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Getting the Latest Rover To Mars
derGoldstein writes "New Scientist has a great video up detailing every step of how the latest Mars rover will reach its target and get deployed. It's drastically different than the bouncing air-bag delivery system previously used (YouTube video)."
Won't all that extra propellant for the various deceleration stages add up to a lot more than the bouncing airbag thingie in the end?
A small rover or lander can only carry a small amount of instruments. If you want to do serious science, you need a reasonable number of those.
I see that it has a laser. I hope that laser is beefy enough to let it make like a land shark and defend itself if the Martians stumbleupon it.
This rover is FAR larger the current ones, those tires? Not cute cart wheels, they are roughly the same size as a car tire. The entire vehicle is easily the size of a large SUV although far more open. (Hey nasa, if you want to make things understandable how about instead of adding sounds in space, maybe project a human next to thing so we get a sense of scale)
A bouncing ball for this vehicle wouldn't need to be far to large. It is the old story of how spider won't even notice a 4 meter fall, a human would shatter bones and an elephant would go splat.
There are a lot of risks with this method, so many parts that can fail, but if you want something big to land safely...
Not that this is new. There are airdrop uses on this planet that involve just wrapping what you want to drop in something bouncy and throwing it out of an aircraft, works for small supplies in remote areas where a parachute might drift to far and the russians have used rocket decelerated chute systems for dropping tanks out of aircraft. Because finding enough bubble wrap for a tank is a hard.
Did I complain yet about the sound in space? Yes? Well, it is a pretty big fucking issue. Everything you need to know about the US can be summarized as a NASA science video having sound in space... why not go the whole way and include cute green aliens on mars to show the life you might have found if Mars wasn't the hell hole it is?
MMO Quests are like orgasms:
You may solo them, I prefer them in a group.
Yeah, a squad of mini-rovers coordinated with a mesh network. Maybe we could get people to root for that team instead of the useless ones in the NFL?
It's not the size, it's how you use it. ;-)
XML is like violence. If it doesn't solve your problem, you're not using enough of it. --AC
A small rover or lander can only carry a small amount of instruments. If you want to do serious science, you need a reasonable number of those.
But a single big rover with lots of instruments is useless if it's lost due to a hugely complex landing system failure, or the instruments can't be used due to a failed arm that has to rotate in multiple ways to deploy and return on each use.
From the video the entire system seems way too complex to me. I hope it's been well tested.
I never understood what is so exciting about Mars. It's fairly far away. Start close. We should have a small colony on the Moon by now. We should be there learning how to do it right now. Once we get it figured out close to home, let's actually go to Mars instead of just sending rover after rover.
How is this powered? Not the landing stages, the rover itself? The video doesn't show any solar cells on the rover. Are they omitted from the simulation for simplicity, or is it using some sort of radiosotope battery. The video mentioned it had a planned life of two years. If that's the case, and given the size of the thing, then it almost has to be. That makes perfect sense of course, it's the ideal use of the technology. But don't they always run into political obstacles when they launch anything with "nuclear" in the name?
OTOH, the whole mission is complex. Launching a rocket and guiding it to Mars has many potential points of failure, yet we've done it almost routinely. This new system allows a much larger payload to be landed. So it's progress.
Faster! Faster! Faster would be better!
Almost as complex as Apollo 11 supposedly was. Maybe someday we'll make it to the moon.
I spent half the time thinking how freaking cool and the other half thinking isnt that MANY points of failure?
I thought the beauty of the cushion landing was so few moving parts.
that hover entry vehicle lowering the rover to the ground is straight out of a video game!
http://www.awfullybigmoustache.com
That's terrible probability, like saying if I flip a coin twice I'm guaranteed to get a heads and a tails.
Unless Calculator has failed me, a 1 million part machine (with each part having a 1 in a million fail rate) has around a 63.2% chance of failing.
