Energy requirements for robot lost at sea

That introduces more problems and adds a risk of implosion. (A reason the robot avoids flying is because if the plane crashes, it could be destroyed. I've been skydiving, I'm aware that chutes [and backup chutes] are quite reliable, it's more about risk mitigation and avoidance.)

Fission is a non-starter, too many issues (energy conversion, safety, horsepower, etc.). Although we'll probably achieve net positive commercial fusion well before 2064, I'm doubtful that we'll have small-form fusion confinement that can fit inside of a 2.0 m x 0.5 m tube, even without accessories (e.g., arms, microdrones, brain, and backup power). Not even the Alcator C-Mod tokamak would fit (the cooling system alone is probably too large).

I've given the novel harder constraints than typical hard sci-fi that precludes ̶u̶n̶o̶b̶t̶a̶i̶n̶i̶u̶m̶ undiscovered materials or hand-wavy advanced technology. If it's not backed by science, I won't use it in the story. Keep in mind, it's also near-future sci-fi.

 

https://www.engineering.com/story/fully-superconducting-motor-prepares-for-testing

Some discussion that might be applicable, starting with about Post Number 10:

Electric Outboard Speed https://www.boatdesign.net/threads/electric-outboard-speed.68283/#post-950811

Plenty of scientists are pursuing higher temperature super conductivity, so my guess is that higher than room temperature superconductivity is at least theoretically possible? Maybe a search will turn something up..

 

I guess my running on the bottom idea was a bit strange - there is no reason for a robot not designed for extreme depth to be capable of sustaining the pressure.

Unless - maybe the robot was designed to lay oceanic cable on the bottom of the sea. But now the robot (actually - "cyborg" - a robot requires remote - usu0ally human - control, and possibly does not need AI) has to find a new path where the magnetic anomalies have not yet been mapped, making compass navigation unreliable. (At the bottom of the sea, star navigation is impractical, unless someone creates compact highly directional neutrino or graviton detectors.)

After all, AIs have (at present) no civil rights. A company might send out a succession of such AI powered cyborgs, most of which "die", until one makes it.

A robot actually designed to swim could be a lot more efficient at it than one which isn't, and could perhaps overcome the denser-than-water problem.

Nuclear fusion is not all that strange. For a time, many people believed that cold fusion - which could have been quite compact - could work. E.g., I knew a couple people (Scott and Talbot Chubb) who developed a theory based on ion band states. They argued that if electrons could occupy band states - which is extremely well accepted and tested theory and practice - maybe ions, like deuterons could too - and Scott of them had done a PHD thesis based on the idea that hydrogen packed into palladium too quickly, which he thought could be best explained by assuming some hydrogen nuclei (protons) entered a band state. Scott initially rejected the theory because the deuterons should have merged into an alpha particle (He nucleus) with too much excess energy to be stable - so many would have decayed, producing many neutrons, which Pons and Fleichman claimed not to be present. Talbot pointed out that if the alpha particles themselves entered band states - because Helium was too large to fit in the palladium matrix - there would be no neutrons. (Though other people pointed out there would be a few produced at crystal defect points.) The people who sponsored their work - considered to have a high risk of failure, demanded rapid results, and they were not able to produce them. Talbot, and experimental chemist, did carefully examine the apparatus of someone who claimed to have succeeded to produce cold fusion, but found that the excess heat was caused by a short circuit, not fusion.

Paul Dirac, a name well known to people who study quantum mechanics, came up with another semi-plausible theory for cold fusion. He assume the existence of an as yet undiscovered exchange particle.

There are ways that might conceivably make "hot fusion" work too. It's basically a containment problem - the reactant needs to stay more or less confined for the reaction to build up. Some partial success has been obtained using laser confinement. Assume a greatly improved generation of high powered lasers, or something along those lines, and maybe (I'm not an expert) you might just make it work. The radiation from hot fusion is pretty high - but there are fusion reactions that might not produce all that much radiation. Besides, maybe the robot can take it.

