[HN Gopher] After six months on Mars, NASA's tiny copter is stil...
       ___________________________________________________________________
        
       After six months on Mars, NASA's tiny copter is still flying high
        
       Author : Pikkie
       Score  : 305 points
       Date   : 2021-09-06 07:07 UTC (15 hours ago)
        
 (HTM) web link (phys.org)
 (TXT) w3m dump (phys.org)
        
       | kokey wrote:
       | I think people who fly tiny whoop quadcopters would find the
       | description of a 1.8kg copter as 'tiny' quite amusing. I'm
       | guessing the primary driver for the weight is the power to lift
       | this in the thin atmosphere, secondary to that the weight of the
       | strong materials used to make it durable.
        
         | azernik wrote:
         | Not just the power to keep it up, but also the rotors. Not sure
         | how heavy Earth quadcopter rotors are as a proportion of total
         | vehicle weight, but the Ingenuity ones are absolutely enormous.
        
       | ForHackernews wrote:
       | This is a good lesson in under-promise, over-deliver. NASA seem
       | to be masters of that technique.
        
         | ISL wrote:
         | I saw first-hand how it comes to pass, from collaborating with
         | NASA engineers years ago.
         | 
         | In order to ensure that a critical mission-goal is met, with,
         | say, 95% confidence, every subcomponent must be _much_ more
         | reliable, as there will be many ways to fail. The net effect is
         | that often the overall perceived reliability turns out to be
         | much better than the requirement.
         | 
         | This is especially so for systems that have already achieved
         | some measure of success, as a number of those subcomponents
         | will have already done their jobs completely.
        
         | dtech wrote:
         | I suspect it's because of a solid physical engineering culture.
         | They probably have enormous safety factors and redundancies or
         | work-arounds, since you can't change anything physically once
         | it's launched.
         | 
         | So if things go alright, those provide lifespan far beyond
         | specifications.
        
         | Camillo wrote:
         | Eh, at this point it's a boy crying wolf situation. Whenever
         | there's a new space gizmo you know they're going to say "we
         | only designed it to work for eight minutes", and then six
         | months later it'll still be chugging along, because the actual
         | design life was measured in years.
         | 
         | They could at least say "the doodad is designed to work for two
         | years, but there's a 5% chance that it'll be DOA, because so
         | many things can go wrong in space". That would be more
         | realistic.
        
           | dugmartin wrote:
           | The problem is people hear what they want to hear. Much like
           | telling a PM that a project is probably going to take 2 weeks
           | but might extend to 2 months. Guess which number they are
           | going to remember and hold you to?
        
           | II2II wrote:
           | Not really. They are putting experimental hardware into an
           | environment that is not well understood. It is also being
           | done by very public facing organizations with very large
           | budgets. They basically have to guarantee that they will
           | deliver what they say they will deliver. From a public
           | relations standpoint, it may even be easier to justify a
           | complete failure than an 80% success since a string of 80%
           | successes will look like incompetence while a few complete
           | failures are quickly forgotten.
        
           | fsckboy wrote:
           | you don't deserve to be downvoted (this place is ridiculous)
           | because saying that there's a "boy crying wolf" aspect is
           | true, and it was the whole point of learning that story which
           | point apparently some people missed.
           | 
           | but there is also a position I'd like to point out between
           | the one most people here are taking ("NASA over-engineers
           | every part individually to avoid failures")
           | 
           | and yours ("here's our reasonably expected life, but could
           | come up short")
           | 
           | and that is: they need to set a bar that evaluates a
           | reasonable amount of science they need to accomplish to
           | justify the budget.
           | 
           | It's not the minimum number ("crashed in flames but we
           | learned some things")
           | 
           | and it's not the gloriously optimistic number ("this thing's
           | still going after 12 years, it's really worth it!")
           | 
           | and it's not a fake marketing expectations number ("we'll
           | fake the budget numbers so we can razzle dazzle by blowing
           | past the expectations")
           | 
           | rather it's just, "for X hundred million we expect to spend a
           | month taking pics in every direction and gathering and
           | analyzing some rocks from different promising places, and
           | that mission alone is worth it" because that's what congress
           | is approving
        
           | JohnJamesRambo wrote:
           | It is always an exercise in horrible estimates and it gets
           | really tiresome. If you always greatly exceed the estimate
           | (by orders of magnitude!) it wasn't a good estimate, it was
           | PR. I assume NASA has real estimates they use internally. No
           | one could be this bad at it and still have a job there
           | surely.
        
