Planetary's approach to microsatellites is VERY daring. Instead of flying bulletproof, radiation-hardened single vehicles (like NASA or JPL), they plan to put up scads of cheap, disposable spacecraft using off-the-shelf hardware.
This is an uncommon approach, and IMO it perfectly meshes with their exclusive use of unmanned vehicles. Who cares about reliability, it's just a robot and there are many more where it came from...
As an example of the "off-the-shelf hardware" thing, they are even looking at using WiFi (and high-gain antennas) to communicate with orbiting satellites until they can get laser communications (or enough money to buy time on the Deep Space Network).
EDIT: Another example is that instead of a purpose-built real-time OS (like VxWorks, which JPL used on the Spirit and Opportunity Mars rovers), they are using Linux with a real-time patch. Maybe it's not quite as reliable, but it's much more powerful.
Source: Planetary recently gave a talk at my university. I'm sure most of this is up on their website as well.
>Planetary's approach to microsatellites is VERY daring. Instead of flying bulletproof, radiation-hardened single vehicles (like NASA or JPL), they plan to put up scads of cheap, disposable spacecraft using off-the-shelf hardware.
>Who cares about reliability, it's just a robot and there are many more where it came from...
I'd expect anyone whose orbital hardware isn't cheap and disposable might care about scads of unreliable, soon to be junk being tossed up there.
Define "up there". Space junk is only an issue because it's in the wrong orbit, regardless of how cheap their hardware is they can avoid it becoming an issue by inserting it into an appropriate orbit where it'll burn up or be directed away from the Earth. As I understand it in the long term they aren't going to be doing much in LEO anyway where space junk is an issue.
The US is, from what I can see, very concerned about space junk (as well it should be). I'm sure anything that will be hanging around is going into very Low Earth Orbit where the atmosphere will very predictably pull it in and burn it up on a reasonable and completely passive-physics-driven schedule.
True, space junk is an issue, and I don't know what Planetary is doing to mitigate that.
But, bear in mind that only the Arkyd 100 is supposed to stay in Earth orbit. The planned 200, 300, etc. all boost off in various directions (investigating and later, exploring asteroids) so their eventual fate doesn't matter as much.
> Planetary's approach to microsatellites is VERY daring.
> Who cares about reliability, it's just a robot and there are many more where it came from...
Well, the whole reason governments and corporations spend so much to ensure reliability is that the cost per kg to get to LEO is exorbitant. It doesn't make any sense for you to say that PR's major insight is moving in what has always been a non-optimal direction along the production possibility frontier unless you also include what advancement has made that direction now a good place to go.
It seems much more likely that PR's advantage, if they have one, is in miniaturization technology (to pack more in per kg, as they claim) or some sort of launch economy of scale.
This is the key imo, they are able to lower the cost to launch these into orbit because they are so small allowing them to be secondary or tertiary payloads on a rocket going up already.
>It seems much more likely that PR's advantage, if they have one, is in miniaturization technology
Part of the miniaturization could be from not including multiple redundant, hardened systems.
If you have 3 smaller satellites that are 90% reliable (for a given time frame), that vastly trumps 1 larger satellite that is 99% reliable (assuming similar capabilities and overall weight).
The trade-off between weight and reliability through redundancy is well-known to the multi-billion dollar, half-century-old space industry. This is not some new advance or insight made by PR. The only interesting thing is if PR has developed some new piece of technology which, incidentally, shifts the optimal point along the redundancy-weight curve.
They use single string commercial components but have tested them in a particle acceleration for radiation tolerance. Also the software must take into account that upsets or breakage can happen.
NASA and other space organizations and companies do much more expensive and comprehensive radiation testing, something like 100,000 dollars per integrated circuit, while MOST probably did all the components in total for that kind of sum.
And MOST is in a 800 km orbit, worse radiation than ISS.
It's space technology, all kinds of myths are spread around. If there would be more openness, diversity and launch opportunities, progress would really take off as new solutions could be simply tested.
This is an uncommon approach, and IMO it perfectly meshes with their exclusive use of unmanned vehicles. Who cares about reliability, it's just a robot and there are many more where it came from...
As an example of the "off-the-shelf hardware" thing, they are even looking at using WiFi (and high-gain antennas) to communicate with orbiting satellites until they can get laser communications (or enough money to buy time on the Deep Space Network).
EDIT: Another example is that instead of a purpose-built real-time OS (like VxWorks, which JPL used on the Spirit and Opportunity Mars rovers), they are using Linux with a real-time patch. Maybe it's not quite as reliable, but it's much more powerful.
Source: Planetary recently gave a talk at my university. I'm sure most of this is up on their website as well.