People use fission in nuclear powered submarines and ships all the time. They've had fairly compact space-born nuclear fission reactors too (e.g., the Russians have used them), though the idea of putting nuclear reactors into space, where they could re-enter the atmosphere, break up, and spread contamination, scares a lot of people, and maybe it should. But maybe (I'm not sure) even nuclear waste materials can get fairly hot, and provide steam power - maybe jet steam power underwater, which could make your robot go reasonably fast.

Your cyborg could also be powered by broadcast power, from an aircraft or satellite. Radio waves, or laser, or maser, etc. But that might not merge well with your idea that the cyborg is "lost" at sea.

Most "hard science fiction" does assume science and technology that go beyond current limits. But it is true that many of the best - e.g., Asimov, Heinlein, Clarke - were working scientists or engineers. Michael Crichton had actual medical training. Poul Anderson had a BA in physics. Larry Niven used a lot of real physics, and did some graduate level mathematics. And, if I remember this right even Frank Herbert's father did agricultural work in arid climates, and might possibly have worked on the 1950's era USDA project to transform the climate of the High Sierras (also cancelled by treaty). Etc. If you don't have a hard science or engineering background, hard SF may be hard to write convincingly. Anything you write is likely to be mercilessly criticized by people with that kind of background. Whereas fantasy usually isn't expected to meet the same kind of scrutiny - though even there, consistency is much appreciated. But perhaps you would find Fantasy easier to get into?

 

After having worked on the novel for over seven years, I'm not inclined to change genre.

Most of this exploration in this thread will emerge primarily as two items in the novel. First, an illustration so that I needn't describe the robot's form. Second, a single sentence that indicates how long it takes the robot to get to shore.

If anyone would like to be an alpha reader and help nit-pick some of the technical issues, or find plot holes, I'd be happy to send a copy.

 

I'm feeling generous today, so here is the truth: installing a prop into a big rim that turns with it doesn't work. The spinning rim becomes a huge drag generating device, and it prevents the prop from working. In other words, it's gonna churn water extremely well, but not much else.

 

I am very glad Rumars has commented because, my intuition say the robot won't move.

Ultimately, what has made most of scifi corny to me is the author stretches reality so far; it becomes nonsensical. I was refreshed you came here asking about reality.

But I am wondering why there is no rendering of the robot, or at least one that makes sense. It would make the book so much better. Can anyone explain how a propeller on top even without a thick nozzle would do anything? Or why the bottom prop is not drawn in the flow or am I the only idiot here not comprehending?

 

The Wheels part may need some modifications depending on what speeds, distances, and type of terrain are to be covered for the land travel part of the story..

 

Though that Goodyear design was designed for an air/car, not water. And as I mentioned in another thread, a wheel/propeller is unlikely to be very efficient at both.

There are other speculative elements in the story. I guess the author assumes successful achievement of an AI with human level intelligence and consciousness, which, AFAIK, is as yet unproven. But that kind of assumption is well within hard SF boundaries.

Other hard SF have included elements which turned out to be impractical. E.g., maybe when Asimov introduced the positronic brain for his "robots" (and other AI computers), positrons were newly discovered particles with many undetermined hypothetical properties. He must have eventually realized that including antimatter in a computational device was impractical and dangerous - but, while he revised some of the elements in his stories to match evolving science, he kept the positronic brain, perhaps because it had been mentioned in so many of his stories.

BTW, when I mentioned cold fusion, I don't actually believe that it has yet been achieved, or that it necessarily will be. It's been too long since Pons and Fleischmann made their announcement. No matter what conspiracy theories you believe, big secrets like that tend to eventually come out, no matter how much effort governments, companies, and/or crime syndicates put into suppressing them. Plus, a lot of people tried to achieve it. But if the Chubbs' theories have any validity, that a periodic charge potential could create an ion band state, and that nuclear reactions can occur within such a band state, I could at least imagine someone creating an engineered material and/or device inside of which it just might work.

It looks like I was wrong to say that the proper term was cyborg rather than robot. There are autonomous "robots", and cyborg implies some other things.

I was just thinking about other types of robots designed to walk on the bottom of the sea - or at least the continental shelf. I could imagine one designed to prospect for material deposits to eventually be mined.

Anyway we should wish the would-be author the best of luck.

(BTW, many hard SF writers have also written fantasy.)