I am in absolute awe after watching the video about the new rover. As people bicker over whether NASA's miniscule budget is worth it, because "space isn't important", it's nice that NASA can still bring out that child-like wonder in me. How can you not be amazed that we can send a robot like this to another planet, land it safely with precision, and study the composition of the planet from millions of miles away? Isn't that awe worth a few billion dollars a year, even if "it doesn't benefit me"?
(Also, it has a laser tricorder. I mean, come on.)
The landing procedure look entirely too complex to me. It is one thing to let something crash in a controlled way, but quite another to land it in the way they desscribe. There is a host of things that could go wrong, like failing thrusters, frozen fuel lines, malfunctioning controllers, etc etc... And all that after months in space, having survived a launch and re-entry and then completely automated, with only seconds to react if something fails... I will be really,really impressed if they pull this off...
"Single point of failure" is an engineering term. A system can have any number of them.
Science is all about firing a drunk pig out of a cannon just to see what happens.
With pessimism like that, how to you do walk outside? You might fall in a manhole or get hit by a bus. Did it not occur to you that just maybe, the landing method used was deemed the best chance for success? Well then again, you're no rocket scientist are you?
What's the deal with all the "it's too complex, it'll crash" posts here?
What's the deal with nerds these days? You never accomplish what you don't try. Maybe it will crash, but maybe it won't. Better than not trying at all. And this is the sort of thing that should bring wonder and excitement to the people this site's masthead references.
It could, but that would mean landing in the same area. Mars is quite large, and it would be a shame to send a probe to the same location unless that location happens to be of extremely notable interest (such as either a potential human landing site, or something truly unique in almost science fiction proportions).
I would love to see the landing parts.
Ant(Dude) @ Quality Foraged Links (AQFL.net) & The Ant Farm (antfarm.ma.cx / antfarm.home.dhs.org).
I thought there was no sound in the vacuum of space.
But then maybe all that manmade global warming New Scientist likes to report is causing air molecules in our atmosphere to heat up and expand into the other reaches of space, causing all that whooshing noise as the mars lander speeds by the camera.
Or maybe they consulted with George Lucas before making the video...
Mars has a very thin atmosphere. It's nearly a vacuum. To generate enough lift to be worth anything, the wings for any spaceplane would have to be enormous. Atmospheric braking can work at high speeds, but once it slows down, there isn't enough drag for a parachute to slow it down to a survivable speed. If a parachute won't work, wings won't either unless they can make some sort of incredible high speed horizontal landing on very flat ground.
With the technology currently available, they seem to have made the best choices they can. Dumping parts all over the place may not appeal to you, but it's the best way to have, for example, a heat shield for atmospheric braking that you don't have to spend fuel on lowering gently to the ground afterwards. The lowering mechanism, where the rover is lowered from the hovering section is the oddest seeming part of the whole thing. I'm not sure if it's meant to lower the rover gently because the thrusters wouldn't be able to make a gentle landing, or if it's simply meant to keep the thruster section clear of the rover. If it's the former, then I suppose it makes sense. If it's the latter, then I think it would be a better idea to have the rover land with the thruster section attached, then have it detach and fly away. Then again, maybe they're worried about high speed grains of dust and rock kicked up by the thrusters. In any case, I'm not sure that anyone here criticizing the design actually has a better idea. I mean, you could imagine some sort of Voltron style rover that assembles itself from multiple independent pieces that land via airbag, for example, but it wouldn't exactly be less complicated.
And I bet the project will be scrapped due to budget cuts long before it's ever launched.
Seven puppies were harmed during the making of this post.
The Apollo astronauts commented that the mission's lander kicked up a tremendous amount of dust from the lunar surface; so much so that the blast radius was visible from the command module in orbit.
Judging from the video, there seems to be a significant risk of:
- bits of Curiosity getting fried by the descent engines
- the lander covering Curiosity with a massive amount of dust
Now, given that there are massive duststorms on Mars anyway, the team has hopefully prepared the rover to deal with being absolutely covered with martian dust, but it seems a shame to me to have to start the mission off that way as a result of the landing technique.
