Well if he can get a copy of the source code used on other flight controllers and memic the circuits and apply his own code then its feasable but the kits and parts for mini quads are getting cheap and building a flight controller sounds tough but look on line for open source projects regarding flight controls and drones there are free sources that might give him a better overall view of how to approach this task…
If your son is more interested in the programming side, you’ll probably want to use either an arduino or a pi like you said, but you will probably have to sink some money into a quadcopter if you want to carry a gopro (around $100 just for capable motors). Racing also is much easier to do with dedicated Electronic Speed Controllers (ESCs) and flight controllers. Seeing as the phantom is expensive and closed source, building is really the only option. When you say use the pi as the server, are you talking about the ground transmitter or the on-board flight controller? If you have a pi on-board rather than an arduino, the size goes up, and the pi consumes more power from my limited knowledge, so a large 450 type quad might be the best option, but that brings the price up as you require stronger motors for the extra size, and larger batteries for the pi. You will, however, be happy to hear that there isn’t as much soldering as you expect. Your son should be confident though, because the heat from the iron can destroy some of the more fragile electronics. Check the package for a maximum temperature.
Overall, youll need around $400 to lift a gopro and pi (just the drone, not including First Person View (FPV) receiver and transmitter to control the drone with. Maybe the best option is to buy a ready-made kit and tinker with the open-source flight controllers before sinking cash into flying a pi.
Regardless, good luck with the project
I’d agree with the suggestion of a 450size quad, although a 550 Hexacopter will still fly if you lose a motor, prop, control of an ESC, more expensive of course (2 extra motors , ESC’s, props).
There are always second hand quads on eBay which sell for less than the component costs so even if your son wants to built from scratch it’s a great source of cheap parts. (I know from experience I sold a fully working Predator 650 for not much more than the motor and controller cost, the buyer told me rather apologetically he was stripping it down for the parts )
Hope this helps
Of course he can do it. Some kids who are younger than him are already doing these things. Just give him more supporting.
There are so much options available to build a drone that can carry a GoPro or decent camera but fill price would be around $200-300.
If that’s your budget talk to Alex @unmannedtech he can suggest suitable kits/bits at this price point
If he know how to solder, then yes, he can!
Soldering is not the most difficult part, I think.