The plane I have uses 2 servos on the elevator. I have a mix program on my radio to slave the 2nd elevator servo (on channel 7) to the elevator controls. That works fine because i like that I can trim each servo from my radio. When I setup the Hkpilot mega 2.7 both elevator servos work in manual flight mode, but only the primary elevator servo works in any of the other flight modes.
I used this article to setup my elevator controls in mission planner: plane.ardupilot.com/wiki/ardupla … ilerons-3/
I setup the 2nd elevator servo on channel 7 input and output. I also programmed rc7_function for elevator with input. Am I missing something?
That’s not quite the way to do it.
You don’t do anything on the RC transmitter for the second elevator.
In the Arduplane setup, you choose an output channel on the APM/Pixhawk and make it use the “elevator” function.
For example, this plane of mine has two elevators, with the second elevator servo on output 7 of the pixhawk. Since the elevator servos are mounted flipped left to right (like aileron servos normally are) the second elevator is inverted.
This will work as expected in all modes, manual and auto. Nothing else is required.
I figured out what the problem was. I had set the min and max for channel 6 instead of channel 7. The min and max for channel 7 were set to the same value, so it went to that one position and never moved unless it was in manual mode.
As far as setting the APM to control channel 7 without radio inputs, I prefer more control over the servos. With radio control of the servo I can do mixes on my radio to switch to elveons or 4x4 when in manual flight mode. Where as, if I didn’t have radio contorl of channel 7, then I would have use a ground station to make any switches like that. Plus it allows me to trim each servo from my radio.
I’ve noticed a lot of people on this forum seam to dislike having multiple radio channels for individual control surfaces.