Perhaps they could test it in the worst part of the sub-Saharan Harmattan season?
Isn't there a write up somewhere? Wouldn't it be better to link to a write up? I don't want to spend 4m19s watching some dumb video with sound in space and fancy graphics. Spoken narrative is too slow. A write up and a diagram or 2 is enough to convey principles, which is what interests me.
What's the deal with nerds these days?
Not nerds, nerds on slashdot. That's a huge difference. Slashdot obviously has strong points, that's why I'm here. But one of the weak points is an aging user base. And old nerds face the same thing as old non-nerds. Most people just get scared of risks the older they get.
Everything will be taken away from you.
'if this single part of this entire system breaks, the whole thing is fubar. Also this part here, if IT breaks, the whole thing explodes. Or this part over here, if it falls off to soon? the whole thing crashes to the ground like a Volkswagen dropped off of a bridge.' single point of failure.
I've decided to Diversify my Holdings. I've divided my cash between my left and right pockets, instead of all in one.
I'm wondering what exactly you consider "aging", but anyway: How about "with age comes experience"? Nerds tend to work in technical fields, and experience in pretty much any technical field will teach you that the more complex a system is, the more likely it is to fail. Now, obviously you've got an entire battalion of nerds working at NASA, many of whom are "aging", so I'm assuming that they're relying on their age/experience to make the right decisions.
I also don't see how "an aging user base" is a weakness, which we don't even know to be the case, unless you've got access to demographic information that I don't. It's entirely possible that more "aging" users have stopped visiting the site, compared to the new ones that have joined.
Entomologically speaking, the spider is not a bug, it's a feature.
No need for a calculator. This type of problem (1 in n chance of an event occurring, what are the odds of it occurring in m trials, when n=m?) converges to 1 - 1/e. The total number of failures adds up to 100% (it has to be to maintain the original odds), but some of those outcomes are multiple failures (i.e. 2+ parts failing on your million part machine). If you have 100 letters which you randomly put into 100 mailboxes, some of those mailboxes will get 2+ letters, meaning obviously that some mailboxes will not get any letters. As it turns out, it's 1/e mailboxes which get no letters, and 1 - 1/e mailboxes which get at least 1 letter.
I bet it will crash. Too complex, too many points of failure.
That's why you should have budget for 2nd and 3rd try from the start. Getting as complex a thing as this right from the start is hard, so hard it might be cheaper to not try quite so hard (law of dimnishing returns and all that), but instead prepare for crash and new mission which will not crash, at least not for the same reason. That's the single most important reason to do robotic and not manned missions: crash can be an option, if having it as an option is overall cheaper.
Don't be a moron.
It's not that complex. NASA has launched much more complex systems.
Also, this one has the potential to last even longer, since it uses a RTG that'll still produce 80% power after 14 years.
I counted 8 systems where any problem at all would kill the mission:
Heatshield that has to protect, then deploy (or fall off in non-techno speak)
... and pay out slowly enough
... and detach when the lander is down safely
Guidance rockets that have to work just right
A parachute that mustn't rip or tangle
A hovering system that must balance,irrespective of any storms it may encounter
A winch that must not jam (after 40+ weeks in cold and vacuum)
and finally the hovering platform that must not run out of fuel and drop onto the lander, or think it's detached and fly off with the lander in tow (If they got that on video, I'd laugh for a week)
In short there are far too many ways it can fail, and far too many things that have to work perfectly. I think there's a bad case of hubris from having 2 landers out of 2 that not only survived the trip, but exceeded expectations. Sadly, I think this thing will even up the score.
politicians are like babies' nappies: they should both be changed regularly and for the same reasons
What's the deal with all the "it's too complex, it'll crash" posts here?
Precedent. Remember the Mars Polar Lander? Yeah, nobody else does either, because its only lasting accomplishment was a spectacular thud into the Martian surface. Why? Because of a malfunction in its landing procedure. Beagle 2 was also probably rendered inoperable by its landing procedure as well.
