Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

The Mars Helicopter Is Online and Getting Ready to Fly

universetoday.com

Post reply on HN
Print view View original

181–190 of 265 posts

Re: The Mars Helicopter Is Online and Getting Ready to Fly

#181

Post by simcop2387 »

xadhominemx wrote: post #180
ChuckMcM wrote: post #150

Earlier quoted context omitted.

And given the density of Venus' atmosphere, here is a fun thought experiment. It may be possible to make 'titanium' balloons for longer term operation. The would work by creating the balloon envelope on earth, have a sealing mechanism that you activated in orbit so they had vacuum inside. And then drop them into the atmosphere. Same idea a glass floats on fishing nets[1] except with titanium (so they can withstand th…

Venus’s atmosphere is 100x denser than earth’s, so you could just seal the metal balloons at sea level pressure and it wouldn’t really make a difference. Or you could seal them in a vacuum on earth. Not sure why you would need to feel them in space.

Weight and volume. The air has weight so it'll cost more to launch. The volume would also make them more difficult to launch. Assembling or unfolding in space near earth would allow you to make them larger and inspect them before they leave for venus.

Re: The Mars Helicopter Is Online and Getting Ready to Fly

#182

Post by cosmonaughty »

NikolaeVarius wrote: post #49
laydn wrote: post #25

Why is nobody worried about the helicopter crashing to the rover and possibly destroying a science instrument? How far will the helicopter be from the rover?

Because NASA isn't full of idiots.

Right. They are very clever. They are clever enough to have all of you believing this AVR enhanced cartoon was a real Martian landing. If those helicopter blades spin 40x faster than a real chopper at sea level air pressure on earth, the turbulence alone would disintegrate the flywheel and blades and destroy the whole thing. So how did they test it? Let a experiment explain it: https://m.youtube.com/watch?v=8Cx9mNnky2U

Re: The Mars Helicopter Is Online and Getting Ready to Fly

#183

Post by CamTin »

JKCalhoun wrote: post #76
samfisher83 wrote: post #38

Earlier quoted context omitted.

In general the older nodes work better for radiation and other cosmic forces. https://en.m.wikipedia.org/wiki/Radiation_hardening That's why they don't use the latest and greatest in the space.

Can't all of the radiation issues be mitigated with proper shielding of the electronics?

https://media.ccc.de/v/36c3-10575-how_to_design_highly_relia... is a really interesting talk by some guys from CERN who have to design chips for use in particle accelerators and other physics experiments where they must survive unusually hostile radiation environments.

Re: The Mars Helicopter Is Online and Getting Ready to Fly

#184

Post by dragonwriter »

cosmonaughty wrote: post #182
NikolaeVarius wrote: post #49

Earlier quoted context omitted.

Because NASA isn't full of idiots.

Right. They are very clever. They are clever enough to have all of you believing this AVR enhanced cartoon was a real Martian landing. If those helicopter blades spin 40x faster than a real chopper at sea level air pressure on earth, the turbulence alone would disintegrate the flywheel and blades and destroy the whole thing. So how did they test it? Let a experiment explain it: https://m.youtube.com/watch?v=8Cx9mNnky…

> If those helicopter blades spin 40x faster than a real chopper at sea level air pressure on earth, the turbulence alone would disintegrate the flywheel and blades and destroy the whole thing. So how did they test it?

The obvious method would be a large vacuum chamber, evacuated enough to simulate martian atmospheric pressure.

Google it and, yes, that's exactly it.

https://en.m.wikipedia.org/wiki/Ingenuity_(helicopter)#Testi...

Re: The Mars Helicopter Is Online and Getting Ready to Fly

#185

Post by minitoar »

simcop2387 wrote: post #181
xadhominemx wrote: post #180

Earlier quoted context omitted.

Venus’s atmosphere is 100x denser than earth’s, so you could just seal the metal balloons at sea level pressure and it wouldn’t really make a difference. Or you could seal them in a vacuum on earth. Not sure why you would need to feel them in space.

Weight and volume. The air has weight so it'll cost more to launch. The volume would also make them more difficult to launch. Assembling or unfolding in space near earth would allow you to make them larger and inspect them before they leave for venus.

I could see reusing an empty fuel tank or something as a cute way of doing this.

Re: The Mars Helicopter Is Online and Getting Ready to Fly

#186

Post by cosmonaughty »

dragonwriter wrote: post #184
cosmonaughty wrote: post #182

Earlier quoted context omitted.