         | cheschire wrote:
         | I always took it to be a budget defense method since they never
         | get as much money as they as for, and have to expertly manage
         | expectations to ensure they continue getting the "little" money
         | they do.
         | 
         | Little is quoted because it's a hotly debated and subjective
         | word.
        
         | amelius wrote:
         | > This is a good lesson in under-promise, over-deliver. NASA
         | seem to be masters of that technique.
         | 
         | And Tesla seems to be master of the exact opposite technique
         | with Autopilot.
        
           | mchusma wrote:
           | It's far from clear that NASAs general conservative nature
           | has been a good thing relative to a more risk-tolerant one.
           | If we accepted more failure, could we accomplish a lot more?
           | 
           | Particular with SpaceX on the scene, it's time to start
           | rethinking risk, because launch costs will be so much lower.
        
       | robin_reala wrote:
       | One of the most interesting things about Ingenuity is the amount
       | of standard open-source code used. Github has a badge for if you
       | contributed code to a project used by it, and they put up an
       | explanatory page at https://github.com/readme/featured/nasa-
       | ingenuity-helicopter.
        
         | jorgesborges wrote:
         | And a list of the repositories. Very cool.
         | 
         | https://docs.github.com/en/account-and-profile/setting-up-an...
        
         | eric__cartman wrote:
         | Having that badge would give anyone very cool bragging rights
         | about how they wrote software that's running on Mars.
         | 
         | It makes perfect sense that NASA used a lot of open source
         | software for this. If some high quality, widely used and tested
         | code already exists, why not use it instead of trying to
         | reinvent everything?
        
           | robbedpeter wrote:
           | I once spent a week troubleshooting a pair of routers that
           | were part of a NASA Mars mission. They were using firmware
           | over a decade old at the time, which was causing issues with
           | the internet facing edge devices, which had automatically
           | updated a few weeks prior, and that started causing massive
           | packet loss.
           | 
           | There were redundant paths with redundant hardware, and the
           | node I worked on wasn't particularly important, but I got a
           | taste of what the engineers and scientists at NASA must live
           | for, the sense of contributing to something historic,
           | profound, and deeply human.
           | 
           | The fix was simple at the end, a firmware rollback and
           | disabling further updates, and most of the time was consumed
           | in conversation and carefully assessing each step and action,
           | but I count it as a high point in my career. Just to touch
           | the edge of it was special.
           | 
           | The people whose code and engineering get sent to space are
           | contributing to the betterment of mankind, literally making
           | the universe a better place. Kudos to those guys. To write
           | code that's part of a critical system is a meaningful in a
           | way
        
           | dimator wrote:
           | I highly doubt it's running on Mars. For one thing, sibling
           | comment has a list of repos that have the badge, and it's a
           | lot of python packages. I suspect it's more along the eath-
           | based infrastructure and data processing side of the
           | equation. Still a pretty cool get, though.
        
             | stavros wrote:
             | Well, I just checked and I got the badge! Go me! I wonder
             | which of the tens of open source libraries I've written was
             | actually used by NASA!
             | 
             | Oh, the badge tells, you... Hmm, let's see, it says
             | "attrs". That's not mine, I must have submitted a PR at
             | some point, let me find it.
             | 
             | Ah, right. I changed "serious business aliases" to
             | "serious-business aliases" in the README.
             | 
             | You guys are all welcome.
        
               | Teknoman117 wrote:
               | Mine was some CMake fixes for cURL when using it as a
               | subproject in a "superbuild" project.
        
               | stavros wrote:
               | Still better than adding a hyphen...
        
