automatic drone charging - how would you design it?

[NiHaoMike]

Looking at the PCB mounted on the drone, it appears to be a bridge rectifier and buck converter. I clearly see the chain of thought that went into the design: polarity could be either way - use a bridge rectifier to solve that, bridge rectifier drops too much voltage - use a higher voltage and regulate it down. Not bad for an artist with limited EE experience (also keeping in mind it's a proof of concept), but how would an experienced EE design it?

My take is that since weight is basically everything on a drone, the part that mounts on it could be simplified to just a MOSFET + few passives for reverse polarity protection. The base (without the strict weight requirement) would alternate the polarity to the contact grid while monitoring for current draw.

[I wanted a rude username]

Yeah, weight minimisation is paramount. So no induction coil for example.

The drone and pad could negotiate over the pogo pins before the pad applies charging current. Then the drone would always receive the right voltage with the right polarity, minimising weight. If this functionality were integrated into the microcontroller that the drone already has, it would cost a few passives and the pogo pins.

Wu's physical solution is pretty good.