7 ms·
Part of the reason for using a swarm is rather than just one Arkyd is, counter-intuitively, the cost. “The key is redundancy and safety in numbers. We’re planni
by shabble 14y ago
Part of the reason for using a swarm is rather than just one Arkyd is, counter-intuitively, the cost. “The key is redundancy and safety in numbers. We’re planning for a certain amount of failure, and it’s a lot cheaper to work for 80% reliability than it is for 99.9% reliability.”
This is going to be the killer [NPI] feature of using automated rather than manned systems. Aiming for just-reliable-enough + spares, rather than Failure Is Not An Option is going to impact just about every single part of it, and reduce costs massively.
- Nogwater 14y agoNPI?
- davidcuddeback 14y ago> This is going to be the killer [NPI] feature of using automated rather than manned systems. Using automated systems rather than manned systems is a necessary but not sufficient condition to allow for relaxed reliability requirements in spacecraft. Another necessary condition is reduced cost. It's common for a single mission to cost hundreds of millions of dollars, which makes many spacecraft designers very risk-adverse. When I was in college, I worked at PolySat [1] where I wrote embedded software for CubeSat-class satellites. CubeSats are fairly revolutionary in the spacecraft business, because they can be launched for less than one million dollars (including development costs). The cost of the hardware was less than $10k for a single satellite and the launch costs are around $40k per kilogram (which is the maximum weight of a 1U CubeSat). Those costs are low enough that we built backup flight units in addition to engineering units. In one case, we were able to launch a backup flight unit of a satellite that was destroyed in a launch failure. (CP2 was on the crashed Dnepr-1 of July 2006 [2]. We relaunched the backup flight model as CP4.) That was only possible because the cost was so low. $50k to relaunch a satellite is unheard of. [1] http://polysat.calpoly.edu/ http://polysat.calpoly.edu/ [2] http://en.wikipedia.org/wiki/Dnepr-1 http://en.wikipedia.org/wiki/Dnepr-1
- MPSimmons 14y agoI agree with you, but once there are orbital factories (and how far are we from that with companies like this? 20 years?), the cost to "launch" becomes next to nothing.
- jimmyvanhalen 14y ago>How Billionaire Asteroid Miners Make Money -- Without Mining Asteroids. They're going to make a movie about this starring Bruce Willis. Throw in Ben Affleck for comic relief. They're going to call it "Armageddon" and it's going to be a blockbuster.
- jamesaguilar 14y agoTwenty years seems a little optimistic. We don't have ground-based automated factories yet -- not fully automated anyway. And the cost to lift a ground-based factory (or even its parts) to space on tonnage alone would be astronomical. Plus, many things are harder in a vacuum. So you're looking at some significant technological progress before what you're suggesting will be possible. Let's target rational exuberance.
- comicjk 14y agoHuman beings will accept some probability of death on manned missions - notably soldiers, but also miners and fishermen. It's politically unfeasible for NASA to plan a 5% chance of astronauts not coming home, but private companies could do it (I would take that risk to be an astronaut, especially for a good paycheck).
- nknight 14y agoIf you look up the mortality rates for things like mining, fishing, or logging in the US, you'll find that they tend to run between 0.01% and 0.05%. You're proposing a risk 100 to 500 times what the most dangerous ground-based jobs run. I have no doubt there are some people who would accept that risk, but the political problems with it don't end just because they're not government employees.
- lobotryas 14y agoSlight quibble because you said "most dangerous ground based jobs". Consider the mortality rates for soldiers in combat zones and police officers in the US. That said, I am curious why people think that space travel is safe or that space casualties are unacceptable. Without implying anything, if we seem to think it's good and honorable to die fighting for your country, then it should be just as honorable to die fighting for you country's scientific advancement.
- DanBC 14y agoIn 2006 there were about 861000 police officers in the US, and about 150 die in the line of duty each year. That's about 0.02 % I understand the sentiment, but people are not rational when it comes to risk. See, for example, the number of people who die in road traffic accidents because they're avoiding "dangerous" air travel after terrorist atrocities. EDIT: So politically it's very hard to give any suggestion that your programme of scientific exploration will have anyone dying, even though that's a very real risk. (I may have horribly botched this; I've just woken up.)
- 14y ago
- btilly 14y agoIf 20% of their satellites become space junk, and they are putting a lot up there, they are going a long way towards making the http://en.wikipedia.org/wiki/Kessler_syndrome http://en.wikipedia.org/wiki/Kessler_syndrome go from a theoretical possibility to a depressing reality. The sad part is that, since they already planned on a high failure rate, they would still be OK. It is just everyone else who would be hosed.
- shabble 14y agoIt's possible that even a 'failed' device by their mission standards is still capable of sufficient manoeuvring to either push itself into a stable salvageable orbit, or do a controlled burn-up reentry. I can think of a whole bunch of things that could go wrong which leave them unable to perform their primary objective, but still serve 'light duties' doing something else. In addition, I don't know how well we have the current debris identified and tracked, but to my entirely uneducated mind, a bunch of cheap mini-telescope sats might be quite useful in actually figuring out what we have to deal with. And, should they happen to be completely successful in their long term goals, I like to think that $20E12 in materials just waiting to be collected from a lagrange point or whatever would provide some serious impetus for solving the debris issue. :)
- DanBC 14y ago> I don't know how well we have the current debris identified and tracked NASA has an interesting website, with facts about how much stuff is up there, and images of what damage can occur. (http://orbitaldebris.jsc.nasa.gov/ http://orbitaldebris.jsc.nasa.gov/) > More than 21,000 orbital debris larger than 10 cm are known to exist. The estimated population of particles between 1 and 10 cm in diameter is approximately 500,000. The number of particles smaller than 1 cm exceeds 100 million.
- nmridul 14y agoTime for a space mining (/scavenging) company. Mine (/scavenge) the broken space ships and bring the costly metals back home. Should be less risky, good returns venture for sure..
- Karellen 14y agoThe thing is, with the amount of reliability/failure data they'll get from this, learning what fails and what doesn't and why, they'll probably get better reliability in the long term than if they'd gone for low-volume-high-cost reliability from the outset.