Gear control by flight controller + autonomous recharging

Perhaps you could integrate a “return to home” function in ardupilot (if not already the case) and a “pitstop” function. Both would require the ability of the flight controller to operate the gear (first one just for landing on the gear, second one to land on the gear and take off from the gear with a user-settable wait time in between). The wait time should be settable depending on the time it takes to recharge the plane.

Also, are you actually working on an electric recharge station for RC planes (and other ardu-vehicles ? If not, perhaps worth considering. There seems to be one project involved in this (see https://phys.org/news/2016-10-drones-re-charge-airborne-technology.html ) but really, it doesn’t need to be wireless. An electric conducting pole or something could also be used. The plane can then just taxi to the pole and extend a metal beam to touch the pole and send the power to it’s battery.

There is already a return to home function in ardupilot, it’s called RTL (return to land)
There are already pitsop function, those are called “rally points”

There is no comunity developped hardware for recharging yet. And no software for that.

See here
It says it will “loiter”, so won’t land.
Same with rally points. Only copters will land, not planes.
Also, the pixhawk for instance doesn’t have a channel for the gear either, so ardupilot can’t extract or retract the gear.
Taxiing too can’t be done (can’t be commanded via the route planner, and the recharge function in which to taxi to it for the last 10m or so doesn’t exist).

Sorry, my bad I assumed you wanted a copter.
Here is some info that you need : http://ardupilot.org/plane/docs/automatic-landing.html
The PixHawk has 14 PWM servo outputs. ANY one of this can be configured to control a landing gear on a Copter. http://ardupilot.org/copter/docs/parameters.html?highlight=parameters#servo10-function-servo-output-function just set SERVO_*_FUNCTION to 29 It should not take more than 5 lines of code to implement that in Plane. And you can just copy the code from copter. just search for LandingGear in the copter source code.

EDIT: take a look at: https://github.com/ArduPilot/ardupilot/pull/7893 it does add landing gear support to Plane

Taxi can probably be done using a GroundSteering SERVO_*_FUNCTION. Take a look at that.