Also, this makes Mars the second planet that uses Linux more than Windows as noted by the tweet in the linux below. :-)
https://www.theverge.com/2021/2/19/22291324/linux-perseveran...
Some info from Wikipedia:
> The rover's computer uses the BAE Systems RAD750 radiation-hardened single board computer based on a ruggedized PowerPC G3 microprocessor (PowerPC 750). The computer contains 128 megabytes of volatile DRAM, and runs at 133 MHz. The flight software runs on the VxWorks operating system, is written in C and is able to access 4 gigabytes of NAND non-volatile memory on a separate card.
Wow, such a great testament to The Unix Philosophy of building small, modular, focused tools that can be combined together to do all sorts of interesting and more complex tasks. I'm sure no one imagined using these utilities from a helicopter to retrieve rover logs to aid in diagnostics, but here we are. What a cool story.
See EDLCAM in https://link.springer.com/article/10.1007/s11214-020-00765-9
If you're remembering correctly, then I'm misremembering in that this has essentially a Snapdragon chip and not a rad hardened CPU at all
[1] https://en.wikipedia.org/wiki/Ingenuity_(helicopter)#Avionic...
It all makes rational sense. It just feels weird to think about Python running on Mars before there's even people there.
(I'm kidding, the badging system is funny)
It does bode well for sending cheaper "nice to have" experiments on missions, though.
NASA absolutely does have some incentive to find savings in control hardware and software.
Finally, while Ingenuity does use a non-hardened Snapdragon, many other of its critical electronics components are still rad-hardened. The FPGA and dual MCUs (that actually do the low level control and I/O I assume) are both rad hardened. In addition, the COTS components that were used where screened by NASA for their performance in radiation.
The Snapdragon is really just there to control the radio, and do image processing. Critically, these are functions that have -some leeway- for timing, giving the option to just restart the Snapdragon if a watch dog detects a problem.
All of this to say is that rad-hardening isn't going away, but will probably stick around in many critical niches. What Ingenuity absolutely do is validate that modern COTS processors have a role to play in radiation elevated environments, including in semi-critical applications.
HN is dominantly a web/SW crowd plus some mobile frontend, and "it uses a Snapdragon" gives many a wrong idea. In embedded device projects a lot of time is spent planning and designing around a heavy compute element running Linux like this, especially if the device has a safety concept or other mixed criticality concerns. It will have a substantial moat around it.
On HN if you say "systems architecture" most folks go "Oh you mean like, whether we use microservices?". In embedded, while there is a lot of overlap and analogues, it's also all of the above, plus power state management and other aspects. It's not very shiny, but that profession makes all your cars, airplanes and alien planet multicopters.
edit: from another comment: https://news.ycombinator.com/item?id=39081718
It looks like it's just a couple of (important) components that can handle the quirks of not being radiation-hardened, but it's still significant.
> He got a quote back for $120,000. “Elon laughed,” Davis said. “He said, 'That part is no more complicated than a garage door opener. Your budget is five thousand dollars. Go make it work.’”
For LEO you can scoot by pretty easily with non-hardened solutions and better systems engineering and software. For deep space you'll need to be more clever.
Here's the background:
There were numerous ways in which SpaceX's strategies diverged from space industry norms, and almost all of them had direct implications for the cost of its launch systems. First, whereas most aerospace companies give their designs to myriad third-party contractors who create the hardware for them, SpaceX produced roughly 80% of its launch hardware inhouse. SpaceX builds its own motherboards and circuits, vibration sensors, radios and more. In most industries vertical integration increases the costs of firms by not enabling them to benefit from competitive bidding between efficient suppliers. In the aerospace industry, however, the entrenchment of norms around using parts specialized for the space industry ("space grade"), and the bureaucratic rules defined by government contractors, had kept supply costs high — very high. SpaceX decided instead to build many of its own parts, or to buy parts not considered "space grade" and modify them to achieve "space grade".For example, rather than paying $50,000 to $100,000 for an industrial-grade radio, SpaceX was able to build its own for $5,000, and shaved 20% of the weight off at the same time.
SpaceX's willingness to produce their own parts came as a shock to suppliers. For example,Tom Mueller recounts a time when he asked a vendor for an estimate on a particular engine valve: "They came back [requesting] like a year and a half in development and hundreds of thousands of dollars. Just way out of whack. And we're like, 'No, we need it by this summer, for much, much less money.' They go, 'Good luck with that,' and kind of smirked and left." Mueller's team created the valve themselves, and by summer they had qualified it for use with cryogenic propellants. "That vendor, they iced us for a couple of months," Mueller said, "and then they called us back: 'Hey, we're willing to do that valve. You guys want to talk about it?' And we're like, 'No, we're done.' He goes, 'What do you mean you're done?' 'We qualified it. We're done.' And there was just silence at the end of the line. They were in shock." As noted, a big factor driving savings at SpaceX is that it often builds its components out of readily available consumer electronics rather than equipment alreadydeemed "space grade" by the rest of the industry. Twenty years ago "space grade" equipment would have had far superior performance characteristics compared to consumer electronics, but today that is no longer the case-standard electronics can now compete with more expensive, specialized gear. For example, at one point SpaceX needed an actuator that would steer the second stage of the Falcon 1. The job fell to engineer Steve Davis to find the important part, and since he had never built a part like that before he sought out suppliers who could make it for them. Their quoted price for the device was $120,000. As Davis recalls, "Elon laughed. He said, 'That part is no more complicated than a garage door opener. Your budget is five thousand dollars. Go make it work.'"20 Davis ended up designing an actuator that cost $3,900. Another example is provided by the computers that provide avionics for a rocket. Traditionally NASA's Jet Propulsion Laboratory bought expensive, specially toughened computers that cost over $10 million each to operate its rockets. Musk told engineer Kevin Watson that he wanted the bulk of the computer systems for Falcon 1 and Dragon to cost no more than $10,000. Watson was floored,noting, "In traditional aerospace, it would cost you more than ten thousand dollars just for the food at a meeting to discuss the cost of the avionics."21 Watson was inspired by the challenge, however, and ended up creating a fully redundant avionics platform that used a mix of off-the-shelf computer parts and in-house components for just over $10,000. That same system was then also adapted for use in the Falcon 9.
