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ESA Shows Off Quadcopter Landing Concept For Mars Rovers
coondoggie writes Taking a page from NASA's rocket powered landing craft from its most recent Mars landing mission, the European Space Agency is showing off a quadcopter that the organization says can steer itself to smoothly lower a rover onto a safe patch of the rocky Martian surface. The ESA said its dropship, known as the StarTiger's Dropter is indeed a customized quadcopter drone that uses a GPS, camera and inertial systems to fly into position, where it then switches to vision-based navigation supplemented by a laser range-finder and barometer to lower and land a rover autonomously.
Really, are you sure it isn't Galileo?
Being a European probe, once landed it will open a small cafe serving croissants and excellent espresso.
I should use this sig to advertise my book ISBN-13 : 978-1501515132.
Mars has an atmosphere. Barely - atmospheric pressure is 0.006 earth-atmospheres. Maybe 0.01 if the weather is right and at a low enough point. You'd get bugger-all lift from a 'copter, quad or otherwise. Even in the nice one-third G, that thing isn't flying. It's hard enough getting something down by parachute - those rovers have to be built to take a nasty impact, because even with a huge parachute and low gravity they still hit the ground hard.
yet another landing concept?
How many of these does the public have to fund before NASA admits to simply trying to stay employed, for cripe's sake.
Why not just leave the quadcopter attached to the rover as a single unit? You then would have a rover capable of short hops to move from point to point, over obstacles, etc.. It might also allow a stuck rover to move out of a sandtrap. It could also blow dust off solar arrays. It would provide a lot more flexibility in motion.
The sky-crane maneuver was designed before the quadcopter design paradigm existed and they were simply trying to safely land a large and heavy science rover. The lower density of the atmosphere and the weight of the rover would need to be considered while developing a new design using a quadcopter approach, but I don't see why a sky-crane would be necessary or even desired.
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I hope someone checked that the martian atmosphere has enough density to support the propeller lift...
I hope they plan on deploying a dozen or more GPS satellites to Mars before they try and land this thing.
Given how thin the atmosphere is on Mars the rotors will have to be huge, and spinning at close to Mach 1. cute idea but the ESA might want to stick with proven concepts, like rockets and air bags. Not as original but when your taking about something that costs ~1 billion (pick a currency) you want something that isn't going to make a hole in the ground out of all your hard work.
StarTiger's Dropter
What the hell kind of name is that? Is this Wing Commander?
With the illustrious qualification of having played Kerbal Space Program, it is my considered opinion that the atmosphere on mars is insufficiently dense for a practical application of quadcopters.
If you've never watched "Seven Minutes of Terror," which explains the crazy but successful scheme to lower the Curiousity rover onto Mars, do yourself a favor and go here: http://www.youtube.com/watch?v...
It's the best video the U.S. Government has ever produced.
That that is is that that that that is not is not.
Here is the official press release, which states the real goal of the project:
Starting from scratch for the eight-month project, the Dropter team was challenged to produce vision-based navigation and hazard detection and avoidance for the dropship.
The quadcopter was just a COTS stand-in for testing their software.
Why can't it BE the rover?
Helicopters work well on Earth for several reasons - first, our oxygen-bearing atmosphere means we don't have to carry our own oxidizer, just fuel, which makes it far more mass-efficient. Then our thick atmosphere means you get a lot more lift for a given amount of airspeed.
I have no doubt that you could get a rotorcraft to work on Mars. It's a question of whether it will work better than alternatives - such as the rockets used by Curiosity. But in essence this will have to be a rocket-powered rotorcraft as well - either rocket-like gas generators, or electric motors would be needed to work in the oxygenless environment, and I don't see electric being feasible in this situation. It then comes down to "is it more efficient to use the fuel+oxidizer to turn a rotor at supersonic speeds, or use it as a rocket?"
I'm no rocket scientist, but it seems to me that the simple extra mass of the rotor is a big strike against it being a good alternative to rockets, never mind the thinner atmosphere.
Not dumbassed, but yes, the blade size, shape, and design speed would need to be redesigned for the reduced air density. Challenging, but perhaps not impossible. And there are many examples of turbomachinery that spin happily at hundreds of thousands of RPM.
If it could be done without a major size or mass penalty, this could permit not just a soft landing, but the potential of a hopping or a flying rover.
Left MS Windows for Linux Mint and never looked back!
Vote for Bernie in 2016!
... on completely missing the point. This project is about testing autonomous visual landing site selection and guidance, NOT proposing that quadcopters can fly on Mars. To be fair, the linked article isn't especially clear on that point either.
tell him he can have a 50 year exclusive getting DVDs and geegaws to martian settlers.
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Martian air density says any sort of copter is not going to fly.
The highest atmospheric density on Mars is equal to that found 35 km (22 mi) above the Earth's surface.
You're going the complete wrong direction. If you want to have any change in hell of actually having enough power to get this thing in the air, you need to get your blade loading down, and that means a huge rotor. Huge rotors mean you need to be running low RPMs to keep it subsonic at the tip, and remember that the colder and higher molecular weight atmosphere means the speed of sound is going to be ~30% lower.
I sure don't suspect that. Putting up a GPS constellation is no small task. And here on earth there is a significant Earth bound support network that the GPS network interacts with to keep everything working.
Yes, it seems crazy that a space agency could overlook this. But less crazy than putting an entire GPS system in place. I actually think that this is more likely to be a manifestation of extremely poor journalism. But there is not going to be a GPS system in place over Mars before this gizmo ever attempts to make a landing, and if it really uses GPS in making a landing it isn't going to work.
I'm an American. I love this country and the freedoms that we used to have.
Personally I thought that the 911 drama was the best video the U.S. came up with.
So convincingly for so many people...
To properly test a prototype, you would need to fly a prototype helicopter (probably with very large rotor and very powerful turbine) to 33,000 meters altitude on Earth to test equivalent atmospheric pressures. The current altitude record for helicopters is only 12,442 meters.
There's another major problem posed by Mars. 96% of the atmosphere is comprised of CO2 and there is only trace amounts of oxygen. That means not only would you have to carry fuel, but you would need to carry your own oxidizer as well which adds a lot of weight.
Everything quadcopter now? Still, even if the atmosphere is thick enough to fly a quadcopter (I'm not so sure about that), last time I checked, GPS wasn't deployed around Mars.
LOL.
No one climbs Mount Everest to test high altitude equipment, they use a hypobaric chamber.
As for fuel - batteries would likely be enough for a quick landing.
Still, it's hard to believe they can make it work - my guess is that it will have to have big propellers spinning real fast, to do anything in that atmosphere, even if they are aiming at a low point with most air pressure like http://en.wikipedia.org/wiki/Hellas_Planitia (~0.01% earth atmosphere)
Do you have a hypobaric chamber large enough to test a helicopter in flight? Even if you use a quarter scale model, you need a pretty large chamber. Furthermore a scale model doesn't behave the same as a full size unit.
Oh man that's hilarious lol