JPL's Plan for the Next Mars Helicopter
spectrum.ieee.org
spectrum.ieee.org
Kind of blue-sky - 30kG is heavy, so maybe its all moot - who's going to dedicate that much mass to this project.
Any geology it does, will be contaminated by rotor wash scrubbing the surface material when it lands. Is that an issue? Maybe its a benefit.
Can it really react to sample inaccessible places? What is the response time between capturing an image of a face, and getting a response from Earth saying "take a sample!"? Is it even within the battery life/flight time?
Can it range outside the rover line of sight? What about radio relay to the orbiter? Surely it can't track that itself, especially in flight. That level of independence may be a pipe dream.
I'm in favor of a drone element to the next mission, as long as it doesn't instantly get lost or broken.
I think JPL's idea is that MSH would be a dedicated helicopter mission, rather than piggybacking on some other mission, so it wouldn't be eating up the mass budget of another lander or rover.
Similar to Ingenuity, the flights would be autonomous but the science wouldn't be. MSH would fly up to a cliff face (or whatever), take pictures, land, ask Earth where to sample, and then make a second flight to do the sampling.
MSH would be able to communicate with orbit directly and would not need rover or lander support.
It's quite a simplistic (2d) setup however. I'm not aware of any more complex experiments.
Does that mean it wouldn't be powered by an RTG like the last few missions? Or do you just mean that the MSH will have its own comms independent of a supporting rover/lander?
Whats the power budget for instruments during/after flight?
Not sure what you mean by limited operating time, though- if you mean that MSH has to spend 50% of its time charging, that's true, but relative to a rover, it can travel so much farther and faster that JPL is arguing it more than makes up for it.
if it is delivered by Starship - and timeframe wise i guess it will be so - then there can be tens of those delivered while not being an even the main mission payload.
One thing of note, it’s too cold on Mars for rubber (as far as I can tell). The tires are one part of my robot that wouldn’t work. NASA developed some elastic-mode Nitinol tires that would do the trick.
Hey hey, demonstrating something is simply possible is definitely "doing science".
That's half the battle!
> We were just telling the scientists, think big
"But not too big..." - Every engineer after the first guy.
You've got that backwards:
Perseverance is equipped with a RAD750, which is simply a radiation hardened PowerPC 750 - that is about as general purpose as it gets.
Ingenuity is equipped with a Snapdragon 801, which is an unhardened Qualcomm processor tailor made for cellphones. I doubt anyone could know the degree to which it is "highly specialized" for cellphones without first signing NDAs from multiple parties.
I've always found the most impressive aspect of these programs to be the careful engineering that extends the mission life far beyond the original goals. Ingenuity was engineered to die - on either a cliff face or from radiation poisoning, which isn't interesting - it is wasteful.
And the one of the goals of Ingenuity was to see if a COTS processor could be used on Mars. The fact that it's survived this long is really encouraging.
Whoosh. A radiation hardened PowerPC 750 operates no differently from a PowerPC 750 you'd find on Ebay. You are effectively saying "Yeah, but how many commercial temperature range processors are in use today?!" It is weird, because it is such a silly distinction to point to that you have to actually examine the manufacturer's packaging datasheet to spot the difference. But at the same time you have no problem conflating every processor using IP licensed by Arm Ltd as the same thing... they have at least 20 distinct architectures and it doesn't look like compatibility was ever much of a priority. The larger point being that the powerpc ISA is infinitely more coherent than the fractured mess Arm has going on, which is very likely the product of designers aligning the platform with disposable electronics. Do you really want to see that trend go beyond crappy cellphones designed to be thrown out every other year?
> ...one of the goals of Ingenuity was to see if a COTS processor could be used on Mars.
That has been said - but has never been explained why... because it is such a thoroughly covered concern that has had a huge amount of money spent on developing industry standards and commissioning incredibly comprehensive studies. So this justification is either an oversimplification to the point of being lie, or it is an indictment on their own work (and that of many others) with regard to the effects of radiation on electronic. Does Mars have some new kind of radiation that our highly controlled labs can't replicate? Of course not, it is a nonsensically wasteful way to test our understanding of radiation - at best.
