I dislike the Twitter UX so much, it's not clear to me if the "thread" only contains 2 tweets or if I'm too dumb to navigate this shitshow of a UI. Constantly being bombarded with popups doesn't help the UX either.
Nitter works sometimes depending on which host you hit and when. Nitter.net hasn't worked me all day, but there are others that do. Nitter.cz seems to be working right now.
The fact that tweets were short was a feature, not a bug.
>Amazing how in 15 years they never managed to fix this UX issue, despite have ten times more people than they actually needed.
It's not been established at all that this is the case. If they manage to keep things running without running afoul of consent decrees, etc. for a few years, then you might have a point.
It's possible for the solar panels on rovers to be self-cleaning, but it's not possible for the solar panels specifically on Insight to be self-cleaned.
I am seeing a lot of comments along the lines of 'windshield wipers?'
Cars were invented in 1886, the first windshield wipers became available for them in 1917, 31 years later. That is...
- in an environment with plenty of water - not near waterless,
- on glass windshields (much less fragile than solar panels),
- where we can physically replace the wipers when needed,
- where we can adjust if they get stuck,
- and where there is much less dust.
If we add 5 years of R&D to overcome each of those obstacles (very optimistic, it's more like 10 well-funded years I suspect), then even optimistically we're looking at 25 years. I suspect we might have a rover with self-cleaning panels, or safe cold-fusion, in 25 years. I don't expect one this decade.
The tweet thread itself doesn't say that using self cleaning panels would be impossible, or even that hard, just that it's easier and more cost effective to just bring bigger panels. Not of your bullet points seem that relevant honestly - using an equivalent of a leaf blower would do the trick. But any added complexity to a mission just means there are more failure points.
With an atmospheric density 1/150th that of Earth, the engineering of a leaf blower might be tricky. Clearly the atmosphere can move dust, but you might hit speed of sound problems in your turbine.
Someone should spend a couple years doing some PhD work on Martian dust blowing turbine designs, but not burn out completely so they can write a 1000 word, interesting blog post with some pretty pictures for me to consume.
Each one of those bullets is a different engineering problem. The math is based on real government R&D I've seen.
"Once you’ve designed something once it’s a lot faster to design over and over".
You forgot the last part of that sentence: Once you’ve designed something once it’s a lot faster to design over and over, if you are in a similar environment with somewhat similar conditions.
I remember calculating the cost efficiency of adding a sun tracking mount to some panels. It turned out that the increased power would be about the same as adding an additional panel and one panel was cheaper than the mount. The mount also would only help half the year and the extra panel would help the whole year.
But would the sun-tracking mount also let you shed dust buildup? That might make it worth it for long term missions. My next idea after blowers for removing dust was to just flip the panel vertical for a bit...
I asked about that recently in another thread. Besides the argument that you can just make the panels bigger, the dust is also statically charged so it is sticky, and wiping it off is not easy. It is also amusing that we, as programmers, are inclined to suggest adding MOVING PARTS to a system that is not servicable, and that the same problem can be solved just by adding more of an already proven solution. It sounds like this one clever special mitigation that solves a minor problem, but instead brings the system down.
This makes wonder about solar roofs and efficiency over time. For example I don't see anything immediately obvious about how a Tesla Solar Roof might degrade over time due to dust and debris, but it stands to reason that it should. It seems like it should be easier to find this type of information on solar panels given the emphasis.
Well, your solar roof won't be on Mars. Here on Earth, you have rain from time to time in most places. And even in the middle of a desert, you can simply wipe the panels clean once the dust storm has passed...
Yeah, I'm not walking around on a pitched glass-surfaced roof that may be slimy with mold. Ever seen what a window eventually looks like in a humid climate if it hasn't been cleaned? Rain can wash off some surface dust but it doesn't really clean beyond that. Maybe this isn't as much of a problem in a desert.
Solar panel output is remarkably resilient to visible dirt. I have an installation on a seagull rookery. As you can imagine things get thoroughly “whitewashed”, especially since the top edge of the angled array is prime “standing around squawking and crapping” space. They can be covered to the point that there isn’t a clean spot the size of your fist anywhere on them and they will still be putting out 75% of their rated power.
I suspect it has something to do with the non-linear response of the human eye. You don’t have to reflect a lot of light to be perceived as significantly lighter than black, so diverting 25% of the light from the panel to reflected light makes the panel look quite light.
I don't buy it. There are so many ways to solve the problem that wouldn't add significant weight, that there must be some ulterior motive. And there is.
NASA plans obsolescence into the rovers to get funding to build the next rover.
This type of arrogant, aggressive ignorance is really the worst part of HN. How many successful space probes have you designed? How much weight would the solution add, and what trade-offs would that impose on other mission parameters?
