The purpose of this question is to know whether or not organic tissue can be used to power and android. Compared to a nuclear cell or an ordinary battery this doesn't seem efficient, it needs food, water, oxygen, the right temperature etc... But the reason for this would be to create an infiltration unit that can blend in with other humans. The android is supposed to stay undercover for an extended period of time, monitoring human activity while avoiding suspicion. In other words it cannot recharge while on a mission so it needs to eat and drink like a normal person.

The technological level is space-age but for convenience the android may not need to be entirely mechanical, it could be just a mechanical brain attached to a human body or just and endoskeleton (very terminator like) with human flesh covering it. The main problem I am facing is how to get enough energy through either bioelectricity or some chemical method to power the mechanical system. More information on what the mechanical system would need to be like for this to function would also be appreciated.

Why not use a human spy or a small spy bot? Simply to not take the fun away from me, that's all. Why settle on making it simple when it can be overly elaborate?

  • 1
    $\begingroup$ Your question is equivalent to "does magic exist" or "is there a life force". It's very, very simple: what can be done with machines can, in theory, also be done with what you call a biological system. Take TNT, a potent explosive. It's pretty similar to a lot of stuff your body produces. There is a lot of what high school teachers call chemical energy in there. While we can't do it right now, there is no known theoretical limit $\endgroup$ – Raditz_35 Jan 18 '20 at 11:04
  • 2
    $\begingroup$ "Your question is equivalent to "does magic exist" or "is there a life force"." Please refrain from calling it that. I am basing this question on the concept of microchips that use bioelectricity, this is not some kind of magic or life force nonsense. . Here's an example: greenoptimistic.com/biologically-powered-microchip $\endgroup$ – user71341 Jan 18 '20 at 13:19
  • 1
    $\begingroup$ You didn't understand my comment. If there isn't anything magic in this world, nothing special about life, then this answer is trivially yes. If you believe in such things, then maybe there is an argument that you can't combine both. As always, if you know very little about a subject, not enough to understand that this is a no brainer, in this case chemistry, don't go into detail. Just say it works. Go for it, there is no problem here $\endgroup$ – Raditz_35 Jan 18 '20 at 13:27
  • 2
    $\begingroup$ Unless you tell us how much electric power is required we can't answer; 1 W is trivial, 10 W is fine-ish, 100 W is sort-of imaginable, 1000 W is out of the question (because a human's cooling system cannot cope with 2000 W of waste heat). For example, a for a normal human at rest the heart outputs about 2 W of mechanical power and dissipates about 4 W of waste heat; this goes up to about 8 W of mechanical power output with about 16 W of waste heat when the human is doing a great sustained effort, or 10 W mechanical power output and 20 W of waste heat when the human is doing the maximum effort. $\endgroup$ – AlexP Jan 18 '20 at 19:30
  • 2
    $\begingroup$ @Raditz_35 Saying "if the world has no magic, living tissue can power machines" doesn't feel like a relevant insight into the OP's question. Imo magic has no part of it; asking if living tissue provides enough energy for electronics is a valid, science-based question. $\endgroup$ – Zxyrra Jan 19 '20 at 0:04

Can a biological system be used to power an android?

"it needs to eat and drink like a normal person" // "The technological level is space-age"

Yes, this can be done

And it doesn't need to be 'space age tech' either.

I can see ways of doing this with existing technology.

In fact by now I think it's probably already been done in a crude way with existing technology : Let me introduce you to Slugbot [LinkOne LinkTwo LinkThree LinkFour LinkFive].

A simple internal fermentation (with the assistance of yeast of course) & distillery system can convert food into ethanol which can then be burned to produce electricity through a small electric generator.

Solid residue can be compacted to squeeze out any excess water (no doubt heat assisted by being placed near the ethanol burning system) & the resulting briquettes themselves burned as fuel to drive a small internal steam turbine for more electricity if desired, though that may not leave you with very convincing 'stools' (little briquettes or pellets of compacted ash) if that's important to you.

Or other bacteria such as those in septic tanks might be used to decompose the food into something with a more authentic human faeces appearance texture & smell while producing methane as a fuel for your internal generators in the same way (if at a micro scale) as Energy from sewage systems.