Right. They are very clever. They are clever enough to have all of you believing this AVR enhanced cartoon was a real Martian landing. If those helicopter blades spin 40x faster than a real chopper at sea level air pressure on earth, the turbulence alone would disintegrate the flywheel and blades and destroy the whole thing. So how did they test it? Let a experiment explain it: https://m.youtube.com/watch?v=8Cx9mNnky…

> If those helicopter blades spin 40x faster than a real chopper at sea level air pressure on earth, the turbulence alone would disintegrate the flywheel and blades and destroy the whole thing. So how did they test it? The obvious method would be a large vacuum chamber, evacuated enough to simulate martian atmospheric pressure. Google it and, yes, that's exactly it. https://en.m.wikipedia.org/wiki/Ingenuity_(helicopt…

The link I posted points to a YouTube video of a vacuum chamber reduced to "Martian" pressure. It should have been obvious that my question was rhetorical, and that I provided the answer. Watch the YouTube video and compare it to the AVR cartoons that NASA is giving for millions of dollars per day.

Re: The Mars Helicopter Is Online and Getting Ready to Fly

#187

Post by dragonwriter »

cosmonaughty wrote: post #186
dragonwriter wrote: post #184

Earlier quoted context omitted.

> If those helicopter blades spin 40x faster than a real chopper at sea level air pressure on earth, the turbulence alone would disintegrate the flywheel and blades and destroy the whole thing. So how did they test it? The obvious method would be a large vacuum chamber, evacuated enough to simulate martian atmospheric pressure. Google it and, yes, that's exactly it. https://en.m.wikipedia.org/wiki/Ingenuity_(helicopt…

The link I posted points to a YouTube video of a vacuum chamber reduced to "Martian" pressure. It should have been obvious that my question was rhetorical, and that I provided the answer. Watch the YouTube video and compare it to the AVR cartoons that NASA is giving for millions of dollars per day.

Your post was sneering at the idea of it being real, and I generally don't click on video links without a clear idea of what they are (because video is a low-information-0er-time, high-emotional-engagement medium, and experience has proven that it's almost never worth doing) and I'm even less likely to do so with the implied content from the rest of your post.

Re: The Mars Helicopter Is Online and Getting Ready to Fly

#188

Post by KMag »

jcun4128 wrote: post #179
KMag wrote: post #177

Earlier quoted context omitted.

Not sure about the counter-weights, but without a tail rotor, I'm pretty sure it requires either a collective on both levels, or else software to navigate properly when the body is spinning, and some mechanism to allow it to safely land while the body is spinning. The torque to spin the rotor changes with the blade angle, so to keep the counter-rotating torques balanced, they need to control blade pitch on both. I su…

Yeah I don't know enough myself. I wonder if you could use drag change on one and rpm change on the other, maybe balance out in terms of lift. But yeah maybe those pointy things are just weights/for aerodynamics.

Oh, I'm pretty sure you want them spinning at the same speed so their angular momenta cancel out, in case a wind gust puts a torque around a horizontal axis on the system... cross product of angular momentum with applied torque...

Re: The Mars Helicopter Is Online and Getting Ready to Fly

#189

Post by dntrkv »

xwdv wrote: post #175
spullara wrote: post #167

Earlier quoted context omitted.

Highly recommend looking at the specs of the helicopter. It masses just 1.4kg. Each blade is 35g!

Basically a DJI Phantom 4. Edit: Phantom 4 is 1.3 kg and blades are 45g

Except Ingenuity's blades are 4 feet long.

Re: The Mars Helicopter Is Online and Getting Ready to Fly

#190

Post by w33dwizrd »

samfisher83 wrote: post #38
birktj wrote: post #23

One of the things I find really cool about Ingenuity is how it is in large based on consumer hardware. The main processor is a Snapdragon 801 running Linux which communicates with Perseverance using the Zigbee protocol [1]. Perseverance on the other hand uses a RAD750 from 2001! If successful I hope this can lead to more modern hardware for these kinds of missions in general. [1] https://en.wikipedia.org/wiki/Ingenui…

In general the older nodes work better for radiation and other cosmic forces. https://en.m.wikipedia.org/wiki/Radiation_hardening That's why they don't use the latest and greatest in the space.

These projects also have long development periods, they want to be sure everything works so they can't just sub things out at the last minute. So you end up with a system using 10 year old tech.

Will be interesting when missions are being launched utilising the tech of today, like rad hardened neuromorphic chips https://www.businesswire.com/news/home/20200902005406/en/Bra...

Post reply on HN