And don't forget that Mars Climate Orbiter was destroyed because the engineers forgot to properly convert metric to imperial. NASA is not an organization that inspires confidence these days. "Trying" shouldn't be good enough for the sort of money and talent involved. Failure should be an outside chance, not 10-20+% as it has been the last couple decades.
I support the Slashcott and will not be reading or commenting from 2/10/14 to 2/17/14. Beta is steaming pile of dog shit
As Stanislaw Lem either didn't understand statistics or was simplifying for those who don't ;-)
For an equal chance of failure = (n-1)/n, you need x=ln(1/2)/ln((n-1)/n) parts to have a greater chance of failure.
For n=10e6, that's about 693 thousand components. Quite a lot less than a million!
Correct me if I'm wrong, I won't mind.
You're only jealous cos the little penguins are talking to me.
In short, they did it because an RTG is a much more abundant and long-lived power source for this size craft. It is similar to the arguments made in favor of nuclear power over photovoltaics on Slashdot. Some more information can be found here and here.
The National Academy of Engineering had an article a long while ago about the Challenges of Landing on Mars, detailing the various merits of the systems used for Viking, Pathfinder/Spirit/Opportunity, and the upcoming Curiosity. It's a little dry, but it explains with good reasoning why the chosen landing solution is appropriate for Curiosity.
Someone needs to go watch Meet the Robinsons again.
When a Mars mission narration refers to "miles" and "feet" it makes me shudder.
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Just great. We go visit a planet that isn't ours, and the first thing we do is pollute the atmosphere with propellant, throw trash around ( the rocket lander will land 'somewhere out of the way') and with a bit of luck contaminate the area with radiation if this thing fails to land properly.
We come in pieces...
To Terminate, or not to Terminate, that's the question - SCSIROB
Ok. You got me. Whose planet is it then?
I wish that they would put this on the edge of the crater, rather than in it. If Mars has water, where would it be? Not high. It would be in the ice and at the bottom of craters. At the least, I would rather that we put it there around winter.
I prefer the "u" in honour as it seems to be missing these days.
Yeah, this is going to be a challenge to make work. I kept thinking about all the steps that have to work first time, on time, like all the explosive bolts, the radar working, the wheels deploying, descent rockets firing at just the right altitude, finding a nice smooth spot to hover over with 30 seconds (or whatever) of fuel, etc. etc.
In theory, I'm sure all of these can be solved. If they all work, I'll be impressed as hell. Forget finding life, just solving an engineering challenge like this is inspiring enough to me.
Oh you simply must watch the video. It really is something out of a Bruce Willis movie. Nothing even close to simple. I can't imagine it'll make it through to the final plan. And if it does, I can't imagine it actually working. And if it does, I hope someone goes and films it happening -- that might be the easier part. Seriously, video games aren't this cool.
Look, we got one Mars landing method that got 3 successes for 3 tries, 100% success rate.
Pathfinder: success
Spirit: success
Opportunity: success
We got another method that got...
Mars 2: crash
Mars 3: too hard touchdown resulting in fault, essentially crash.
Mars 6: crash
Viking 1: success
Viking 2: success
Mars Polar Lander: Crash
Deep Space 2: crash
Beagle 2: crash
Phoenix: success
3 successes in 9 tries. 33% success rate.
Yet they insist on the method that fails twice as often as succeeds, and disregard the one that didn't fail even once by now.
45 5F E1 04 22 CA 29 C4 93 3F 95 05 2B 79 2A B2
You are assuming that all the failures are equal and that each failure means total failure. Spacecraft are not designed that way. Some failures are mere inconveniences/annoyances, where others may be classed as loss of mission failures. Some parts act as backups to other parts, so both would have to fail before there is a loss of mission. Consider the Apollo splashdowns. The capsule is coming down on three parachutes. It actually needed only two.
When our name is on the back of your car, we're behind you all the way!
Im sure theres an iphone app for that fine control landing, iphone does have inertial sensors after all.
Liberty freedom are no1, not dicks in suits.