KickSat Sprites aboard CRS 3

[Kabloona]

Did I unerstand correctly?
This "satellite" consists of a bare PCB with some components & a solar panel mounted on it, and that's all?
And it should have survived space environment?
And it costed 30,000 %?

Before sending a circuit to the space... isn't a designer supposed to know something about space? Something like -100°C/+100°C range , ionizing radiation, cosmic rays and kilorads??

Why didn't anybody explained these things to the designer (and to backers) in last 4 years??

I'm astonished.

Give him a break. Of course he "knows something about space." This was a PhD project with very limited funds. Nanosats like this with short lifetimes commonly use non-radiation-hardened parts that are vulnerable to SEU. He took a calculated risk and got unlucky.

[eriblo]

Did I unerstand correctly?
This "satellite" consists of a bare PCB with some components & a solar panel mounted on it, and that's all?
And it should have survived space environment?
And it costed 30,000 %?

Before sending a circuit to the space... isn't a designer supposed to know something about space? Something like -100°C/+100°C range , ionizing radiation, cosmic rays and kilorads??

Why didn't anybody explained these things to the designer (and to backers) in last 4 years??

I'm astonished.

Are you confusing the
KickSat - A fairly standard 1U CubeSat with a 2U dispenser containing over a hundred
Sprites - Small "bare PCBs with some components and solar cells" femtosatellites?

The Sprites "cost" 300 $ each and were only supposed to spend at most a few weeks in orbit before reentering. As far as I know both KickSat and the Sprites survived the space environment just fine. The satellite experienced an unfortunate radiation event that reset the deployment timer (an issue that will be designed for in the future) which delayed deployment of the Sprites. Otherwise it appears to have functioned as designed until reentry.

[jumpjack]

The Sprites "cost" 300 $ each and were only supposed to spend at most a few weeks in orbit before reentering.

Question is still valid: how are they supposed to survive even an hour? Have they any sort of envelope, case, boxing, or anything? It's not visible on the site.

[Lar]

The Sprites "cost" 300 $ each and were only supposed to spend at most a few weeks in orbit before reentering.

Question is still valid: how are they supposed to survive even an hour? Have they any sort of envelope, case, boxing, or anything? It's not visible on the site.

I don't think they do but I would ask, why do they need any of those things to achieve their mission and hit their cost point?

[Kabloona]

The Sprites "cost" 300 $ each and were only supposed to spend at most a few weeks in orbit before reentering.

Question is still valid: how are they supposed to survive even an hour? Have they any sort of envelope, case, boxing, or anything? It's not visible on the site.

No, the Sprites were tiny unshielded PC boards with a few components.

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

The Sprites were expected to re-enter in a matter of days, so their design lifetime was short, yes. So, yeah, maybe a hundred thermal cycles or an unlucky cosmic ray kills it. But even an unshielded board can survive that environment a few days.

[Llian Rhydderch]

The Sprites "cost" 300 $ each and were only supposed to spend at most a few weeks in orbit before reentering.

Question is still valid: how are they supposed to survive even an hour? Have they any sort of envelope, case, boxing, or anything? It's not visible on the site.

No, the Sprites were tiny unshielded PC boards with a few components.

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

The Sprites were expected to re-enter in a matter of days, so their design lifetime was short, yes. So, yeah, maybe a hundred thermal cycles or an unlucky cosmic ray kills it. But even an unshielded board can survive that environment a few days.

... and moreover, would provide some degree of statistically significant data on the short-term survival of such basic and low-cost technology had the deployment mechanism on the KickSat itself not have had the unfortunate radiation event.

[jumpjack]

I don't think they do but I would ask, why do they need any of those things to achieve their mission and hit their cost point?

yes, this is another good question; the real cost of each board is no more than 50$! I guess 300$ is just a fake cost to encourage more and more people to back the project, to cover launch costs.
Not so fair...

[jumpjack]

But even an unshielded board can survive that environment a few days.