               | dima55 wrote:
               | I literally worked on the heli, but my badge came from a
               | documentation patch to numpy :)
        
             | heavyset_go wrote:
             | Apparently some of the non-mission critical experimental
             | components that were sent to Mars run your standard Linux
             | systems with some Python software, as well. I believe I
             | heard in an interview with a NASA engineer that they were
             | using Python for ML and scripting.
        
           | burundi_coffee wrote:
           | > If some high quality, widely used and tested code already
           | exists, why not use it instead of trying to reinvent
           | everything?
           | 
           | This is precisely the spirit of free software and the
           | motivation behind movements like public money public code.
           | Govermnets immensely overpay for software (projects).
        
       | fao_ wrote:
       | Jesus, has it been six months already? What is this hell world.
        
         | Cthulhu_ wrote:
         | It's less than four months until 2022.
        
           | [deleted]
        
         | ant6n wrote:
         | Wait, you're on Mars too?
        
       | Incerto wrote:
       | It's been six months already? How time flies...
        
         | secfirstmd wrote:
         | Well it's been nearly 11 months in Martian time... :)
        
           | gshubert17 wrote:
           | But Mars takes 1.88 earth years to make one orbit. So, 6
           | earth months is closer to 3/12 of a Martian year.
        
         | unknownOrigin wrote:
         | Yea, same reaction, I had to double check it's true. Damn,
         | we're getting old.
        
         | dTal wrote:
         | Only 4 and a bit months since its first flight though, when it
         | was all over the news.
        
       | unnouinceput wrote:
       | Quote: "NASA is planning to retrieve those samples during a
       | future mission--sometime in the 2030s. "
       | 
       | Not if Musk gets his rocket filled with 100 people on Mars in
       | next years. Then you'll have a better way to do science on that
       | soil.
        
       | coldcode wrote:
       | I wonder what the upper limit on weight will be. The article
       | mentioned multiple kilograms being possible in the future.
        
         | _joel wrote:
         | Have a swarm instead/as well, much more capable at covering
         | range.
        
         | zokier wrote:
         | JPL is planning already much bigger copters:
         | 
         | > The current MSH concept has a mass of about 31 kg and a total
         | diameter of just over four meters, with six rotors each
         | sporting a quartet of 0.64 meter blades
         | 
         | https://spectrum.ieee.org/the-next-mars-helicopter
        
       | [deleted]
        
       | neals wrote:
       | Do we have any amazing pictures from it?
        
         | stohk wrote:
         | Ingenuity only has one downward facing color camera and b/w nav
         | cam. None of them are particularly amazing but its just a tech
         | demo. You can see all the images here,
         | https://mars.nasa.gov/mars2020/multimedia/raw-images/
        
           | nisegami wrote:
           | Seeing color pictures from another planet's surface is one of
           | the things that always fills me with awe.
        
         | MayeulC wrote:
         | Someone has used the low-FPS, downwards-pointing color camera
         | plus photogrammetry to reconstruct the flight environment:
         | https://www.youtube.com/watch?v=tX89Y766D_M
        
         | jffry wrote:
         | Depends on your threshold for amazing. It's a lot of pictures
         | of rocks since they're cameras for navigation. On the other
         | hand they're aerial views of another planet taken by a
         | helicopter during autonomous flight.
         | 
         | One notable photo was on Ingenuity's third flight, where it
         | happened to get the Perseverance rover and landing area
         | together in one frame:
         | https://mars.nasa.gov/resources/25862/ingenuity-spots-persev...
         | 
         | There is also the NASA blog just covering Ingenuity, which has
         | some more notable photos along with explanations:
         | https://mars.nasa.gov/technology/helicopter/status/
        
         | amelius wrote:
         | Half of the pictures on the NASA website are rendered mockups.
         | I don't know which ones are real anymore.
        
           | tokai wrote:
           | They always write in the image description if it is an
           | illustration or not.
           | 
           | Or use the raw image library
           | https://mars.nasa.gov/mars2020/multimedia/raw-images/
        
         | ilkkao wrote:
         | It could hover near the rover and take nice photos. But I'm
         | sure NASA doesn't want to take a collision risk like that.
        