> The fact that it's survived this long is really encouraging.
lol, the processor has no way of self diagnosing internal faults caused by ionizing radiation. That would be like celebrating your lack of cancer while on a smoke break at your job in an asbestos factory - and at the same time bragging about never getting medical checkups.
The RAD750 costs $200k. I doubt the ARM processor in Ingenuity costs that much.
>Do you really want to see that trend go beyond crappy cellphones designed to be thrown out every other year?
I want cheaper rovers and probes, this is NASA's test for viability
>with regard to the effects of radiation on electronic.
You can test shit in the lab all day but eventually you have to test in the field.
>Does Mars have some new kind of radiation that our highly controlled labs can't replicate?
Do we know exactly the levels of radiation on the surface?
>Of course not, it is a nonsensically wasteful way to test our understanding of radiation - at best.
It's a live, in the field test of off-the-shelf components in space craft on a bonus mission unrelated to the main rover. What would be a sensically nonwasteful test of COSTS processors on Mars be?
>the processor has no way of self diagnosing internal faults caused by ionizing radiation
The helicopter flies and takes pictures. It's had 12 flights as of this comment. When it stops working, we'll know how long regular processors can last.
http://www.gaerospace.com/space-exploration/planetary-aerobo...
With a thick atmo, plenty of sun, and not too much heat / cold in the upper layers. Venus is a _great_ place for balloons.
https://www.nasa.gov/vision/universe/solarsystem/venus-20070...
Taking off again can be done over days so you can power it with solar panels if you can’t fit an RTG.
I honestly don’t think winds would be that much of an issue they won’t be strong enough to structurally damage the airship they’ll blow it off sure but not break it apart, and crashing into things isn’t as much of a risk at any reasonable altitudes no buildings no trees, sure there are cliffs and mountains but that can be solved with altitude.
At least one "garage engineer" was selected this last round.
Low gravity means you need less lift, but low gravity also means the weight of the surrounding air is less so you need more volume. I guess that cancels out.
I suspect it's not practical in atmosphere as thin as Mars, but maybe with a light enough or strong enough material it's possible? At any rate, you'd need an enormous volume just to lift relatively small payloads. And, just filling a balloon with hydrogen would probably make more sense in almost any situation.
At least one good thing Mars has going for it in terms of airships is that CO2 is more dense than Earth's atmosphere. Even nitrogen would be a weak lifting gas on Mars (though it's not available in abundance there as far as I know).
Wikipedia has some useful background information: https://en.wikipedia.org/wiki/Vacuum_airship
They found a design that can work with current materials and lift 500kg worth of payload.
>”The tensegrity based design using current materials, accounting for losses due to deflection of the membrane and other factors, is capable of 500 kilograms of payload. If trends in the mass reduction capabilities of the tensegrity beam design continue to higher complexities, which is probable, then implementation of a complexity 4 beam will result in 1 to 1.5 tons of payload capacity. In addition, the tensegrity design has been shown to offer full deployability and can be collapsed for transport to Mars.”
https://www.reddit.com/r/space/comments/lo6k73/what_will_hap...
If there was a dedicated mission for a much larger helicopter, it would obviously be important for it to have a story for weathering these things.
The main issue would be the size of the balloon but honestly if we can make some origami rigid airframe a vacuum airship might actually work.
At that point controlling buoyancy is also less of an issue from a power perspective since you don’t need a large power reserve to land, and when you are on the ground you can wait until you have enough power to create sufficient vacuum in the airship.
Doing some quick math using the ideal shape of a sphere: Mars surface atmosphere is ~1/60th as dense as the Earth's so you'll wind up with 23x the surface area which at the reduced surface pressures of mars you'd be looking at around 15% of the total forces you'd have to resist. For a sphere that might just push it into the realm of possible options but to get to a 'pure' vacuum you need very fancy and heavy pumps that need cryogenic cooling beyond the difficulty of doing this with an actual blimp shape.
Even given the ability to make it you'd likely have issues with the process of getting it there if we're not assembling it in situ.
The winds are to weak because of the thin atmosphere and there aren’t that many things to crash into.
