I’ve been thinking about alternative power-trains lately. I believe I’ve come up with something that is at least partially novel, and that might have applications for nanotechnology (I don’t think it scales up, unfortunately).
The basic idea is a modification of a standard electric motor (linear or rotary – I’ll show examples with use-cases below). The thought I had was whether it was possible to make the “fuel” for the motor directly power it, rather than using electromagnets powered by electricity.
You’re probably at least somewhat familiar with ferrofluids, even if you haven’t heard the name before.
Step one slightly enhances a standard ferrofluid – If we use keyed magnetic particles (i.e. a programmable magnet) with the same pole sticking out on all sides (see 2D diagram below), and apply a small amount of pressure, we can pack a fair bit of potential energy into a tiny container.
If you place two structures like the one above in proximity, they will always push away from each other. By packing them into a confined space under pressure, and then opening a hole, you can achieve a flow of these particles into a pipe. The underlying idea is to create a completely closed circulatory system with magnetic particles running through it.
If the flow of magnetic particles can be directed close to a rotor, motion can be induced, just like in a standard induction motor:
Alternatively, we could build something like a linear induction motor using the same technique:
By now, any engineer reading this will be saying “that’s a horribly inefficient way to build a motor”. Indeed it is, at scale.
Picture an independently operating nano-machine though.
Powering nanites is a difficult engineering problem. You could build a really small chemical battery, which would have tiny power output and a short lifespan. You could try to build something that uses pressurized gas, but there’s only so much pressure you can apply to a tiny object before something gives, and it would be hard to recharge such a system for reuse.
What I have in mind is a circulatory system within a nanite that moves magnetic particles through “veins”. The system only needs a small amount of pressure to keep it flowing, which could be supplied by peristalsis, or a tiny electric pump. When needed to move a motor or actuator, the magnetic fluid would be run through the appropriate piping, and motion would be achieved. The entirety would be an efficient, closed system that could operate for a relatively lengthy time-frame.