 

Much appreciated. Revised:

I greatly appreciate all the help you all have given.

That is the robot, and it makes sense in the context of the story.

I don't understand this question. Elaborate?

The bottom propeller wasn't drawn rotated into the flow because the model isn't rigged. I'm not a professional 3D artist nor rigger. My plan is to get the broad brushstrokes down and then hire someone to do the modelling and rigging.

Correct, the robotic form contains an A.G.I. Given that human brains exist, I don't think it's outside the realm of science to imagine that we can recreate one, with enough time and effort.

 

So, the robot has left and right wheels.

Then when it enters the water, it turns 90 degrees to one side or lays over. Then the two wheels on say the port side become stabilizers to keep it from sinking and the two wheels on the starboard side become a top and bottom propeller? Have I got this right, finally?

And then only two props for propulsion for n aft?

 

Let me try again: you can not weld the propeller tips to a circular rim and expect it to work. Even the hubless prop has a stator encasing it, functioning like a ducted propeller.
Face it, as cool as props welded into wheels look, it's not realistic.

If you're ok with slow speed simply have a prop emerge from some submerged part of the robot. Doesn't matter if it's a normal folding one, or a cyclorotor (aka. Voith-Schneider). To be more sci-fi, if you decide room temperature superconductors are available, you can try a magnetohydrodynamic drive.
If you want high speed you grow foils, look up electric foiling boards.

 

That's the idea, yes.

More like upper and lower propellers.

There's an amphibious rover using a similar in-wheel propeller concept:



There's no video of it working, so maybe their concept was dead in the water?

There's a paper, Amphibious Wheels with a Passive Slip Mechanism for Transformation, that provides another type of amphibious multimodal wheel. Another paper, On a Bio-inspired Amphibious Robot Capable of Multimodal Motion, takes a different more eel/fish-like approach, though still using an in-wheel propeller design (here's a second version with close-ups). Other papers call out a "propeller-leg" design, such as Design of an Autonomous Amphibious Robot for Surf Zone Operation: Part I Mechanical Design for Multi-Mode Mobility. In Design of a Wheel-Propeller-Leg Integrated Amphibious Robot, the authors include a photo of a wheel-propeller design alongside hydrodynamic torque and thrust comparisons; Figure 8 (c) is the design most similar to my renders.

The SHOALBOT is intriguing. About 4:30 into the (obnoxiously loud) video, the multimodal wheels propel the vehicle through the water.

A completely different tact would be a paddle-wheel with retractable paddles, as in this video. Not sure about its performance on land or under water. Probably not great.

Is that always going to be the case, or does the propeller-leg design overcome that obstacle?

 

I can only open some of your links, but the "propeller-leg" isn't a prop in a rim, it's a prop with winglets, each blade has an individual winglet.

Anyway, as another poster said, most of your readers will have no ideea about propellers, you can do whatever you like. The chances that one of your critics knows something about prop tip clearance are slim, just go ahead and write what you want. I do advice to get your land autonomy adjusted, the chances of readers driving a Tesla or similar are higher.

 

Looking at the image from post #39, it occurs to me that the manipulator arms might be useful. It looks like the arms might be capable of grasping the wheels. If you made the wheels solid (or least mostly solid) and also detachable, then each arm could grab one of the wheels and use it like an oar or paddle. Maybe the wheel has a "handle" structure to specifically enable this mode of travel?

It would not be as efficient as a correctly oriented prop, but there are multiple instances of human-powered rowing vessels of similar size successfully completing ocean crossings, so it should be in the realm of possibility.

 

That's delightfully brilliant. The arms were intentionally designed to grab the wheels for self-repair.

There are a few issues. First, dropping one of the wheels into an abyss would ruin a person's day (though wires would prevent that scenario). The robot's arms have 7 degrees of freedom; the hand, for example, could rotate 360 degrees continuously. That is, swap a hand for a wheel.

Second, the motor for the wheels is a lot more powerful and efficient than that of the arms. Of course, I could move the motors into the hull, and let the arms rotate at the base (connected to the hull). That does have knock-on problems, though.

The wheels will be redone with a slightly modified SHOALBOT style, which should give good performance in all environments.