Foldable QuadCopter (with UDI Parts)

Foldable Quadrocopter

I cannibalized an UDI-818A and used the rotor-arms and the circuitboard for this project. There are some other copters available on the market using nearly the same parts but have different labels/names. Here it is just necessary that the arms have a 4x4 mm profile.

I made a bracket for the arms that is able to engage in different positions. So you can change the behavior of the copter in some ways ... that's fun.
The brackets are very tight to the case so maybe th