Controlling a coilgun from your iPhone? I guess there's an app for that too! University of Arkansas students Chris Farnell and Michael Helms designed and built a Wi-Fi-controlled optically triggered coil gun for their senior design project while studying Electrical Engineering. The students took one year to develop the nifty coilgun.
Coilguns are projectile accelerators that use electromagnets to pull and then push a magnetic projectile, accelerating it to high velocities. Coilguns are either single-stage or multi-stage; a single-stage coilgun uses one electromagnet to propel the projectile, where a multistage uses two or more electromagnets in succession, each increasing the velocity of the projectile rapidly. In this case, the students built a four-stage coilgun.
The overall concept of their gun is simple enough. It's controlled using an Apple iDevice--an iPhone, iPad, or iPod Touch. The iDevice connects to the coilgun using Wi-Fi and a Wi-Fi hub. The coilgun can turn or move up and down on a turret and fires using the iDevice interface. It also has a camera on the end so that you can see where it's pointing on a laptop. I don't know about you, but I see these students working for the Department of Defense some day.