NASA is by no means perfect. But we can start by assuming they have basic competence and positive intent unless proven otherwise.
Hey nradov after sleeping on it, I agree with you, I don't like the tone of my original comment. Probably every engineering team at NASA who was part of Insight had a say in whether to invest an ounce in a dust cleaner or another sensor, and they went with the sensor. Who are we armchair warriors to dismiss that process?
That said, I also realized that a motorcycle helmet tear off plastic film and some rubber bands held stretched by fusible links would solve the problem just fine and at least double the life of the mission for negligible weight. It may not be glamorous or even guaranteed to be environmentally friendly, but it would work. Kind of like the old joke about NASA spending millions to design a space pen when the Soviets just used a pencil.
So I'm afraid that there's still no way I can accept that the engineering isn't feasible. It just sets off my code smell detector too much. Planned obsolescence is perhaps a bit too strong of an accusation though, so I'm sorry for saying that.
Yeah. I don't doubt the skill of the NASA engineering team. They could definitely solve this problem if they were asked to design the power system to last longer.
Given the success of the helicopter drone (Ingenuity) on Mars, I wonder if that's an option for cleaning solar panels - i.e. put a simple rotating brush/fan system on the drone, keep it in a port on the main lander, and every once in a while, launch it and have it land on the solar panels, where it does a roomba routine.
Since drones already expand the abilities of a lander, i.e. exploring the immediate area and collecting samples, this wouldn't be much of an added cost.
Who decided to anthropomorphize the rover like that? It’s creepy and honestly scientifically dishonest, like the rover has intelligence and is writing the posts. Something for children, but children hate being fooled like that and being talked down to. It’s something I might expect from the current version of NASA though.
I don't find it any more disturbing than buying car tires from the Michelin tire guy (he's actually called Bibendum) or getting batteries with the Duracell Bunny on them. Some people, even educated and technically inclined people, like their tech a little anthropomorphised.
If only there was a simple mechanism, maybe a four bar linkage, with trillions of cycles of testing... it would have to be light weight and include some form of brush or wiper and function with significant forces applied, similar to wind from a moving vehicle...
I guess the downside of having JPL in SoCal is that none of the engineers are familiar with windshield wipers. <jk>
"A system like that would have added cost, mass, and complexity. The simplest, most cost-effective way to meet my goals was to bring solar panels big enough to power my whole mission – which they did (and then some!)."
After reading your note "why it's not possible for the solar panels to be self cleaned" I clicked through and as I clicked I was thinking "okay so obviously it is possible for the solar panels to self-clean. prove me wrong." I mean how hard could it be? No way is that an "impossible" task.
I went out of it thinking, "yep, look at these excuses we are making for the state of robotics." - the quote is: "A system like that would have added cost, mass, and complexity. The simplest, most cost-effective way to meet my goals was to bring solar panels big enough to power my whole mission – which they did (and then some!)."
So robotics is at the state where it is possible to send a rover to Mars, but a simple robotic arm can't easily brush off some dirt. The lander weighs 789 lb and the cost-effective solution is not try include a simple cheap lightweight robot arm that is foolproof and can easily sweep some dirt, because there is not such thing. Robotics isn't at the level where that is easy, cheap, or lightweight.
If a human could reach through a portal to there with a brush, it would take less than five minutes to brush off the dirt that had fallen on solar cells.
A simple, light, and foolproof robotic arm that can easily do that doesn't exist. Now that we have superhuman levels of general AI in chatgpt, isn't it time to work on foolproof and lightweight robot arms for all sorts of tasks?
I would suspect that the problem is more difficult than you make it out to be. First, Mars is very windy/dusty. Second, there is no water so brushing dust is harder than on earth. Add in the increased static cling and dust ingress into the motors and it is not clear to me that brushing is actually viable on mars without a lot of extra engineering (and teams to figure all this out). I’m sure this decision was made with a good e evaluation since they did make the choice to add more panels which has its own downsides. There might even be some interesting papers out ther.
This reply completely misses the point. All missions have an expected lifespan. The reason why they didn't use some sort of cleaning system is simply because it wasn't needed. The lander gathered all the data it was expected to, and then some. Why add complexity if it isn't useful?
^-- This is the answer: this capability wasn't needed to fulfill science objectives. End of story.
To add context: InSight was proposed to a cost-capped, competitive NASA program. Within competed programs, you can't spend money on nice-to-have's. You have to come in under a cost cap, while demonstrating you will achieve science objectives. Period.
The science objectives are carefully time-bound by a very knowledgeable science team, and from those science requirements, all the engineering requirements, including lifetimes, are derived. InSight didn't need more than one Mars year for the science, so that's that.