No bare circuit could ever last a few minutes under direct sunlight in space: it would reach 200°C in a matter of seconds, also due to tiny mass.

... and moreover, would provide some degree of statistically significant data on the short-term survival of such basic and low-cost technology had the deployment mechanism on the KickSat itself not have had the unfortunate radiation event.

No doubt about valuable data retrievable from such a mission... but the most important would be: which is the minimum volume allowing providing thermal protection to a circuit in space? How long does it last with only passive cooling/heating?

[ChrisWilson68]

I don't think they do but I would ask, why do they need any of those things to achieve their mission and hit their cost point?

yes, this is another good question; the real cost of each board is no more than 50$! I guess 300$ is just a fake cost to encourage more and more people to back the project, to cover launch costs.
Not so fair...

That's really crazy.  Of course the $300 includes launch costs.  How is that "fake" or "not fair"?  They're getting launched into space, why wouldn't they pay their part of the launch costs?

[ChrisWilson68]

the demand might come from the consumer market.  While fault-tolerant high-availability systems are generally available only in the higher-end "enterprise class" of computing systems (servers, data storage controllers, etc.), at many times the price, the consumer market is large enough to drive change itself.  We could see a future, and possibly a near future, where consumer demand for better quality PCs/tablet/smartphones (fewer resets, need to reboot in the middle of important use of the device, etc.) may incent chip makers to package hardware in more-capable and more highly integrated chips/memory/storage specifically aimed at a consumer fault-tolerant market.

The vast majority of lock-ups, reboots, etc. on consumer devices today are due to software bugs, not cosmic rays or anything else.  There's already a lot of fault detection for hardware events even in embedded chips in consumer devices.

[jumpjack]

That's really crazy.  Of course the $300 includes launch costs.  How is that "fake" or "not fair"?  They're getting launched into space, why wouldn't they pay their part of the launch costs?

Then I would have written in the project page "Board cost is just xx$, but we need yy$ per each sprite to cover launch costs": this is supposed to be an educational project (I guess). I would also publish full design... unless they're trying to make money from this project... and I can't imagine how (and kickstarter itself is not supposed to be a method to earn money...).

[Chris Bergin]

Alright, let it go. We don't need 15 pages of this (which is what I fear may happen).

[jumpjack]

Why not? Version 2.0 of the project is already planned, I think some feedback and new ideas would be useful... to original designer or to next Space Pioneer! :-)

[Lar]

Why not? Version 2.0 of the project is already planned, I think some feedback and new ideas would be useful... to original designer or to next Space Pioneer! :-)

Because you were told not to. By the site owner. It's not clear to me how it could be made any clearer.

If you have an issue with a moderator action, use the PM button or the report to moderator button. DO NOT DEBATE onforum.

[Bob Shaw]

I'm certainly looking forward to KickSat II; as a participant, I have no issues with the performance of KickSat 1. It reached orbit (a minor miracle) and communicated with the ground. It had a failure, which was diagnosed but couldn't be corrected. Lessons were learned, and I hope they will be applied. At that point we will see the proof of concept with regard to the sprites themselves (hopefully the launch won't be subject to quite so many orbital limitations next time so that the actual lifetime of sprites can be identified).

All in all, I can't wait.

Now, about those thin-film, printed femtosats being sent to the Moon...

[mlindner]

Did I unerstand correctly?
This "satellite" consists of a bare PCB with some components & a solar panel mounted on it, and that's all?
And it should have survived space environment?
And it costed 30,000 %?

Before sending a circuit to the space... isn't a designer supposed to know something about space? Something like -100°C/+100°C range , ionizing radiation, cosmic rays and kilorads??

Why didn't anybody explained these things to the designer (and to backers) in last 4 years??

I'm astonished.

Most cubesats are bare PCBs possibly with some clear coating to stop screws and nuts vibrating loose and to improve heat conduction. I've not read about any cubesat that used rad-hardend parts as primary components (not saying there aren't any, I just haven't heard of any). You just eat the radiation and hope for the best. Cubesats don't use any heaters or cooling either. The single PCB sprites would have worked perfectly fine.