Since helicopters already outcompete zeppelins on Earth, on Mars where helicopters have a factor of 3 advantage over zeppelins, it’ll have an even harder time.
It’s equivalent to a zeppelin at around 100,000 ft at Earth. Possible, but not very practical.
If you would’ve asked people 10 years ago about flying helicopters on Mars plenty of them would say it’s not possible not because the math doesn’t work out, but because of what requirements the math spits out.
I can do the math for a helicopter for galactic hydrogen, it doesn’t mean engineering can make one. However a vacuum airship on Mars is very much possible, it’s just a heck of an engineering challenge but if you want to get to large payloads not to mention any substantial flight time it’s by far more realistic than a helicopter.
A zeppelin could in principle work on Mars, but it'll be worse than a helicopter, all things being equal. Weather balloons can work fine at those air pressures, but they don't control their position.
34% better, in aviation, may easily make the difference between practical and not. In the case of Ingenuity, it appears to have made the difference between a need for custom SotA vs. COTS kit.
What computing could usefully be offloaded to the rover is very limited. Compressing video, maybe, and that just for power budget. I think Ingenuity has >10x MIPS than Perseverence.
Reduce Ingenuity’s flight time by 10%, and it would still be practical.
You clearly have not kept up on CPU design. ISAs are the same, but implementations have been through 3 generations.
You clearly have not kept up on motor performance. Nothing theoretical has changed, but COTS motors are much better executed than could be had 10 years ago.
You clearly have not kept up on solar performance. While absolute efficiency has not increased much, weight has. Furthermore, and of greater moment here, dust-repellent coatings have improved.
The aggregate improvement is much better than 34%.
Is that what would happen? How does the embed de-embed itself? How does the reeling in not end up pulling the drone closer to the cliff?
ofc we don't already know the exact composition and hardness of said cliff walls, so your question stands.
You'd probably already need some batteries anyway as I'm guessing that the transient spikes in power usage would probably exceed any RTG you could fit in a helicopter anyway.
Strontium-90 produces 0.95W/g, where Pu-238 produces only 0.57 W/g. So, it takes only 3/5 as much, by weight, to produce the same heat as a Pu-238 RTG, although it takes 4.5x as much room. Room is relatively cheap on spacecraft, vs. mass.
This makes me wonder why they use Pu-238 RTGs in spacecraft at all. Maybe because it lasts a bit longer?
https://en.wikipedia.org/wiki/Radioisotope_thermoelectric_ge...
"This incident resulted in the NASA Safety Committee requiring intact reentry in future RTG launches, which in turn impacted the design of RTGs in the pipeline."
You might argue it's about risk, but that didn't seem like such a huge deal when we tried to make nuclear cars and planes back in the 50s. RTGs are just incredibly inefficient, and properly shielded fission reactors are incredibly heavy.
https://en.wikipedia.org/wiki/Dragonfly_(spacecraft)#Design_...
https://news.ycombinator.com/item?id=18947350 ("NASA May Decide This Year to Land a Drone on Saturn's Moon Titan")
https://news.ycombinator.com/item?id=20337042 ("A technical look at the Dragonfly Titan mission")
>"Flight on Titan is aerodynamically benign as Titan has low gravity and little wind, and its dense atmosphere allows for efficient rotor propulsion.[35] The radioisotope thermoelectric generator (RTG) power source has been proven in multiple spacecraft, and the extensive use of quad drones on Earth provides a well-understood flight system that is being complemented with algorithms to enable independent actions in real-time.[35]"
You _can_ use nuclear power similar to the rover if the lift / weight isn't prohibitive. That means a bigger copter in a thicker atmosphere and lower gravity. Since the power is generated by temperature gradients, cold helps too.
Perfect for Titan.
It’s gonna be 30kg =P
…
I’ll show myself out.
Sounds like the 1st Cav in Vietnam - cower, you tentacled Martian fiends!
Opening the image in another tab then zooming then I suddenly wonder why on Earth this is required. I know it's not malice, but there must millions of people with sub 20:20 vision who don't want to enable the screen magnifier when pinch is ALREADY A THING.