, so you can hear it using a HAM radio. We realize not everyone has a HAM radio just chilling on their coffee table, so we're also going to live-stream the audio as heard by our ground station(s) on our website.

- The here's the lists of the sensor packages, I won't put the link to the Kickstarter page (not a good idea to put a lot of links on an anti-linkbait thread!) but I still want to answer the question: (for the $500 package) and here: (for the $800 package).

- Once you download your data from the satellite, it's all yours, to distribute however you like.

TL;DR = If you want to know more or poke holes in the idea, ask away! I'll this thread daily to answer questions.

Cheers, Joel

Comment Re:"Hopeful" language (Score 1) 76

Not a problem re: the GPS, people are definitely in the right to ask questions about the design and try and poke holes in it!

Re: too good to be true, that's a problem we're running into a lot (especially on Slashdot!), people being incredulous because it sounds too easy, or thinking it's a scam and because we're doing so much of our outreach in the internet. l actually love it when people who know what they're talking about ask any questions about the design, it gives us to have a real discussion and try and show everyone that this ISN'T just a pipe dream.

Cheers, Joel

Comment Re:Why arduino? (Score 2) 76

The point of using Arduinos wasn't to go cheap on components, but to make the actual satellite itself more accessible and easier to write code for. In fact, we're doing the opposite of going cheap in terms of hardware: the guts of the components for the satellite itself (not the payload) are all pretty costly because they're all space-rated (and most of them are space-proven).

The expensive hardware is the whole reason we need the Kickstarter campagin!

Joel (ArduSat developer)

Comment Re:"Hopeful" language (Score 1) 76

Yup, you got it - the camera itself isn't run on Arduino, but it's still controllable from the payload Arduinos.

Ack, you're right, we forgot to put the cameras in the package descriptions - thanks for the heads-up!

The idea main idea with putting the code itself in space is to let people write code that could actually use the sensor/bus data for real-time control, and actually play around with the satellite control system. It's more fun that way, wouldn't you agree? We thought actually using a satellite would be more appealing/rewarding for students/educational groups too.

Re: the GPS and other sensors, they're all either space-rated (and actually space-proven, in the case of the GPS), and the one's that aren't are going to need some limited climate control.

Joel (ArduSat developer)

Comment Re:"Hopeful" language (Score 2) 76

In terms of the image memory issue, the image processing won't be done on an Arduino, but by the flight control computer (the design baseline uses a GOMSpace NanoMind 712C), which uses a 2GB SD card for storage until we can downlink it. Our downlink rate is around 4800kbps, so we've estimated a full-res image download time of under a two minutes. We won't be taking live video, because you're right, you can't get the data down fast enough; the cameras will take single still frames.

The GPS we're using isn't a commercial receiver, it's a space-rated version that's flown successfully on previous missions.

The launch will be done on a normal rocket using the standard P-POD deployment, which is priced as low as $0 for educational missions, as high as $60k for private launches, and anywhere in between with partner arrangements.

The advantage of running the code on boards is you can also design apps that need closed-loop control of the satellite, which isn't possible if if you just downlink the data and use it on the ground.

The altitude we'll fly at isn't a perfect vacuum, and there's going to be some pretty interesting things going on with the ionosphere due to the solar maximum next year that we want to be able to have a look at. And the temperature sensors are going to be inside the casing, where there's limited thermal control to give partial isolation from the extremes of open space.

tl;dr I'd be happy to answer more questions about our design, and I'll add yours to our FAQ section on the Kickstarter.

Cheers, Joel (ArduSat developer)

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