Goal
Modify a toy helicopter into a very cheap drone that can be taken out of a pocket, thrown into the air, and then used to quickly map a building. Inspired by the elegant user experience of the manhacks of Half-Life 2 and the analogous economics of Chinese toy clones.
How
Some PCB with an ARM SoC and cell phone camera on it, machine learning, SLAM - I'm not really sure yet. It would be cool to use one of (the new <3 cm^3 laser pico projectors](http://www.st.com/web/catalog/mmc/FM132/SC1600/PF253322) STMicro is getting to market in order to do depth scanning, but the part isn't available to non-incorporated low-lifes like myself yet. Instead I might first try just a regular cell phone camera with a fish-eye lens saving video to flash memory. Then when the drones return to home base they can dump the video and image correlation algorithms on a laptop or phone can extract the 3D scenery. Another fun possibility would be to build some tiny galvos and add a laser. Then the camera on the drone could measure the offset of the laser dot to get noisy depth data. After collecting a bunch of that it would be dumped on home base for correlation and cleaning.
Good luck! The hardware actually looks pretty simple, Im guessing the tough part will be working out the flight software. Then the autonomy thing, but at this size and cost you can probably afford some trial and error compared to people with multimillion dollar budgets. Anyway, good luck again!