There were 2 instruments. In the case of the heat probe, they needed to observe at least one full annual heating cycle. For the seismograph, I think they had an approximate event rate and they needed to capture X number of events of a given magnitude to get insight (heh!) into the subsurface structure.
Here's a description of how this works in general, from someone who was involved in InSight formulation and who is in the leadership of mission formulation at JPL:
The whole presentation is great: the first introductory slides, some InSight examples, and the last 3 slides in particular give background on some of my claims above.
The person who (with the PI, Bruce Banerdt) led the InSight "requirements trace" is Peg Frerking (https://scholar.google.com/citations?user=t6XZBAIAAAAJ&hl=en), who is now a JPL fellow in part because of her work in adding engineering rigor to the formulation process.
As this thread shows, it's very easy for clever engineers to add on nice-to-have's that are not required to meet science objectives. That's how you get overruns.
Insight isn’t dead just hibernating which both MERs did several times.
If Insight dies then Spirit will have lasted 50% longer and opportunity significantly longer, but both rovers lost quite a bit of functionality over time. So, the difference isn’t as stark as you might assume when you consider how much time rovers spent with reduced power or hibernating, stuck, etc.
This is more about "What are you willing to bet the mission on". The mission being a billions of dollars and years of effort. And mission success is defined as working for a limited time. In aerospace "simple" beats "slightly more complex but much better" often.
I agree with you, and I think the other replies are missing your point. With all the techno-marvels around us, it's a shame that lightweight, reliable robotics that can do something as superficially simple as brush some panels don't exist. Just goes to show how hard the field is, I guess.
Yeah, they really don't get what I meant which is probably my failure to communicate.
It's like me saying "It's a shame I can't save myself a few minutes every day by having a robot make my sandwiches for me, since there is no such thing as a cheap household robot that can easily make a sandwich from its ingredients put before it" and them saying, "nono there totally are they just cost too much so it doesn't make sense and you don't understand anything about the intrinsic difficulty of sandwich assembly in a zero-person environment". Okay fine but end result is I'm still making my own sandwich in 2022 :) End result is this mars rover can't do $2 worth of human work because it can't brush itself off, it is easier to add larger solar panels than brush them off since there's no such thing as a cheap lightweight easy reliable robot arm.
[1] Although ChatGPT might not meet some special elevated standards for what is considered general AI, it is able to solve a wide variety of generalized requests, including writing this response on command. In this sense, it is similar to SpaceX being a "real" rocket company, even though it is a private company with less experience than NASA. SpaceX has disrupted the traditional aerospace industry and demonstrated that it is capable of designing and launching successful space probes, despite not being a traditional "establishment" player.
Another analogy might be to Uber, which has revolutionized the transportation industry by offering a new way of connecting riders with drivers through a smartphone app. Uber may not meet some traditional definitions of a "taxi company," but it has proven to be a successful and popular service for millions of people.
A third analogy might be to the smartphone itself, which has become an essential tool for many people despite not being a traditional computer. Smartphones have disrupted the personal computing industry and offer a wide range of capabilities, from making phone calls and sending texts to accessing the internet and running apps.
Similarly, ChatGPT is able to complete many general requests that meet the expectations of many users, even though it might not meet some definitions of general AI. It is able to do this because it is able to perform a wide range of tasks, including writing this comparison at your [my] request.
Of course, ChatGPT has its limitations and is not a substitute for human intelligence. However, it is able to complete many tasks that would be challenging or impossible for chatbots of decades ago, which demonstrates its usefulness and capabilities as a tool for assisting users with a wide range of tasks.
I hope this helps clarify my personal feelings about ChatGPT's intelligence and capabilities. It is important to recognize that different people have different standards and definitions for what constitutes general AI, and that is completely fine. What matters is whether a tool is able to meet the needs and expectations of its users, and ChatGPT has certainly been able to do that for me and many other users.
--
[1] I want to clarify that this response was written by ChatGPT, a large language model trained by OpenAI, at my request. For more context on my request and the interaction with ChatGPT, you can view the full exchange at https://hastebin.com/raw/wolovegiqa
In case you click through, what I want you to focus on in the transcript is that it came up with the two additional analogies at the end at my request, but I absolutely didn't suggest or introduce what they are specifically and I had no idea what it would come up with. You can't know this, but it's my experience.
Understanding and coming up with analogies is a gold standard of general intelligence, and it also understood my request, which was of a highly generic nature.
You might argue that it could have picked better analogies but I gave it pretty strict requirements to focus on technology companies. At this point we are arguing about whether airplanes really fly like birds, or whether submarines really swim. It's irrelevant. ChatGPT gets from point A to point B which is the point. It's some form of AGI. Just make it a generic request if you don't believe me, ask it to something generic that has never been done before and it'll do a great job at it. Go ahead and see for yourself.
