Simulation of the Mars Science Laboratory Sky Crane

An anonymous reader points us to Gizmodo for a fascinating video of NASA's Sky Crane. "When I read that the UFO-looking Mars Science Laboratory's aeroshell would use a floating crane — called Sky Crane by NASA — to softly land the rover on Mars, I couldn't believe it. Now, watching this hyper-realistic NASA simulation, I still can't believe how the whole thing works. I don't know about you, but the whole operation mesmerizes me to no end."

Comments

Why not use what works?

[ryanisflyboy]

Why does NASA have to spend money on new untested methods? If the old baloon method worked well for two previous rovers, why not use it again? It is hard to beat a 100% success rate. Does anyone know why they want to use this over other methods?

The sysadmin in me says: The more moving parts, the greater the chance something will break.

Re:Why not use what works?

[corsec67]

True, but how much does a triangular pyramid covered with self-inflating balloons weigh? Plus it had the hinged ramps that would fold down, so the old landing method wasn't completely without complex stuff.

Re:WTF: Hyper-realistic?

[Anarchitect_in_oz]

I think it's to cover all the storytelling camera movements and focus effects, that go above and beyond the simulation of the concept itself. More fun to watch that way. Like news is more interesting with handheld cameras and fast cuts.

Re:This is needlessly complicated and HERE is why:

[the_other_chewey]

Even in their most recent plan for this Mars descent, their first mode of descent is to drop the module like a stone, using elaborate and expensive heat shielding to protect the even-more-expensive gear. But maybe -- just maybe -- they could take a lesson from Spaceship One and just take their time getting this thing down to the ground.

Sorry - but you have no clue. Mars' atmosphere at the surface has about 1% of the Earth's density, making something like aerodynamic flying impossible.
There simply isn't any other way than "dropping like a stone" - even on their parachutes, the rovers did exactly that. Those parachutes were supersonic, and their
main purpose was trajectory stabilization (although they did of course contribute to the braking).

Go read this article already linked above for a well written explanation about why
landing on Mars is actually very hard and cannot in any way be compared to landing on Earth.

Why the crane part?

[Somegeek]

I'm OK with everything up until they start winching the lander down under the crane. How is that better than sitting the rover on top of the retro rocket module, hovering, then landing, and having the rover drive off the top of the lander?

The number of failures that could happen to the winching system seems nuts; a line might not lower, or at the wrong speed, or a line could tangle, or a side to side oscillation while descending, or a cable not disconnect, and if any of these go wrong, you have no time to fix it.

Re:Why the crane part?

[ChrisA90278]

I think some one figured out that a winch is ligher weight then a folding ramp. You have to remember that this next rover is the size of a car. Think about how you'd make a folding ramp that would allow a car to drive off a lander. The winch is very compact and light

A ramp carries a risk too. It would need a set of motoers and gears to make it unfold. If there is anything in spacecraft that will fail it is those kinds of moving parts and they depand on batteries that have beenin space for a year.

The winch could be a simple fiction device. Not a motor, just a spool of cable that is pulled open by the weight of the rover and some kind of friction device to reduce th speed that the cable can unroll.