Excess water can be extracted from the system treated with other bacteria to provide the requisite colour & smell & excreted as 'urine'.

Of course if you're covering your 'android' with real flesh & skin as part of it's disguise you won't need too much treatment of any food taken in to make the faeces & urine look authentic, because you then have to include organs for digesting food & pumping blood (lungs too) anyway to keep the skin alive.

Those of course are for a hard state robot, if you're simply seating a computer in a biological body you can simply use muscle power to generate electricity, with tiny hydro generators in larger blood vessels perhaps or simply lacing bits of the same Piezoelectric material used in some flashing shoes through the body in appropriate places. This small device produced 52 microwatts.

A minimum (if any) handwavium is required for what you want & with (though you don't need it) 'space age tech' thrown in to explain more efficient bio engineered bacteria & minituristion of the systems required you really have nothing to worry about with your idea.

But all that aside your main concern appears to be that it doesn't need to plug itself in thereby spoiling the illusion it's a person & potentially giving itself away & if that's your major concern I can think of at least three non-biological supplementary power sources that could be used.

  1. A flexible subdermal sheet of solar power cells beneath the skin.

Cup your hands over your eyes with the fingers tightly squeezed together now turn your face to the sun, see what I mean, & that's your whole hand with a reasonable thickness of flesh not just a little thin skin, yes the efficiency of power generated will be considerably reduced by a layer of skin but it's not going to be non-existent.

  1. Crystal radio style harvesting of radio waves for electricity, it's what we're beginning to use as a power source for a lot of small wireless devices these days & though not a lot it's still a bit, used to trickle charge batteries while 'sleeping' perhaps.

  2. Nuclear batteries as used in pacemakers.

A desktop PC uses around 0.05 kWh (50,000 milliwatts) & this new prototype battery produces 3,300 milliwatt-hours per gram so a 16 gram one of these should more than suffice if you only want to power an android 'brain' in a human body & as Nickel-63 has a half-life of 100 years it should last more than long enough for your purpose. To power more than just the 'brain' you need a bigger one of course.

Personally I'd probably go for a mix-an-match of elements of several or even all of those ideas.

Sidebar : If you go for one of the human body / android brain options perhaps only replace the higher functions & leave the brainstem in to handle all the autonomous & reflex actions (breathing, heartbeat & flinching if cut or from anything really hot or cold etc).

It may even be plausible to only remove the higher reasoning centres of the brain & retain any learned skill-sets like walking, swimming or playing the piano from your body's 'donor' but I would suggest you ask another question for that if you want to consider it.

  • 2
    $\begingroup$ Slugbot is my new favourite mildly disturbing bit of engineering. $\endgroup$ – Joe Bloggs Jan 19 '20 at 0:34
  • $\begingroup$ @JoeBloggs : How could a flesh eating robot not be ;D $\endgroup$ – Pelinore Jan 19 '20 at 0:35
  • 1
    $\begingroup$ @thescribe-ReinstateMonica: Regular humans eat dead stuff. In fact, they eat mostly dead stuff. When was the last time you ate a living chicken? $\endgroup$ – AlexP Jan 19 '20 at 7:39
  • 1
    $\begingroup$ @Pelinore (a) I missed the "or some chemical method" part. (b) I was not criticizing your other methods, just that one. $\endgroup$ – The Daleks Jan 19 '20 at 12:41

Currently, No. Cells are, by their very nature, designed to not produce much more energy than they need. The extra energy that they do produce is what we call "body heat." If cells did produce excess energy they would broil in their own heat. While there are ways to get around this, we currently do not have the technology to do so.

All that being said, you are talking about the far future. In this case, yes; you're robot can use a Terminator-style human exterior as a disguise. However, it still won't be able to use it as a power source. You know what I was saying about "excess heat?" Well, even though it is theoretically possible to drain this heat away and convert it to electricity, you're robot's infrared heat signature will be drastically higher than a human's. This kind of defeats the purpose of using human flesh as a disguise, so it will still have to plug itself in every so often.