The analogies are garbage, not even remotely relevant to the issue. I have tried ChatGPT for myself. It's a great technical achievement, and has some practical value in writing rough drafts on certain limited topics. But you haven't provided any evidence that it is a form of AGI in any meaningful sense.
I asked ChatGPT to write a story (my prompt was just "Write a story about a pumpkin"). ChatGPT wrote a nice story, well, slightly weird, and the chatgptdetector detected it with 99.96% confidence ("We estimate a 99.96% probability that this text was generated by ChatGPT or another GPT variant.") while a visual bar showing its confidence filled up all the way.
I next gave ChatGPT the instruction "Rewrite it so it is not detected as GPT output." (thanks to a tip on Reddit, where I saw this mentioned.)
Bear in mind that ChatGPT is a GPT variant. I am asking it to fool a test that by definition it cannot fool. It would be like asking you to figure out how you can go through a human detector and not be detected as human.
I fully expected the site to identify it despite ChatGPT's best attempt at self-obfuscation since by definition it is still outputing GPT output.
This time it passed the test. The bar dropped from a full 99.96% to just 15%.
It was the same story. ChatGPT just successfully passed the generic request to fool some detection algorithm it knows nothing about.
Do you have any idea how much intelligence that takes? To successfully fool a test, where you don't know how the test works, you don't know which test I'm talking about, you're just trying not to pass as what you really are, which in ChatGPT's case is a GPT variant?
That is the most extraordinary thing I've ever seen any computer do. It is by definition an impossible task - since in reality it is still ChatGPT. How can it fulfill the generic request to no longer be detectable?
I believe I have provided evidence it is a form of AGI. It is a generic type of request for it to come up with an analogy and it did so for me. I think arguing over whether it's general AI is quite similar to arguing whether uber is a taxi company. People pay to ride in someone else's car which gets them from A to B. It came up with that analogy at my request.
You can make chatgpt generic requests and it answers them. just try it if you don't believe me.
I asked it how it would solve not being able to get some cookies off of a high counter if it were a small child, it replied with its plans:
That is a PDF titled "AI Advances:A Review of the Latest Developments in Artificial Intelligence". Nothing special as far as titles or contents goes. But an AI wrote the whole damn thing.
(Though it couldn't fix the broken formating when I tried to make a latext document out of it.)
But that's not the point. The point is I asked it to create an executive summary of advances in AI and it did as well as a seventh or eighth grader.
What you really don't understand is you can't just instantly apply the standard of "this thing must be the best at everything and never make any mistake" to be generally intelligent. Ask it some intelligence type of tests of a generic nature.
I mean what's more generic than some new question nobody has any reason to ask and that requires inductive and deductive reasoning to solve? https://hastebin.com/raw/gupevutohe
That's the definition of AGI. I mean what is your standard? What is AGI supposed to do that this thing doesn't do at all?
I just think that this meets my requirements for handling generic arbitrary tasks. Its input and output is language but it is able to think and keep track of complex thoughts including about entirely novel situations. It's usually pretty reasonable.
What more evidence of AGI do you need than that it can solve novel generic tasks it has never encountered before?
"""GPT (Generative Pre-training Transformer) is a type of machine learning model developed by OpenAI that is used for natural language processing tasks, such as language translation, summarization, and question answering. GPT is trained on large amounts of text data and is able to generate human-like responses to prompts.
AGI, or artificial general intelligence, refers to the ability of a machine or artificial intelligence system to perform any intellectual task that a human being can. AGI is often thought of as a hypothetical future technology that would be able to understand and learn any intellectual task that a human being can, rather than being narrowly specialized to perform specific tasks like current AI systems.
GPT is not equivalent to AGI, as it is a specific type of machine learning model that is designed to perform natural language processing tasks, rather than being able to perform any intellectual task that a human being can. However, some researchers believe that the development of AGI may require the use of machine learning models like GPT as a building block, as they can be used to train AI systems to understand and generate human-like language."""
It similarly told me it is also not a "form of AGI"
"A high resolution picture of the Insight Mars Rover on mars, with a simple, light weight and foolproof robotic arm brushing sand off its solar panels, in the style of Greg Rutkowski and Alphonse Mucha, 4k, trending on artstation"
I suppose this is kind of a trivial question, but does anyone know if the last message was ACTUALLY the STRING: “My power’s really low. Don’t worry about me though…”, or was it some binary/hex code to represent that, like, "503 ERROR", and the PR department just tweeted its interpretation as “My power’s really low. Don’t worry about me though…”?
It raises more questions. Was this logging message decided by committee or a PM? Was it a dev easter egg? Do they have a writer?
Also, what conditions would trigger this "final" message?
