Yes, this really is an amazing rover! But I wonder why they chose such a complicated landing sequence. So many places where things can go wrong.
I hope this rover actually does land successfully - with its RTG power source it could last for decades!
I hope this rover actually does land successfully - with its RTG power source it could last for decades!
The rover is awesome though. They should build 20 of them and send them to all planets and some of the moons as well.
There's too much gravity, too little atmosphere, and we haven't perfected AI. You can't rely entirely on parachutes, the air bags they used on the last few landings won't hold up to something so heavy, and landing with direct use of retrorockets would pretty much require a human pilot to be sure of -- and even if we had a human pilot, the enormous amount of dust it would kick up is problematic.
There are so many new ideas being employed for the first time I don't feel sure it will work. I assume they did several crane drop tests indoors, but I don't know if they did outdoor tests with a chopper attached to the crane module to see how stable the crane platform needs to be and with the crane module using its own rockets (tethered to a tower, maybe) to control its position while a reduced mass rover simulator touches down. Like I said, tons of new ideas, hardware and software that have never been used (and that won't be used together until they get to Mars) that will all have to work perfectly the first time.
Again, I'm all in to sending this rover to Mars, but shouldn't we be sending rovers to the Moon for some time now? These people are much smarter than either you or me, but it doesn't change the fact engineering progresses incrementally and it seems we are jumping up the stairs and skipping steps. I only hope we don't break a leg here.
I am an engineer. We don't like complicated things.
I would be perfectly confident with a device you could trow it out of a plane, that would parachute until a reasonable altitude, engage rockets to hover and lower a rover to the surface a dozen times without incident.
It'll be at least 30 years until we can inspect the crash site to learn what went wrong.
It's like assuming that you can easily swim five miles because you can easily jog five miles.
The idea is that you have to lower a car-sized rover from a hovering rocket-powered platform that has to remain relatively still regarding the ground. On Mars, the platform would use parachutes to slow it down. On the Moon it may not be needed at all, but you would use rockets, if you still needed the hovering platform approach (say, landing a very heavy habitation module).
Throwing the probe out of a plane, letting it descend on parachutes for some time and then making it hover using rockets until it gently deposits a rover on the surface seems a good way to make sure we know how to do all the required steps for a successful deployment on Mars. Lots of important variables are very different - Mars' atmosphere is very thin, so the crane would have to use far more power to slow itself down (or a much larger parachute), but the gravity is lower, so the rover would descend more slowly and it would require less power to hover. There could be some wind, but the forces applied to the vehicle would be different than what would be on Earth (Martian atmosphere is thin, but the winds are faster). The whole operation appears to me somewhat similar.
I think it'd be worth, and relatively easy, to operate a rover on the Moon. Remember we don't always know what we should have learned until after we try. This Mars rover is a huge step. Huge steps is someting engineers should learn to avoid.