Just speaking as someone who actually built cubesats, observed live telemetry from code I wrote delivering the temperatures of said cubesat to our ground station, I don't think you know very much about the space environment at all. Just FYI.

I don't think they do but I would ask, why do they need any of those things to achieve their mission and hit their cost point?

yes, this is another good question; the real cost of each board is no more than 50$! I guess 300$ is just a fake cost to encourage more and more people to back the project, to cover launch costs.
Not so fair...

The parts may be $50, but labor isn't free. $300 is a pretty reasonable price for time and effort put into the sprites.

But even an unshielded board can survive that environment a few days.

No bare circuit could ever last a few minutes under direct sunlight in space: it would reach 200°C in a matter of seconds, also due to tiny mass.

Completely absurd. Sheets of copper (metal layers in a PCB) emit radiation quite well. The temperature would have done no such thing.

... and moreover, would provide some degree of statistically significant data on the short-term survival of such basic and low-cost technology had the deployment mechanism on the KickSat itself not have had the unfortunate radiation event.

No doubt about valuable data retrievable from such a mission... but the most important would be: which is the minimum volume allowing providing thermal protection to a circuit in space? How long does it last with only passive cooling/heating?

Probably years given other examples of cubesats built exactly the same way. There's been talk of making satellites that are literally strings of PCB boards floating around together chained together by their connector cables with no structure what-so-ever.

[mlindner]

I'd heard of FRAM memory, but didn't know it was used in microprocessors themselves - it's interesting to also note the longevity of PowerPC CPUs in space applications, long after Apple gave up on them!

Old post reply, but thought I'd mention PowerPC is used extensively many places. You probably have PowerPC processors in your car. They were/are the go-to main processor for vehicles AFAIK. I don't know much about the aero side but I would not be surprised to see them used extensively there as well.

[cosmicvoid]

... snip ... There's been talk of making satellites that are literally strings of PCB boards floating around together chained together by their connector cables with no structure what-so-ever.

That would be OK for on-orbit, but not so much for the G forces of launch and deployment, I think.

[mlindner]

... snip ... There's been talk of making satellites that are literally strings of PCB boards floating around together chained together by their connector cables with no structure what-so-ever.

That would be OK for on-orbit, but not so much for the G forces of launch and deployment, I think.

Thus why there's only "been talk" so far.

[Bob Shaw]

New post from Zac Manchester to the KickSat supporters:

"Remember the prototype Sprites I showed off during my original Kickstarter video?

Those were from the first batch of Sprites we made back in 2010. As some of you may know, we were lucky enough to be able to send three of those early prototypes to the ISS on STS-134 (the second-to-last Space Shuttle mission). The Sprites were installed on the outside of the space station as part of the MISSE-8 experiment, where they stayed for three years. Here are a couple of pictures from the spacewalk when MISSE-8 was installed (notice the three Sprites in the second photo).

In a very cool turn of events, MISSE-8 was returned to Earth on May 18 inside the same Dragon capsule that KickSat rode into space with as part of the CRS-3 mission. A few days ago our Sprites finally finished their long journey, making it all the way back to the lab at Cornell where they were made. As you can see, they've clearly been through a lot.

We were very curious to see how well the Sprites' off-the-shelf electronics held up to three years of space radiation. After a quick trip to the hardware store to track down an incandescent lamp (thanks to Ithaca's rainy weather, there wasn't enough real sunlight to power the Sprite's solar cells), we were to detect strong radio transmissions from two of the three Sprites. We still have a lot more testing to do, but this is a very promising first indication that the components we're using on the Sprites can survive for long periods of time in the harsh space environment. I'll keep you all posted as we learn more.

- Zac

Fascinating - and a serious on-orbit test of the components (exactly what many of the (negative) commentators on here were demanding).

Now, about KickSat 2...