Being a lesser engineer, my stuff just crashes unceremoniously and usually I am alerted not by a sweet note from my prod servers "Hey, looks like prod's going down, don't worry about me, though...", it's usually concerned phone call from a manager.
It would have been a data packet containing the battery gauge and some other metrics, it wouldn't make any sense for the lander itself to waste precious bandwidth by spitting out human readable ASCII strings like that.
They sent two flash chips full of names with the lander, they are transmitting whole hi-res pictures and even Apollo missions already had at least 1.6 kbit/s, sorry but those 64 bytes would have fit everywhere.
But yes, that message didn't exist for other reasons.
My guess is that it's PR baked into the software -- at least the receiver software. It was a line written by someone who understood that just an error code is really bad for humans to read. So they humanized it a bit. They had time to plan this, not like they didn't know this was the likely outcome. Good product management to give the robot a voice.
I’m especially curious whether it actually used the apostrophe, but I suppose the lander itself just sends its usual vitals and the first-person tweets are done by an on-world PR department.
We have other vehicles we could actually probably get cross checks from. Plus, that'd require some serious level of knowledge to fake a foreign species computational responses from little more than non-invasive scans of chips.
...Unless they are that good... and everything we've been sent is a cleverly constructed ruse.
It's clear, there is only one option. Who's up for an expedition?
I'm confused on why the end state for all these rovers is to loose power because of dust on the solar cells. They did such a good job engineering these things to survive the trip and the conditions in general, but they can't give them "windshield wipers for dust"? Seems like with that minor upgrade they could have much longer lifespan.
Windshield wipers add weight and complexity but more importantly add to the budget.
These things are designed only to serve the mission.
This rover was designed to last 1 year and went for 4 so it’s a pretty good result.
Some good discussion here [1] on Astronomy Cast regarding this topic and potential solutions NASA is working on. Such as an electrostatic dust blaster.
They add weight, but also may extend the mission, meaning for science for buck. NASA rovers outlast their no doubt conservatively estimated life expectancy consistently.
Well, you give a mission plan of one year, and design a rover to fit that plan. And because you don't want to fail, you engineer everything to have a tiny failure rate in the first year. That also makes the systems likely to work for many more years, but that's just a side effect. You have only explicitly designed and spent money on that first year. Taking funding from that first year to add a system that only becomes useful in year three is a completely different matter, and likely much harder to greenlight.
Also, something not explicitly stated in this thread is that most of the most important science happens in the first year the rover / lander is there on Mars. You really want that first year to be successful, and anything beyond that is bonus.
Sure, but you also learn from experience. If it turns out dust on panels is usually the limiting factor, and the rover otherwise stay in good shape well beyond expectations, a mitigation for the dust may be an effective solution in reliably operation lifetime and thus mission scope.
I don't buy the "solar panels can be scratched" argument when they're routinely surviving dust storms much more violent than that. I also don't buy the "you need a motor et. al. for retraction" when the one that already exists for extension could likely also be used for retraction - or at least enough of it to give the panels a nice shake.
What I do buy is that panelshaking of this sort uses energy that would be in short supply if the panels are sufficiently blocked to require it. That doesn't seem impossible to solve, either, but I don't blame NASA for not feeling the need to solve it when they already designed and built InSight to exceed its mission parameters.
I believe the answer is that a brushing mechanism would scrape the glass, and some of the dust gets adhered due to static electricity. I've also heard speculation that diminishing returns are a significant concern when it comes to a dust removal mechanism because of the reasons above.
Seems a bit shortsighted to me. Given that if they avoid a catastrophic failure before landing these things seems to consistently last beyond the originally planned mission, they should be building them with mission extensions in mind.
Not putting all your eggs in one basket of course. Shit happens and probes are still lost even today. But a simple device to remove dust such as a vibration function, a small blower fan or something else seems to be a major value add.
Even if it costs $1 million extra to do, it costs far more to build the rover and send it there so you are still saving money.
You're assuming that there's funding for an extended mission, or that said funding wouldn't be better used on other initiatives, or even within the mission that the opportunity cost is worth it.
At the end of the day the best way to ensure mission success is to put the mission first, not future missions, not "nice to haves", put every dollar you have into making the prescribed mission as perfect as possible. You're suggesting the equivalent of "Navy SEALs sometimes get caught in larger than expected firefights, so each man should lug an extra 1000 rounds of spare ammo into combat just in case". And they could, but that would slow them down and endanger the immediate mission, even if only slightly.
The opportunity cost of that million dollars could be that testing is slightly less extensive and that a minor flaw goes undetected, or other work is rushed because the engineers were busy getting the wipers to work properly. It could also be that there's no interesting science to do in that area even with an extended mission, so the mission extension turns out to be completely worthless.