  • $\begingroup$ actually cells waste a tremendous amount of energy generating heat, the cells system for generating heat is very inefficient, basically they just have pumps running in an open system wasting a lot of energy as mechanical motion (that does nothing) instead of heat. If that mechanical energy (ion gradient) could be converted to electricity it could not only generate quite a lot of power, but would also generate more heat making hte process more efficient to boot. $\endgroup$ – John Jan 19 '20 at 14:44
  • $\begingroup$ Yes. Its still not enough energy to power my desktop computer, let alone a hyper-advanced android. $\endgroup$ – The Daleks Jan 21 '20 at 0:18
  • $\begingroup$ To be fair your desktop is very inefficient. it would be enough to run a laptop, even more so if it is solid state one. Most biological systems are very efficient, heat being one of exceptions, so presumably an android will use biological systems when they are more efficient. $\endgroup$ – John Jan 21 '20 at 3:33
  • $\begingroup$ @John I agree that biological systems will be used when necessary; nevertheless, it probably won't be enough to power a 180 pound (at the least, probably heavier) android. That being said, I do wish that this idea could work, as the basic concept reminds me of R. Daneel Olivaw from Isaac Asimov's The Caves of Steel. $\endgroup$ – The Daleks Jan 21 '20 at 15:29

Define ‘android’.

If you mean a machine made to look humanoid then covered in synthetic flesh: there are other answers to cover that.

However: if you mean programmable humanoid robot:

Why not use humans?

Projects already exist to control the motor functions of simple insects. Moths, flies and cockroaches have all been controlled by adding machines to them. Projects also exist to map and stimulate various parts of the human brain for advanced prosthetic work and for neurological condition treatment. Combine these things and there’s no reason you couldn’t replace a human brain with a computer and achieve a reasonable degree of function (future science can solve IO and immunological issues, right?). This solves almost all the energy problems of your android by making them all exactly the same functions as those of the human you’re trying to mimic. Almost all.

See: the human brain is actually a very efficient processor. For the problems it’s good at solving it’s more energy efficient than anything we’ve yet made. Not only that but it’s built to run on the fuel that your body is already giving it. So, unless you can build your own brains out of actual brain tissue (good luck) you also need a hyper efficient computer and a miniaturised energy extraction system. Or a kinetic energy source, a radio link and something that occasionally makes your android shake their head from side to side vigorously. Offload all control to a nearby drone control facility and let your android’s neck muscles do the recharging!

Oh. This also doesn’t give your android any special abilities that a human wouldn’t have. And it’s more likely to get caught. And much more expensive. In fact, why not simply train yourself a set of human beings? With suitable indoctrination techniques you can have a set of perfectly loyal, smart, entirely human looking ‘androids’.

And they’ll come with their own power source ready plumbed in.

  • $\begingroup$ You know, I do believe that this is one of the best answers I have ever seen. +999999! $\endgroup$ – The Daleks Jan 19 '20 at 1:16
  • $\begingroup$ kinetics runs into the problem of mechanical moving parts, why not just use a glucose fuel cell? $\endgroup$ – John Jan 19 '20 at 14:36
  • 1
    $\begingroup$ Praise worthy answer. However -1 for taking the fun away from me. $\endgroup$ – user71341 Jan 19 '20 at 18:21
  • $\begingroup$ @LiveInAmbeR : in fairness (I think?) this answer essentially comes down to install a computer brain in a human body (eventually) which does seem to be one of your allowed options? with some muscle power to electricity (the neck rolling) to run it with, unless I'm reading it wrong? $\endgroup$ – Pelinore Jan 19 '20 at 18:52
  • $\begingroup$ @Pelinore: That’s pretty much right. Or go with the cheaper, more sane option and sink your money into training your own private security forces. $\endgroup$ – Joe Bloggs Jan 19 '20 at 19:11

There probably is a better way to do this, but the most achievable solution would be to have an overdeveloped circulatory system and stick some turbines in there to generate power. maybe you could also stick some rotors in the trachea and the lungs or something. this doesn't seem very efficient although it would be a lot easier to do than any kind of bioelectricity option. it might be more efficient to make a complete human with a robot brain, or a robot which only has a very thin layer of human flesh. both of these take a higher level of technology and the second doesn't quite fit the description you gave since it wouldn't have a biological power source.


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy