This is obviously a missile, and I'm not well-versed in weapons tech, but won't this need a camera to actually track and take out a flying object? So far I just see gps and barometric sensing...
Also 3D printing and some electronics, ok fine, but where do you get the rocket propellant? That seems at least as critical as the software and sensing side of things...
Yeah, this current project uses external sensors (a camera array/grid) for guidance.
He's using potassium nitrate/sugar as his rocket fuel.
Watch the video. He makes his own propellant.