It's a different mindset than most engineers are used to, because we're used to users having vague desires and needs that even when well defined are somewhat ambiguous, so we plan generic solutions for a bunch of different edge cases and assume things will be used in ways other than what they're intended. And we all like building durable stuff that lasts the test of time. But when you're building a missile you don't care about minor memory leaks, and these probes are essentially science-missiles.
Show me a Mars rover that was still functioning but didn't get a mission extension so was just left to do nothing and decay. I doubt you will. If they are still working they are practically guaranteed a mission extension because the cost of continuing to operate a rover that you have already placed on mars and paid for is marginal relative to the mission. The most expensive part is designing and building the probe and then getting it there.
>At the end of the day the best way to ensure mission success is to put the mission first, not future missions, not "nice to haves", put every dollar you have into making the prescribed mission as perfect as possible. You're suggesting the equivalent of "Navy SEALs sometimes get caught in larger than expected firefights, so each man should lug an extra 1000 rounds of spare ammo into combat just in case". And they could, but that would slow them down and endanger the immediate mission, even if only slightly.
That's a massive exaggeration. I am not advocating for a contingency to every possible failure mode. I am pointing out that we clearly have one very common failure mode that can be solved and likely get us far more utility for little investment.
If you are going to compare it to Navy Seals, what I am suggesting is more akin to "Navy Seals can get shot. That's not good and these are highly trained specialists that don't grow on trees, we should probably give them body armor to give them a chance to survive being shot." And we do give them body armor. Yes it adds weight. Yes it costs more money. But more come home to complete more missions.
Yes a mechanical solution to remove dust from panels adds weight and cost but it can be the difference between an otherwise functional probe dying one day due to low power or dying years later once its electronics fail.
And just because they get that extension doesn't mean they discover anything useful. We don't just chuck stuff at Mars randomly, landing site are chosen for specific reasons to do specific science. Sure it's possible there's something in a navigable vicinity worth checking out, but also just as likely not. And if there is it should be included in the mission as a secondary objective and the probe specced accordingly.
And yes, the most expensive part is designing and building the probe, that includes designing purely custom wipers/vibrators/whatever, hardening them for space so they survive the journey, testing and iterating them in Mars-like and space-like conditions, all on a limited budget that has to build the rest of the probe to the same exacting standards, all for the possibility that there's something outside of the mission scope worth doing. Intuitively wipers and vibrators seem like cheap commodity hardware because we have them everywhere and economies of scale to support them, so why not slap them on? But that doesn't apply to bespoke things like Mars Rovers.
There are constraints your analysis is not taking into account, there's likely also internal NASA constraints that neither of us know about. It's an appeal to authority, but I'm going to assume the engineers at NASA JPL who have decades of experience building/launching/landing Mars rovers have considered the tradeoffs of wipers/dust removal mechanisms for this specific mission.
If you're asking why they don't add them I've provided some speculative reasoning based on my experience in adjacent industries. If you're arguing that they missed an obvious design flaw and you know how to build a better Mars rover, within their constraints, maybe, but given NASA JPL's track record I have my doubts.
>If you're asking why they don't add them I've provided some speculative reasoning based on my experience in adjacent industries.
See, I don't see it that way. You didn't state it as "here are some possible reasons". You formed your argument as "this is why what you are proposing is wrong". Without actually being an authority on it and knowing if that's true.
Neither am I. But we should be able to discuss hypotheticals and come up with ideas as to possible solutions and their drawbacks. I'm sure there are very good reasons why they don't include them. But, having worked in the aerospace industry although nothing to do with NASA or spaceprobes, I find arguments about budget or building just to the mission unsatisfactory. I'm pretty sure there is an engineering challenge that makes it unworkable or unpractical and you and I are just ignorant to it.
There are obvious benefits to the ability to clean solar panels on Mars. And Space probes tend to be more over engineered than people give them credit for. Yes they are built to extreme margins to optimize capability for low weight. But that capability is great. We are talking about the same engineers who replaced the perfectly workable airbag solution for the skycrane which was far more complicated a solution because it promised to land the vehicle softer and give it a better chance of making it to surface unbroken.
So I can only conclude that there is some kind of engineering problem that prevents it. Maybe Mars dust is more like Moon dust that dirt on Earth and its akin to tiny razors? Brushing it off could damage the solar panels.
Insight is NOT a rover. It's unmovable lander. There's so much less to gain post primary mission. And last two rovers outgrown solar panels anyway and are powered by thermoelectric generators powered by radioactive decay.
I once (around 2010) worked with a nasa designed system for electrically clearing solar panels. It was basically a 3-phase arrangement of transparent indium tin oxide electrodes on the surface of the panels. By supplying high voltage AC, both conductive and insulating particles can be removed by various mechanisms. I thought it worked quite well and keep expecting to see it in the wild somewhere. Maybe it's still in the pipeline somewhere.