About the actuator: Steve Davis, the twenty second hire of SpaceX, needed an actuator that would trigger the gimbal action used to steer the upper stage of Falcon1. He went to find some suppliers and got a quote a $120,000. “Elon laughed”. Davis said. “He said, ‘That part is no more complicated than a garage door opener. Your budget is five thousand dollars. Go make it work.’” Davis spent nine months building the actuator and the final actuator approved by Musk ended up costing $3900.
Seems like they don't include the engineering time in the part cost calculations - so cheating a bit!I've experienced building something in-house that is far better than what you could otherwise get. Back in the 00's I wrote a JavaScript framework because the existing ones were all crappy in a variety of ways. Even as a one-person effort (and I'm no 10x engineer) I could write something that was wayyy better in a bunch of important ways (albeit not pretty enough design). My work was engineered better than the open source and commercial frameworks that I evaluated/used. Better loading, better recovery from network and other errors, better memory behaviour, better size, better speed, better integration, better diagnostics, better browser support, better user interface, customised for our needs. It did exactly what we needed for our project and mostly worked flawlessly.
So while "strictly speaking" they planned for three 90 second flights. There was the unstated assumption that it'd be used for much more than that as long as it actually worked effectively.
https://www.planetary.org/space-policy/cost-of-the-mars-expl...
Or maybe have a helicopter that can move the rover with the equipment to different locations.
https://ieeexplore.ieee.org/abstract/document/9843501
In short, future designs target ~30kg heli, 5kg payloads. Other designs by collaborators are closer to 20kg. It's probably possible to transport a few of these on the existing lander technology, which would be awesome.
The scholar.google.com keywords you want are "Mars Science Helicopter" and a good touchpoint author is T. Tzanetos or S. Withrow-Maser
Actually it could be like 50 of them. Plus some ground robots to put together solar farm. And wooh... we get the first extra terrestrial permanent base
untested possible landing vehicles ...
in which case, yeah, you have a lot of robots.
For the solar farm assembly case, It's actually a lot easier to have a teleoperated robot doing the work, a few astronauts in orbit doing the operation / construction. In the case of building things, you want as much space / weight landed to be the thing being built, not the builders, per se.
Not sure if Nasa has said yet which roles they see for future Mars helicopters. The initial idea behind Ingenuity was to use them as scouting vehicles for rovers. Of course rovers improved a lot too, with better autonomous driving. But with a Mars rover driving about 100 meters/yards per day scouting helicopters are still useful.
Maybe we will also see Helicopters carrying more instruments themselves. But I imagine in the beginning that's mostly better imaging instruments. Weight is still an issue for flying things, no matter the planet. But maybe we will see some future missions that instead of a car-sized rover and one tiny helicopter have a fleet of helicopters with a small support-rover for exploring wider areas.
But yeah having more helicopters might be feasible - for surveying the surface.
(Listed as 4 pounds on this official fact sheet) https://mars.nasa.gov/files/mars2020/MarsHelicopterIngenuity...
I’m not an aeronautical engineer, so I guess what I’m asking is if there is some problem scaling up flying machines in an extremely thin atmosphere?
On earth rotor sizes are limited by the speed at the wing-tip. Once you make the rotor too long the tips start approaching supersonic speeds, giving you all kinds of weird mach effects. To make matters worse, the speed of sound is about 30% lower on Mars compared to near earth's surface.
https://ieeexplore.ieee.org/abstract/document/9843501
In short: 30kg heli, 5kg payloads. Other designs by collaborators are closer to 20kg. It's probably possible to transport a few of these on the existing lander technology, which would be awesome.
The scholar.google.com keywords you want are "Mars Science Helicopter" and a good touchpoint author is T. Tzanetos or S. Withrow-Maser
Ames and JPL were still collaborating on this when I worked there.
Sojourner (1997): 11 kg
Spirit & Opportunity (2004): 185 kg
Curiosity (2011): 899 kg
Perseverance (2020): 1,025 kg
(Of course, all of NASA's long-term plans for Mars would be completely disrupted if Starship lowers the cost-per-kg of delivering equipment by two orders of magnitude, which arguably is likely.)
Even the combo is probably too much complexity. A heli with good imagers, spectrometers, and the ability to cart soil samples would be fantastic.
Titan is such a wonderful place for a nuclear powered helicopter. Much better than rover/submarines/floaters, IMHO. A balloon would also have been excellent, but the extra mobility from helis is going to be amazing.
IMO NASA wanted to try to deal with the sort of 'oh boy... another rover' fatigue and saw the drone as a way to spice things up with some passable science arguments behind it, and a relatively minimal cost. Further supporting this is that the helicopter wasn't an initial part of the plan - it was strapped on at the 'last minute', speaking in government time. In any case, I would comfortably wager against us seeing more drones in future missions, at least to Mars.
Does it? I thought the helicopter was just solar powered.
I should add though that the prospects of the parasites in Congress properly funding such a complex mission seem pretty low for now.
I heard this line in my mind with Professor Fansworth's voice.