       | danhor wrote:
       | Maybe after the shift from space-grade parts to commodity parts
       | in (some) satellites, this will mean the same for parts of future
       | mars missions. A Snapdragon 801 as used here is certainly much
       | cheaper, easier to work with and powerful than anything space-
       | grade.
        
         | solarkraft wrote:
         | It's also such great marketing. I wonder why the Zigbee
         | alliance doesn't communicate more that it's used for
         | communication between the rover and the helicopter.
        
           | mschuster91 wrote:
           | Probably because they'd get ridiculed to beyond the solar
           | system that they can make a Mars rover fly, but it's a
           | nightmare to get two Zigbee products from different vendors
           | to talk to each other.
        
         | pkaye wrote:
         | However they still use a rad-hardened FPGA to run some of the
         | critical aspects. This paper discusses a lot of the internals.
         | 
         | https://rotorcraft.arc.nasa.gov/Publications/files/Balaram_A...
        
         | holoduke wrote:
         | Anyone knows if the copter suffer already from issues and
         | reboots already?
        
         | enkid wrote:
         | I believe it is much cheaper to put something in LEO then it is
         | to get it to Mars, so I don't know if the economics of Mars
         | Missions have fundamentally shifted to cheaper probes the way
         | they have for satellites.
        
           | XorNot wrote:
           | I suspect we're limited more by communications capability
           | then anything else: pretty much a hand-held radio will reach
           | up to LEO if someone's listening (short-wave definitely does
           | and that's off-the-shelf at consumer prices pretty much).
           | 
           | Whereas Mars requires the Deep Space Network to reasonably be
           | able to maintain communications - so your very cheap probes
           | still need super-highgrade radios to be useful (the landers
           | for example still generally pack an antenna that can reach
           | all the way back to Earth even when they use uplinks - the
           | helicopter is relaying via the lander).
           | 
           | What we're missing on Mars is reliable communications for
           | probes: there's no common backhaul to Earth that you can just
           | hook into. But I'd be willing to bet that's coming: if
           | Starlink works on Earth, there's no real reason it shouldn't
           | work on Mars. At which point you can go with the "swarm of
           | cheap hardware" idea because it can hand off the need for the
           | power, hardware and logistics and backing to communicate
           | inter-planetary.
        
             | [deleted]
        
             | jvanderbot wrote:
             | > Whereas Mars requires the Deep Space Network to
             | reasonably be able to maintain communications - so your
             | very cheap probes still need super-highgrade radios to be
             | useful
             | 
             | That's not technically true. They maintain fancy radios
             | that can reach Earth as a backup. Data transfer is done via
             | the Mars Relay network.
             | 
             | https://mars.nasa.gov/news/8861/the-mars-relay-network-
             | conne...
             | 
             | Ingenuity uses this as well.
             | 
             | > if Starlink works on Earth, there's no real reason it
             | shouldn't work on Mars.
             | 
             | Ground-to-low orbit comms relays have been in operations
             | for half a century. And decades at Mars already. Starlink
             | is for high throughput communications from ground to ground
             | on the same planet with always-on connectivity and global
             | coverage. Their sattelites are engineered cheap and
             | replenished with cheap lift from SpaceX. Totally different
             | problem calculus at Mars and doesn't address "backhaul" to
             | Earth.
             | 
             | You'd need longer-lived high throughput optical terminals
             | or better, preferably at Areostationary orbits. Checkout
             | work by Briedenthal and Edwards on the matter.
        
         | jessriedel wrote:
         | A bigger effect is that, by the time the next helicopter is
         | ready to launch, SpaceX Starship is likely to drop the cost of
         | delivering cargo to Mars by an order of magnitude or more. That
         | will massively disrupt the mass vs. capability trade-offs we
         | see in all Martian rovers and aircraft.
        
         | DrNuke wrote:
         | It really depends on the space environmental work conditions,
         | though... that's the fundamental trigger for space grade
         | quality.
        
         | _joel wrote:
         | There's also some RAD hardened components to check for bit-
         | flips and restart the hardware that quickly it can do it mid-
         | flight.
         | 
         | Here's the full paper.
         | https://trs.jpl.nasa.gov/bitstream/handle/2014/46229/CL%2317...
        