(1) they were intended to last for three months and (2) dust is extremely static and there is no really good way there to get rid of this static charge, (3) dust is pretty sharp ('abrasive') and will scratch the surface of the cells if removed mechanically.
Regarding (1), almost all of these Mars robots seem to do useful science well beyond the end of the stated mission, I think the OP was suggesting that maybe it’s time we start trying out solutions for much longer duration missions ?
(2) - could it be possible to introduce an oppositely static charged layer on the panel surface to repel dust to stop it settling in the first place ?
> almost all of these Mars robots seem to do useful science well beyond the end of the stated mission
How are we defining "useful science" here? They all do some kind of scientific investigations, but it's hard to say if it's useful or not. If you look at coverage or discussions about the lander (including here), people get very excited about the landings, and somewhat excited about the pictures. The science almost never gets discussed. Even when NASA tries to hype it up, it seems the most important stuff they have is continually telling us they found Mars has some water and used to be wet, and that there's the possibility there once was life on Mars.
People seem enamored with the idea that we're sending things to Mars and doing "something." But there doesn't seem to be a lot of concern about what that "something" actually is.
I'd go as far as saying "useful science" doesn't have much meaning. The misunderstanding comes from the conflation of "science" and "engineering".
The reason engineering exists is to be useful: to create artifacts and technology to make our lives better, easier, etc.
But science only has three uses: to inform engineering; to satisfy our human curiosity; and to beget more science. Any "usefulness" here is of a very narrow scope. I don't mean to say that it's not important, but that's not the same as being useful.
And even whether or not it's important is hard to say. Whether the experiments being done were important or completely unimportant, we'd get the same thing - hyped up results from NASA talking about how these things were a big deal, vague comments from lander fans about how the landers are doing important scientific work. You're not going to get NASA to come out and say, "actually, we can't think of a good reason to send anything to Mars anymore. Maybe in a couple of decades when our technology improves." Similarly, you're not going to get them to say that the shuttle or SLS were misfires. If you look at the stuff NASA releases, these were all enormous successes.
If I try to look at what the Insight lander accomplished, for instance, I find articles claiming that Insight found that the core of the Mars was much larger than previously thought. Let's leave aside whether the exact size of Mars' core is important or not. If I look for estimates of the size of the core prior to Insight, they're all in line with the estimates that came from the Insight data. From what I can see Insight brought the range of estimates closer together, but it seems to be about what people were expecting beforehand.
It is a bit like asking how exactly does the XGB matrix build in stable diffusion create images. We know the end result that is produced, but we can't pick a single number and talk about what it contributes to the overall algorithm. I would even guess that you could replace any single number with another random value within the appropriate range and you wouldn't be able to tell which AI was before and after. The links each item serves is too complex to work out.
In the same way, any single 'act of science' can be hard to measure. They enable some experiments, which allow us to test some hypothesis. In some cases it is simple enough to point out when it is testing hypothesis that end up benefitting humanity, but that's only part of the effect. Many times a hypothesis is either rejected or fails to be rejected and slightly influences a larger theory which in turn is used to create new hypothesis. This creates a circular reference until some time later we end up with a theory that is useful for improving humanity. But which hypothesis were actually pivotal to forming the theory? Which acts of science allowed testing a hypothesis and receiving a clear enough failure that future effort was reallocated to other, eventually more fruitful, areas? Other than trivial cases, the cause and effect becomes such a tangled web we can't be sure.
You even have the publicity side. Where sometimes the effect isn't directly contributing to the theory, but engaging more attention to a field which leads to more children choosing the route of becoming a scientist.
Math has a similar issue. Much of pure mathematics has no known or foreseeable application. Yet, we can look back at what math does have very useful applications and see how many times the math predated the application being found, sometimes by long enough gaps that those who discovered the tools never saw them to be applied.
Someone is making these value judgements. There's a reason why certain projects get funded while others don't.
If someone has no idea what research will yield results, and has no preference for what research gets funded, that's fine. But if all research is the same to them, they should probably let those who view certain research as more important than others to make the decisions about what gets funded.
There are people who are choosing, and there are reasons behind which might end up being better than others, but those are often half science and half politics. Sometimes the end up being done for less than justifiable reasons. One factor is looking at scientists that seem to have 'scienced' well in the past and favoring them over new scientists. This is more conservative in that less money is sent to random ideas that won't go anywhere, but also means that funding is trapped in more classical theories lead to incorrect models and theories sticking around for longer than they should.
Every part needs to last 3 months. If even one part breaks after 2 months the whole thing failed. Each part increases the odds that one will break after 2 months. The only way to work around this is to design each part to last for 5 years, that way the odds are high that all parts survive for the required 3 months. It also means that odds are reasonable the rover will work for much longer than 3 months, and in many cases you can operate in a degraded state for a even longer.
