Morning all,
I installed Arduplane on my old aerobatic biplane.
Since it is a really nervous plane, I need exponential on ailerons, elevator and rudder.
Documentation gives BIG warnings about transmitter settings, saying: “do not touch anything after transmitter calibration”. I also see there are some parameters to set the expo functions for manual mode on arduplane side, but would be more convenient and practical to have on radio side.
After some brainstorming I can’t find any problem in setting the expo function on the radio side as long as I don’t touch the trims. Of course the expo will be active also when flying in FBWA and other modes, but it’s fine…
Am I right? Can I set the expo on radio side without having issues?
Yes, everything is written correctly, do not touch the transmitter. You can use the options from the manual at the link MANUAL Mode — Plane documentation /
the MAN_EXPO_ROLL, MAN_EXPO_PITCH, and MAN_EXPO_RUDDER parameters will apply exponential to the stick inputs, if non-zero, in this mode. This is for users with transmitters which do not provide this function and desire to “soften” stick feel around neutral. ACRO Mode — Plane documentation
the MAN_EXPO_ROLL, MAN_EXPO_PITCH, and MAN_EXPO_RUDDER parameters will apply exponential to the stick inputs, if non-zero, in this mode. This is for users with transmitters which do not provide this function and desire to “soften” stick feel around neutral.
My biplane is also aerobatic with an internal combustion engine. When taking off, I use manual mode, then I check RTL mode; if it happens correctly, I use autonomous waypoint flight.
If you use the transmitter setup in EXPO, this will affect the FBWA mode. For example, in manual mode, I turn on the transmitter DUAL RATE, but then in stabilisation modes I don’t have enough of these costs, the plane responds very slowly, so I return the DUAL RATE to the normal position.
I am confident in the wisdom of the developers. If the parameters MAN_EXPO_ROLL, MAN_EXPO_PITCH, and MAN_EXPO_RUDDER were added, then this decision was justified for optimal control of the aircraft. Thanks to the developers for such a wise decision.
Exponential will increase deadzones as the stick will have to move further out of the middle to reach deadzone end.
If you have small deadzones (RCx_DZ) there shouldn’t be much issue with using Expo and even rates as long as you are aware of the effect that will have on autopilot inputs and controllers’ targets.
IMHO expo and rates stop making sense in FBWA and above as you are setting targets in fairly constrained ranges.
