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Simplest use of AutoTune:
- use stock PIDs (or known, slow, smooth PIDs that do not have "invisible oscillation") in bank #1
- set up and save FMS (Flight Mode Switch) for
--- FMS#1 Attitude mode manual throttle (Stabilized 1) on bank 1
--- FMS#2 AutoTune mode (like Attitude mode but with shaking) on bank 1
--- FMS#3 Attitude mode manual throttle (Stabilized 1) on bank 3
- after saving, power off and on the FC so it sees AutoTune and enables the AutoTune module
- take off with FMS #1
- switch to FMS #2 and after 2 seconds, it will shake around for 60 seconds
- land after shaking stops
- disarm
- switch to FMS #3
- arm
- carefully take off to test the new PIDs (be ready to instantly drop by using zero throttle if anything strange happens)
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The recommended setup for running AutoTune uses a 3 position FMS (Flight Mode Switch). With this, you can take off and fly Attitude mode with known working PIDs, run AutoTune with known working PIDs and fly Attitude mode with new PIDs, all without using the GCS:
Pos#1 - Attitude mode using bank 1
Pos#2 - AutoTune using bank 1 with SystemIdentSettings.DestinationPidBank set to 3 (that is the default)
Pos#3 - Attitude mode using bank 3 (bank 3 is where the tuned PIDs are written by default)
PID bank 1 should have default PIDs or something that is at least known to fly without oscillations.
PID bank 3 should have default PIDs or something that is at least known to fly without oscillations in case you use it before successfully completing a tune.
This setup can all be done at home, and everything else can be done at the flying field, without using the GCS.
With this FMS setup, you always have Pos#1 to fall back on. Use Pos#1 to recover from any bad situation or to start over and run AutoTune again.
An alternate FMS setup for a 2 position FMS removes the ability to fly with default PIDs once you have run AutoTune:
Pos#1 - Attitude mode using bank 3 (bank 3 is where the tuned PIDs are written by default)
Pos#2 - AutoTune using bank 1 with SystemIdentSettings.DestinationPidBank set to 3 (that is the default)
PID bank 1 should have default PIDs or something that is at least known to fly without oscillations.
PID bank 3 should have default PIDs or something that is at least known to fly without oscillations.
PID bank 3 starts out with the same PIDs as bank 1, but the PIDs will be changed by AutoTune.
It is possible to arm in Pos#1, then switch to Pos#2 and immediately take off before the AutoTune shaking starts (two seconds), if your tuned PIDs don't work and you want to retune.
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