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Nasa will send helicopter to Mars to test otherworldly flight

bbc.com

101–110 of 128 posts

Re: Nasa will send helicopter to Mars to test otherworldly flight

#101
post #77

Didn't see any mention on how it will be powered, are batteries even feasable? I thought just keeping rovers warm enough to operate was quite energy consuming.

It looks like it's only going to do one brief flight, so yes, batteries probably are feasible. I'm not sure if it would require more power or less power than on Earth though since gravity is lower but so is air density for the blades to act on.

Re: Nasa will send helicopter to Mars to test otherworldly flight

#102

Does this make any sense? Isn't Mars' atmosphere much thinner than Earth's? Wouldn't that count against using rotary wing crafts?

It’s about 1% the density of earths atmosphere. The craft would have to be light and have large blades, but that doesn’t seem impossible. The light atmosphere means huge blades could still spin fast without issue. It’s not easy but this is NASA we’re talking about. They made a sky crane to drop a Mini Cooper sized rover on Mars before.

Also gravity is about a third of Earth's, so that might help a little bit.

Re: Nasa will send helicopter to Mars to test otherworldly flight

#103

Earlier quoted context omitted.

Simulating dust kick-up would be easier than constructing a "low gravity" room.

It isn't too hard to simulate low gravity, all you need to do is move a large aircraft in the appropriate parabolic pattern. My understanding is that this is already how NASA trains astronauts for zero-g environments, and how weightlessness is done in space movies. Adjusting the path to match Mars gravity should not be difficult.

It might not be realistic to fly a pressure vessel large enough to simulate the low atmospheric pressure as well as the low gravity. There are probably also safety concerns; the rotors on serious R/C helicopters store enough energy to basically decapitate a human and these are probably somewhere in that neighborhood given the requirement to generate lift in Mars' atmosphere.

Re: Nasa will send helicopter to Mars to test otherworldly flight

#104

Does this make any sense? Isn't Mars' atmosphere much thinner than Earth's? Wouldn't that count against using rotary wing crafts?

All heavier-than-air flight on Mars is subject to the same issue, but it's presumably still more efficient than using rockets. If it works, it works.

I expect the real problems would come in scaling it up; I doubt a typical helicopter rotor/head assembly would hold together under the high head speeds needed on Mars (or you could maybe use very long blades, which comes with its own problems).

Re: Nasa will send helicopter to Mars to test otherworldly flight

#105

Earlier quoted context omitted.

That's what I thought too. But they've been designing this for years; so it might have started before drones got as popular as they are. I mean, drones are just a new name for hobby aircraft. People typically associate drones with quad-copters, but people were flying tiny helicopters next to their small replica remote aircraft for decades. I realize the FAA has official designations for what is a drone (and a lot of…

> drones are just a new name for hobby aircraft With the minor notation that hobby aircraft are permitted in some national parks, while drones are prohibited in all. The Parks Service operates a number of model aircraft airports in some national parks. (I'm not moaning about the perceived inequity with the "drones;" just pointing out a curiosity. I've hated drones ever since they started ruining my ability to peacefu…

I'll give an upvote for this. Not the most polite way of putting it, but I appreciate keeping it real.

It's a UAV if you want to get back into the subject matter we're discussing though. I do wonder how well it'll do in the Martian atmosphere, especially if it gets caught charging in a sandstorm.

Re: Nasa will send helicopter to Mars to test otherworldly flight

#106

Earlier quoted context omitted.

Mars is 140 million miles away from earth on average. Even if you could detect signals from GPS satellites on earth they would all be at a single point in the sky. However, that does bring up an interesting idea. Maybe rovers could navigate using the position of the stars? It doesn't require you to launch 4+ GPS satellites into martian orbit.

I don't see why not - automatic celestial nagivation systems are already a thing on earth, you basically have a system that uses a camera to look at the sky and it gives you an accurate position - most military planes use it as backup in case GPS ever goes down.

Good read: The Island of the Day Before by Umberto Eco

TL;DR you need to see the stars and you need to know what time it is

Re: Nasa will send helicopter to Mars to test otherworldly flight

#107
post #73

Earlier quoted context omitted.

A little more recent: https://youtu.be/oJGJEepIOt0?t=38 It's from Red Planet (2000): https://www.imdb.com/title/tt0199753/

Even more recent: https://youtu.be/vacjOrVqesM?list=RD7Oq-ClZ8Gbs&t=299 From the series Mars (2006) - https://www.imdb.com/title/tt4939064/ .

That looks like the very same heli-drone! I had not heard of the series, thank you.

Re: Nasa will send helicopter to Mars to test otherworldly flight

#108
Looks like a more efficient and much faster way to explore the area if they can solve the thinner atmosphere but, if their missions are autonomous and it seems that can't be modified in real time, what happens with the mars storms?

I hope that they have a software to take measures if the air pressure or the light levels change suddenly.

Couldn't the differences in temperature between shadowed and sunny areas create turbulences?

Re: Nasa will send helicopter to Mars to test otherworldly flight

#109

Earlier quoted context omitted.

That's what I thought too. But they've been designing this for years; so it might have started before drones got as popular as they are. I mean, drones are just a new name for hobby aircraft. People typically associate drones with quad-copters, but people were flying tiny helicopters next to their small replica remote aircraft for decades. I realize the FAA has official designations for what is a drone (and a lot of…

> drones are just a new name for hobby aircraft With the minor notation that hobby aircraft are permitted in some national parks, while drones are prohibited in all. The Parks Service operates a number of model aircraft airports in some national parks. (I'm not moaning about the perceived inequity with the "drones;" just pointing out a curiosity. I've hated drones ever since they started ruining my ability to peacefu…

To me what makes a drone a drone is the control system algorithm that keeps the aircraft stable. I thought "model aircraft " had to be operated by a sufficiently skilled operator to keep it from crashing. Whereas "drones " automate this skill and present a very simple, dummed down interface such as "go left, turn around, descend" etc

Re: Nasa will send helicopter to Mars to test otherworldly flight

#110
post #73

Earlier quoted context omitted.

A little more recent: https://youtu.be/oJGJEepIOt0?t=38 It's from Red Planet (2000): https://www.imdb.com/title/tt0199753/

Even more recent: https://youtu.be/vacjOrVqesM?list=RD7Oq-ClZ8Gbs&t=299 From the series Mars (2006) - https://www.imdb.com/title/tt4939064/ .

Damn, past my edit window. I mean 2016, not 2006.
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