Governor¶
The Governor shapes motor throttle response, from holding a fixed idle output through to actively governing motor/rotor RPM, rather than commanding a raw linear throttle-to-motor-output mapping. This is distinct from PID tuning -- it governs how throttle input translates to commanded motor output, independent of attitude stabilization.
It's configured from the Governor section of the Motors tab. Setting a mode other than Off and assigning the GOVERNOR switch on the Auxiliary tab turns that switch into a hard motor interlock, not just something that shapes the bottom of the throttle curve:
- Switch off -- the motor is forced to 0% output. The throttle stick has no authority at all, at any position, until the switch is engaged. This is deliberate: it lets you arm and handle the model on the ground without the motor spinning, the same purpose an idle-up switch serves on a heli or helicopter-style transmitter setup.
- Switch on -- idle hold or RPM governing activates as described below, and above the handover throttle (or across the whole stick in RPM Range mode) the stick drives the motor normally.
If a mode other than Off is selected but no switch is assigned to GOVERNOR, the interlock does not apply and the motor behaves as if the governor were Off -- throttle passes straight through at all times. Assign the switch if you want the mode you've configured to actually take effect.
Modes¶
| Mode | Behavior |
|---|---|
| Off | Disables the governor entirely; throttle passes straight through. |
| RPM Idle/Max | Holds a target idle RPM below the handover throttle using RPM feedback, starting from the configured Idle Throttle Floor so the ESC is not commanded to zero during a rapid throttle chop. Above handover, the optional max-RPM limit can prevent overspeed. |
| Throttle Idle | Holds a fixed throttle percentage at idle; needs no RPM source, but won't correct for load or battery sag. |
| RPM Range | Maps the throttle stick across a Min RPM (0%) to Max RPM (100%) range, governing speed through the whole flight rather than just at idle. |
RPM Idle/Max and RPM Range modes require an RPM source: bidirectional DShot telemetry, ESC telemetry, or a frequency sensor.
Tuning¶
RPM Idle/Max uses Idle Throttle Floor as the minimum powered idle output while the governor is active below handover. The RPM controller then adds P/I correction above that floor to reach the configured Idle RPM. This keeps the motor spinning instead of letting an RPM overshoot drive the command to 0% throttle, which can make the ESC struggle to spool back up.
Set Idle Throttle Floor high enough that the motor keeps turning reliably after a quick throttle chop, but not so high that the aircraft idles faster than you want. If the floor alone produces more RPM than the configured Idle RPM, RPM Idle/Max will not pull below the floor; lower the floor or raise the Idle RPM target. Throttle Ceiling remains the hard maximum output the governor may command, and also caps the effective idle floor.
RPM-governing modes hold their target using a filtered P/I loop: P gain corrects RPM error but always settles a little below target, and I gain closes that remaining gap. Handover Throttle sets the stick position below which RPM Idle/Max or Throttle Idle takes over (not used in RPM Range mode, which spans the whole stick).