I think it would be a very useful addition to add "until battery voltage = xxx V" to the loiter parameters in flight planning. That would - naturally - require a voltage sensor but it would be quite useful for autonomous flights. Especially, if there were the possibility to OR it with another parameter, e.g. loiter 30 minutes OR until battery voltage <= 10V.
Additionally, it might be useful to have something like a jump condition based on battery voltage, e.g. "if during this mission battery voltage drops below xx V, break off and RTL/land".
That all still wouldn't be without risk, but if the math while planning the mission is done carefully and reserves are reserved, it would add a nice piece of safety to autonomous missions.
I like it :)
Those who like to count discharge by integrating current should also be able to have it their way, it. "until xxx mAh remain".
However I don't think the MAVLink waypoint types have any provision for it.
Another thing, wouldnt it be possible to take for example, current, altitude, wind direction etc. and calculate an auto super efficient throttle rate? Like "Auto_Throttle" aka Cruise mode? WP distance could use the parameter "Auto_throttle" = 1 to save battery?
Of course you can find out this by yourself, but it is not always efficient with human control and it is always different when you swap batteries, fpv gear, cameras etc.
Im kinda new to this so bear with me if this is already a feature!