d-jsb / CRJ700-family

The Bombardier CRJ700 series for FlightGear Flight Simulator.
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Use the correct constant name for pi-simple-controller #68

Closed ndim closed 4 years ago

ndim commented 7 years ago

The Pitch controller of type pi-simple-controller had two constants defined: Kp=-0.05 and Ti=-0.10.

This made no sense as a pi-simple-controller knows only the two parameters Kp and Ki, not Ti, and thus the controller was actually running as a purely proportional controller with Kp=-0.05 and Ki=0.0.

However, when following an ILS glideslope, the missing integration term lets the aircraft drift below the glideslope.

Keeping the values Kp=-0.05 and Ki=-0.10 (changed from Ti to Ki) make the AP able to follow an ILS glideslope, but it introduces serious pitch oscillations at altitude hold at airspeeds over 220kts.

The values Kp=-0.05 and Ki=-0.001 appear to make the whole thing kind of work for both altitude hold and following a glideslope.

More fine (and probably coarse) tuning needed after the FDM rework.