           | ryandrake wrote:
           | I wonder how much hardware marketed as "space grade" (or
           | whatever the terminology is, I'm just a layman) is actually
           | as hardened using these techniques and redundant as you'd
           | expect. Or are they simply certified because the
           | manufacturer's process went through some checkboxes. In the
           | aviation world, for some components, the difference between
           | aviation grade and non- is 1. cost and 2. a Certificate of
           | Conformance from the manufacturer that says "this thing is
           | provably aviation grade, trust us bro."
        
           | flavius29663 wrote:
           | That is so smart. I know we're talking about NASA, but I am
           | still in awe.
           | 
           | I read a bit of the paper, it's actually even more redundant
           | than what you said:
           | 
           | - snapdragon is only used for higher level functions of the
           | flight: The SnapdragonTM processor has a 2.26 GHz Quad-core
           | SnapdragonTM 801 processor with 2 GB Random Access Memory
           | (RAM), 32 GB Flash memory, a Universal Asynchronous Receiver
           | Transmitter (UART), a Serial Peripheral Interface (SPI),
           | General Purpose Input/Ouput (GPIO), a 4000 pixel color
           | camera, and a Video Graphics Array (VGA) black-and-white
           | camera. This processor implements visual navigation via a
           | velocity estimate derived from features tracked in the VGA
           | camera, filter propagation for use in flight control, data
           | management, command processing, telemetry generation, and
           | radio communication. The SnapdragonTM processor is connected
           | to two
           | 
           | - for flight control they use 2 (redundant) automotive chips
           | from Texas Instruments: TMS570LC43x high-reliability
           | automotive processor operating at 300 MHz, with 512 K RAM, 4
           | MB flash memory, UART, SPI, GPIO.
           | 
           | - these are all controlled by a radiation hardened board, the
           | 3rd level of redundancy
        
             | _joel wrote:
             | They also used a $129.99 altimeter from Garmin (Lidar-
             | Lite-V3), no fancy fancy.
             | https://www.sparkfun.com/products/14032
             | 
             | edit: https://www.garmin.com/en-US/blog/general/garmin-on-
             | mars/
        
         | darkwater wrote:
         | I'm not a space expert at all but my wild guess is that doing
         | small, careful tests for consumer grade hardware (and software)
         | to be used on Mars is a way to lower costs of a possible future
         | settlement, by leveraging economies of scale here on Earth.
        
         | johnwalkr wrote:
         | I actually just wrote the policy on this topic for a space
         | project I work on.
         | 
         | It really depends. It's often not cheaper to use such commodity
         | stuff unless you can tolerate a lot of risk. A lot of normal
         | and automotive components are used in space, but it's mostly
         | simple stuff that's relatively easy to qualify. A snapdragon
         | cpu will basically never be fully qualified as a single
         | component because you cannot control each state, let alone test
         | it in each state (I am oversimplifying but bear with me). What
         | you can do is apply overcurrent detection, external watchdog
         | timers, redundancy and other techniques to mitigate the effects
         | of radiation.
         | 
         | Then, you can almost fully test that mitigation in theory but
         | not really because it will cost you millions of dollars with
         | huge technical risk and the part will probably be obsoleted or
         | made by a different fab next time you need it. So, you choose
         | older proven easily-hard stuff where you can, or for anything
         | mission critical or related to safety. Better to just buy the
         | $200k rad hard cpu and save your millions.
         | 
         | Then, you are left with only bonus items such as this
         | helicopter that simultaneously do not have many reliability
         | requirements (because it's not mission critical) and are not
         | possible with traditional space grade technology due to
         | performance requirements.
         | 
         | "Easier to work with" is only true when you take risks too.
         | Yeah, you can start developing right away using a devkit and
         | Linux, but if you find your project needs reliability or safety
         | requirements, you may find you are spending person-years of
         | software engineering time if it's even possible at all. You
         | might be required for the system to be deterministic and avoid
         | dynamic memory allocation, for example.
         | 
         | Interestingly, students making cubesats don't "know better"
         | yet. And while the overall failure rate is probably bad on a
         | per mission basis, it's probably good on a per kg or per dollar
         | basis. There's a ton of cubesats and cubesat payloads that have
         | raspberry pi's inside for Leo missions.
        
