An Aerospace Inventor Built a New Coil Launcher. That Launches Paper Planes?

YouTuber Tom Stanton is an aerospace engineer who got sidetracked by 3D printing projects — and it shows! In his latest video, he builds a linear motor while explaining its working principles, and does a stellar job of it. A linear motor can be thought of as a regular rotary motor unwrapped and laid flat. But how does it work? To be frank, it works just like any other motor, but linearly.

Well, that wasn’t a very good explanation, so here’s an analogy: You’re a monkey standing on elevated ground, and you want to travel forward, fast. You cannot just jump off, that would only give you vertical velocity. Then you realize there are swinging ropes placed perfectly so that you can let go of the one you’re holding and grab the next one before the rope starts to pull you back again. That way, each rope will add to your horizontal velocity, and you will have spent your potential energy in exchange for kinetic energy. Now, replace the monkey with a payload, ropes with electromagnets, elevation with a capacitor bank, monkey’s sense of inertia with a hall effect sensor, and hands with a MOSFET (metal-oxide-semiconductor field-effect transistor).

Stanton accelerates a permanent magnet using electromagnets; a hall effect sensor detects when the electromagnet begins to draw the permanent magnet back; a microcontroller opens the matching MOSFET to stop the power to the electromagnet; and the entire contraption is fueled by a capacitor bank. If you want to learn more and see all these in action, make sure you watch the video above, and as always, enjoy!