Spirit and Opportunity lasted for much longer (6 and 14 years, respectively), aided by periodic winds that blew dust off the solar panels. It appears that Insight's location doesn't receive many of these compared to others.
They gave Curiosity and Perserverance a plutonium power source to avoid this issue.
My experience with "why don't they just X" for space stuff is that there's almost always a technical paper on it. This looks like a comprehensive review of different approaches to cleaning solar panels on rovers:
I am sure it comes down to economics really, but I do wonder now about a mission in far future, that would clean solar panels of all those older missions to make them work again. For shits and giggles I guess.
This idea gets brought up in every thread about Insight's dust issues - there is not enough air pressure on Mars for the downwash to clean the panels. For Ingenuity specifically the problem is that it is also far too far away - it would take over ten years for the chopper to reach Insight.
Dust is a factor, but so is cold and diminishing solar. My guess is that the dust isnt a problem until late in the season, and by then they hope to have gotten all the data they came for.
IIRC, one of the reasons the MER rovers lasted so much longer is the dust clearance from wind, which was much more than expected. Perhaps Insight counted on more clearing than they got.
I'd just go ask their Project Scientist on Twitter. @MarkPanning
It costs a lot of time and money simply to keep a mission operating, and these are scarce resources that need to be used for every active mission, old or new. Missions are thus planned for very specific lifetimes. On an organizational level, missions that live too long past their due date cause a lot of problems, too.
This isn't cynicism- it's just the reality of trying to absolutely maximize the science return per scarce dollar spent. I personally would love it if ultimate lifespan was a feasible goal for every mission. So would pretty much everyone! But it isn't.
Some kind of passive self-cleaning solar-cell cover might work. You could direct and shape the wind so it blows more strongly over the cell surface to clean it, or since the dust is charged[1] you might use a conductive layer with the same charge. (Although I'm sure engineers have thought long and hard about this already.)
The static charges necessarily come in pairs so the dust is charged both positive and negative, but the surface also gets charged as dust hits it so trying to blow it off does not necessarily work in the long term. Static dust is a real pain in a low water environment.
This was a surprisingly touching movie about the Opportunity rover. Yes, it's sentimental, and yes, the NASA crew do call it "her." And yes, the rover does remind you of Wall-E. Still, it's a good flick to watch with the family.
Couldn't it stay somehow hibernated until it collects enough sunrays to reconnect in the future? I see the dust cover on photos is really thick, but just hypothetically would it be even possible for probe to be dormant for years and then reactivated?
Even doing nothing but collecting energy the probe needs to consume some power to e.g. keep the batteries at not cryogenic temperatures, so if the panels' energy output goes below this minimum the probe can't really shut down itself without damaging its internals
As a programmer my first thought reading this was:
If I was designing a program to send me back a message and it was super critical I received it, I wouldn't put any quotes or non-alphanumerics in the message. Even if my string handling checks out, if the stakes are sufficiently high, I don't trust em!
I always assumed it sent some short, efficient code with the appropriate error correction, packet loss protection and so on and it was only the receiving program that translated to a verbose string. Is that not the case?
If I was designing such a message I'd make sure there is a lot of redundancy in the message so even if I only received part of it I could figure out what it was. Adding quotes and other non-alphanumerics can add more clues that make the message unique enough to identify it even when significant amounts of the data are lost in transmission.
Yep, I worked in the disk drive industry over twenty years ago, and I was surprised to learn that a lot of what we read off the disk is actually wrong! If not for a lot of generous error correction they'd've been pretty unusable.
I thought it was pretty annoying that the communications are put forth here as if the lander is an animate thing engaging in conversation with us.
Perhaps one day we'll achieve something like that. Heck, maybe we'll send up the grandchild of ChatGPT to be the voice of a future exploration probe. But that's not what we have today. These messages were coded by the engineers who built the thing, and any implication of sentiment is bogus.
I know these are inanimate objects and we shouldn’t humanize them. Blame XKCD, I suppose. But I feel a connection to these robots, and I pray that one day we can go to Mars and erect them a place of honor or bring them “home” to a Smithsonian.
They are a testament to the best of our space programs and the men and women who work in them. It’s amazing how well some of these machines overperformed.
These are the last of the "faithful" ones before AI driven ones make these obsolete. I am already feeling nostalgic for these "dependable and hardworking" robots in advance.
I hate this particular strip (not xkcd of course (which is 60% of the time wonderful) but this specific one).
It anthropomorphises the Rover and we have enough sad news from all over the place to also start to worry about that machine (not even an AI). The next one will be Voyager who is all alone in empty space or whatnot. It is enough that I speak to my computer already.
