I'm trying to be dramatic when writing my book. It involves terminator-like robots that have a flexible outer clear skin that holds its shape yet is moveable, the space in between is filled with goop that resembles skin and has unique textures of how skin looks so it looks realistic and not a bland single color. Edit: the outer layer of goop sticks to the outer skin making it look solid, while the goop replicates its squishiness.

My question is how good at realistic looking would these robots be with the description above. And if one were punctured what it might be like to see a person drain from the head down?

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    $\begingroup$ "Goop" and "realistic looking skin" don't really seem to go together in my head. $\endgroup$
    – Cort Ammon
    Jan 18 '17 at 21:14
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    $\begingroup$ So, it's just a bag of goop, or it's a bag of goop shaped like a human? $\endgroup$
    – Imperator
    Jan 18 '17 at 21:39
  • $\begingroup$ Yeah, this needs more clarity. Maybe you haven't fully realized your idea yet or many it's just awkward phrasing but I just don't understand the whole concept of goop layers. $\endgroup$
    – AngelPray
    Jan 18 '17 at 21:51
  • $\begingroup$ See sackers. $\endgroup$
    – JDługosz
    Jan 19 '17 at 1:26

This is workable, but not ideal

Fluids and gels may produce "softness" but they have a couple properties that will cause you problems.

  • Viscosity, or "thickness" must be perfect. If you use a water-like substance (low viscosity) the fluid will slosh around, creating an odd, unrealistic effect - like the bots are water balloons, or got Botox basically everywhere. Too much viscosity, however, and the flesh will not reshape itself - like a balloon full of flour or honey.
    • As temperature changes, so will viscosity (with most fluids / gels) so a liquid material really isn't ideal: bots in the arctic won't move enough, and bots in the jungle will slosh around a lot. Few fluids can both have the right viscosity and maintain it at Earth temperatures.
  • Displaced fluid (from touching stuff) must be put back... somehow. Pumps everywhere aren't ideal, so your best bet is high pressure. However, high pressures mean a single pinprick could leave your bots spurting out liquid. Not ideal.
  • Gravity is your enemy. Fluid will try to build up toward the feet, and you must either pump it back up, or contain it in very small spaces (at which point you've basically made cells, which kind of defeats the purpose of a liquid layer).
  • Skin has fine detail which a fluid cannot reproduce. Look at your hand: you'll see veins, other layers of tissue, and wrinkles. Bots may look fake without extreme attention to detail - it's hard to put veins into a fluid and hold them there, or preserve wrinkles with a watery substance sloshing around.
  • Blood is red, skin is not. You don't want your bots to be revealed when they accidentally poke themselves with a pencil, and gush ... beige? You may want to consider replicating the process that turns blood red - oxidization - by having iron-rich fluid.

Instead, try...

Latex, or some other polymer. It's closer in appearance to human tissue, we can already make it in abundance, it has generally the same physics as layers of skin, and other polymers have been used on robots before.

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    $\begingroup$ Maybe add an electrical system (like nerves) which causes the goop to stiffen or relax (like muscles). $\endgroup$
    – Innovine
    Jan 18 '17 at 22:08
  • $\begingroup$ @Innovine That's possible, and could be looked into, but I'm still a big polymer advocate :) for sake of cost $\endgroup$
    – Zxyrra
    Jan 18 '17 at 22:16

Current Shapeshifting Technology

There are a number of shapeshifting technologies capable of doing something like what you're asking about. Here are three that are close, and I'm listing programmable matter first because I think it's the closest fit to what you describe, but claytronics is a close second. Most of these are funded at least in part by the U.S. military's research and development branch DARPA.

Programmable Matter

A revolutionary new technology called programmable matter may allow future warfighters to command their equipment to physically change itself to meet new operational needs or to form spare parts or tools. Researchers are developing techniques to order materials to self-assemble or alter their shape, perform a function and then disassemble themselves. These capabilities offer the possibility for morphing aircraft and ground vehicles, uniforms that can alter themselves to be comfortable in any climate, and “soft” robots that flow like mercury through small openings to enter caves and bunker complexes.

In the future a soldier will have something that looks like a paint can in the back of his vehicle. The can is filled with particles of varying sizes, shapes and capabilities. These individual bits can be small computers, ceramics, biological systems—potentially anything the user wants them to be. The soldier needs a wrench of a specific size. He broadcasts a message to the container, which causes the particles to automatically form the wrench. After the wrench has been used, the soldier realizes that he needs a hammer. He puts the wrench back into the can where it disassembles itself back into its components and re-forms into a hammer.


Claytronics is a form of programmable matter. Imagine a bracelet or watch that changes into something else when you take it off. Perhaps it becomes a cell phone, or laptop computer. Although this scenario may seem like science fiction, this and much more will soon become reality with a ground-breaking new technology known as claytronics.

Scientists at Carnegie Mellon University and Intel Research Labs Pittsburgh are just a few years away from bringing to life a futuristic simulation system that can morph nearly any object imagined into another object with different size, shape, color and function.

The building units that make this amazing system possible include tiny micro robots called claytronic atoms, or ‘catoms’, which interact with each other. They behave like atoms in the sense that they become the basic building blocks of the objects they are programmed to form. Here is a demo video.

Each component becomes part of a computerized network of objects and identifies itself based on function; for example, a catom might see itself as part of a human body. On command, millions, or even billions of catoms working together would fall in place to create, in this case, a replicate of a live person.

With claytronics, matter can be transformed into any shape for any purpose. Furniture could change shape; blank walls could grow doors or windows. Catoms could form into people that we would find difficult to discern from the real person. They would appear as an actual physical being, not a hologram.


SquishBot is a DARPA program to develop a new class of soft, shape-changing robot. The goal is to design systems that can transform themselves from hard to soft and from soft to hard, upon command. Another goal is to create systems that change their critical dimensions by large amounts, as much as 10x. Such robots will be like soft animals that can squeeze themselves through small openings and into tight places.


You could use jets of said liquid to create the texture you need, but then you need a way to make those jets. You could have this fluid be magnetic and have magnets control it. You could also have a fluid that reacts to basic electrical signals.


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