Oh, no argument that it’d be better in terms of quality but I’m wondering how it’d look from a cost perspective. Say we could make a self-driving rover which could handle basic maneuvering, avoiding / recovering from hazards and storms, etc. – at some point there’d be a trade off between having many rovers running for years for less budget than a human crew would need, and depending on the budget climate it might be better to have a cheaper option that doesn’t fail to deliver any scientific results if a big dependency isn’t funded.
If our world-wide herculean efforts towards building a self driving robotic car have yielded mediocre results, I have low expectations for a robotic field geologist built on a NASA budget.
Also note that even with the limitations, the humans surveyed more ground. Remove the limitation by making the rover a mobile habitat and now the humans can have an even more expansive and productive mission.
Ultimately we're going to colonize space, why take 50x the time to gather the science needed for that goal, when worst-case we can spend 50x the budget and just put humans there to incidentally also gather knowledge on how to live in space.
Assuming equivalent spending Robots are a much better option. But, a manned mission is likely to get ~10-100+x what unmanned missions get so it's hard to say.
Also, those rovers did a really wide range of things for their cost. From driving around 40km and taking pictures to analyzing chemistry and even testing for "wobbles" in the planet's rotation that would indicate a liquid core. Sure, they cost ~500 million a pop, but compare that to 100's of billion for a manned mission that might never reach Mars and things don't look so hot.
However we might be willing to drive a lot more agressively if we know we can get a mechanic out to a stuck rover. Similarly, cheaper delivery might make a large number of smaller more disposable vehicles more appealing for many missions, just like what happened to satellites in the last decade.
Holy smokes what a terrible analogy. Most of the cost for the Mars rovers was getting them to Mars. They would have been a whole lot cheaper if 1) We could have delivered them by container ship and 2) We could have had some guy on mars plug them in so we didn't need cells or batteries and 3) that same guy could service them when they break down.
#3 is a big deal. Planetary probes are way, way, way overdesigned compared to what you need on the earth, and all those "ways" cost exponential amounts of money. It probably wouldn't make sense to try to do everything on the job site remotely, but there's really no reason a teleoperated tractor has to cost substantially more than one with a guy in it.
The short answer is: no. You're talking about an entirely different mission profile, at far greater difficulty and at a radically greater cost.
You need an advanced robot, reliable, highly tested, constructed by the best rover engineers on the planet. You need to spend years designing the overall program. You need to deliver the robot safely to the surface of Mars. You need to operate the program at non-trivial cost for an extended period of time to then look for water etc.
I agree, it seems like the marginal cost of making it a longer-lived and more powerful rover are low once you've gone to the trouble of putting 600 kg on the surface of Mars. Worth noting, though, that this mission is also putting a satellite into orbit.
While I don't agree with the anti-mars thesis of the article, I do think the article is hitting on something important: Robotic exploration is underrated.
Curiosity cost something like 2 billion to build and launch, but there's no reason building a car-sized rover has to be that expensive. With economies of scale + better design-for-manufacturing + reusable rockets the total cost would easily drop by several orders of magnitude. Why isn't NASA building factories upon factories that produce robotic probes?
Something to think about, possibly good or bad. If these rovers hadn't had such longevity, would have had other rovers on Mars in the meantime? If so, would they have been more capable? Or have these rovers represented such tremendously cost effective experiments that we're getting what we would have gotten with other rovers, but saved on launch and opportunity costs (awaiting transit to Mars, possible mission failures, etc.)?
The scientific instruments need to be mass-produced, too, of course. A 7-digit number of rovers would be extremly cheap per piece. Shipping would become a problem though.
Way I see it is, if we can land a rover the size of a minivan on a different planet, we should be able to do this without much more effort. Money, perhaps, yes; but, we've already done it.
Hard to do that from orbit though, getting those solid bits up there takes some work. And when you're on the ground if you're relying on auto-navigation your average speed is less than 1km/day so hard to get a wide survey.
Take the current curiosity mission as an exemplar. It is coming up on having been on the ground for 7 years (August '12). A human team, with the same instruments, and a rover could have achieved all of the science results from Curiosity to date, in less than a month. Further they could have repaired instruments that have become non-functional from spares carried with them.
Opportunity and Spirit covered a combined 36 miles or so in 10+ years of operations, also doable in about a month by a human crew.
So we have nearly two decades of robotic exploration that we could do in about 3 months with a group of people and some transport. Plus they could do additional research that the robots can't because they could combine the instruments in ways the robots cannot, or use different processes the robotics cannot implement.
I realize this sounds like a dismissal of the huge accomplishment and contribution to science that the rovers have made. It is not my intent. Those are valuable things, and some science is always better than no science. What I'm trying to point out that putting people there would have 100x the science return for less than 100x the budgetary impact.
What you could do is have dedicated drones which are essentially movable instruments, so you can have co-operation on tasks and say teams of 3 or 4 (one vaporises, the other has the spectrometer. One drills, the other has the reagents and so on)
If you enter this paradigm then you can eliminate costs such as that long arm which you need to position the instrument package. That arm in of itself is an engineering marvel and it requires a lot of careful design to make sure that it doesn't malfunction. (remember you have a not so light weight at the end, the torque due to that is huge and you have a complex assembly consisting linkages to transfer torque and so on...)
The idea of this is to see how simple and redundant you can make things. If for the cost of that arm we could have one small team of rovers wouldn't it be worth it? Wouldn't it jump start exploration?
Infact, NASA wouldn’t use that sort of SOC for anything critical like the rover itself. Ingenuity was always a marginal experiment with a correspondingly high appetite for risk and ability to accept budgetary compromises.
Mars rovers are incredibly complex because we had a reason to spend the money needed to build them. Who is going to pay people to figure out how to build a snow shoveling robot? It does not seem beyond our current level of tech, just beyond any current economic need.
I am not an engineer but I would be curious to know why the proposed Venus Rover I write about here would not be better. https://link.medium.com/6JDHu2Bajgb
Fluidics based computations should give much better performance, miniaturization and reliability.
You may be interested in "Dispelling the myth of robotic efficiency" [1]:
> There is a widely held view in the astronomical community that unmanned robotic space vehicles are, and always will be, more efficient explorers of planetary surfaces than astronauts (e.g. Coates 2001, Clements 2009, Rees 2011). Partly this comes from a common assumption that robotic exploration is cheaper than human exploration (although this isn't necessarily true if like is compared with like) and partly from the expectation that developments in technology will relentlessly increase the capability and reduce the size and cost of robotic missions to the point that human exploration will not be able to compete. I argue below that the experience of human exploration during the Apollo missions, more recent field analogue studies and trends in robotic space exploration all point to exactly the opposite conclusion.
I think it’s a bit more complicated than that - yes, a ton of great science has been done but there is also a considerable amount of time spent working around limitations, too, and some of those lead to less science being done over the life of the mission.
As a simple example, greater autonomy might allow the rovers to do more by avoiding the number of times where they have to wait for the speed of light (20 minute one-way latency plus annual blackouts) & bandwidth delays for someone at JPL to learn about an obstacle, decide what to do, send commands, and see what happens. They’ve spent a lot of time doing that cautiously because the failure mode of some outcomes is losing a rover, but there are other scenarios where the same is true in the other direction so I’m sure they’re keenly working on ways to make it better able to handle safety navigation and various recovery scenarios for things like losing communications, but I’d expect that might come in the form of a system which operates as they have but logs what it would have done so they can compare the human and robotic commands.
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