Shooting a bullet in mid air requires a special type of detector to ‘catch’ the bullet in mid air. Usually, a special sensor called a ‘gate sensor’ is used. The trick is a gate sensor is that it can calculate the speed of the bullet and ‘nail’ the shot at the right time. Those are not trivial to build.
This is why I was pleasantly surprised when I got this tutorial from Matt Kane who managed to build a bullet catching circuit for under $2.
Matt used a phototransistor along with a red laser to build cheapass bullet detector with the entire cost of the build being under $2: [Read more...]