         | nisegami wrote:
         | From my limited knowledge of electronics-in-space, isn't ECC
         | memory a hard requirement to correct for bit flips due to solar
         | radiation/particles? But DDR5 having ECC be standard across the
         | board may make this a non-issue.
        
           | Cthulhu_ wrote:
           | Kinda, yes, but at the same time, servers here on earth have
           | moved away from (expensive) ECC in favor of resilient
           | software, disconnected services (job queue based) and
           | redundancy. Cheaper to have a dozen computers that sometimes
           | break than three with lower risk (but they still break).
        
             | zitterbewegung wrote:
             | For consumers no but for things like large simulations or
             | even deep learning you want to have ECC memory.
             | 
             | Intel only enables it on Xeons but AMD doesn't officially
             | support it on their consumer chips but sometimes it works.
        
               | my123 wrote:
               | It's locked down on AMD customer APUs, only not
               | forcefully disabled on AMD customer CPUs that do not have
               | integrated graphics. (Ryzen PRO parts have it officially
               | supported)
        
       | 10GBps wrote:
       | Interesting craft in that it's essentially just a larger version
       | of the R/C toys you can buy. I wonder how they tested the blade
       | design. Did they fly it at 100,000ft on Earth?
        
         | Cthulhu_ wrote:
         | Didn't it also use Zigbee (for home domotics) as a control
         | protocol?
        
         | mkl wrote:
         | Veritasium has a good explainer about the development and
         | testing: https://www.youtube.com/watch?v=GhsZUZmJvaM
        
         | dtgriscom wrote:
         | Four words: really big vacuum chamber.
        
         | londons_explore wrote:
         | I assume it was tested in a pressure chamber on earth to
         | simulate the pressure and composition of Mars atmosphere.
         | 
         | Obviously it wouldn't be able to fly in the pressure chamber
         | due to increased gravity, but by suspending it on elastic you
         | can still test that the blade functions as intended.
         | 
         | The only bit you can't really fully test is the constants for
         | the control loops in the flight control algorithm, but I assume
         | they chose them with a lot of stability margin.
        
           | _Microft wrote:
           | It did fly in the vacuum chamber. It was a tethered flight
           | and the difference between Earth's and Mars's gravity was
           | compensated by an appropriate pull being applied to the
           | tether.
        
           | SideburnsOfDoom wrote:
           | > I assume it was tested in a pressure chamber on earth... by
           | suspending it on elastic you can still test that the blade
           | functions as intended
           | 
           | They did exactly that. NASA has a big (adjustable) vacuum
           | chamber for this kind of purpose.
           | 
           | This comment links to video:
           | https://news.ycombinator.com/item?id=28432811
        
         | TotempaaltJ wrote:
         | Just a vacuum chamber:
         | https://www.youtube.com/watch?v=tMCJGfwj3rY
        
         | [deleted]
        
       | Causality1 wrote:
       | It's incredible to me they managed to get it to fly at all
       | considering how thin mars' atmosphere is.
        
       | foobar1962 wrote:
       | > ... still flying high
       | 
       | Shirley you must be joking!
        
       | jackcosgrove wrote:
       | Can't wait for a successor to Ingenuity to capture aerial video
       | during its flights.
        
       | juliendorra wrote:
       | About the size: the blades are really huge "in person" (in VR :-)
       | 
       | I added both the Perseverance Rover and Ingenuity to our VR
       | puzzle game Peco Peco[0], and I was totally surprised both times
       | by how bigger than I thought they were. (Players can assemble the
       | puzzle for Ingenuity at full scale, and at both full scale and
       | 1/3rd of scale for the rover)
       | 
       | So if you have a VR headset, I highly suggest to find a way to
       | discover Ingenuity at full scale in VR.
       | 
       | [0] https://pecopecogame.com/
        
       ___________________________________________________________________
       (page generated 2021-09-06 23:00 UTC)