This is a drone project I'm working on with a friend. The goal is to develop a drone that can achieve extended flight times with applications in animal observation in nature reserves and private security. These applications necessitate flight times upwards of 6 hours and the ability to haul a nontrivial camera load. In addition, the drone needs to stay centered over the landing pad and possibly follow (for example, if the landing pad is in the bed of a truck).

Before starting design, I did some back of the envelope calculations to get a rough estimate for the power levels and payloads I could work with. Here are some initial estimates assuming a cable voltage of ~120VAC.

Estimates

assumption: max payload is about twice max takeoff payload -> 2kg

assumption: battery is 25C

assumption: quad draws 15A continuous

assumption: quad draws 30A peak

assumption: we want to drop no more than 10V over 200ft at continuous current (continuous tether current and cont. quad current are not the same)

step-down converter
populated pcb