Adjust TPA parameters for fixed-wing aircraft

[sensei-hacker]

User description

• Increase fw_tpa_time_constant default from 1500 to 2000ms
• Raise airspeed TPA factor upper limit from 1.5 to 2.0

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PR Type

Enhancement

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Description

• Increase fw_tpa_time_constant default from 1500ms to 2000ms

• Raise airspeed TPA factor upper limit from 1.5 to 2.0

• Adjusts throttle PID attenuation parameters for fixed-wing aircraft

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Diagram Walkthrough

flowchart LR
  A["TPA Parameters"] --> B["fw_tpa_time_constant"]
  A --> C["Airspeed TPA Factor"]
  B --> D["1500ms → 2000ms"]
  C --> E["1.5 → 2.0 upper limit"]

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File Walkthrough

	Relevant files
Enhancement	pid.c Increase airspeed TPA factor upper limit                                  src/main/flight/pid.c Updated calculateFixedWingAirspeedTPAFactor() function Changed airspeed TPA factor upper constraint from 1.5f to 2.0f Allows higher TPA factor values for improved throttle response scaling +1/-1
Configuration changes	settings.yaml Increase TPA time constant default value                                  src/main/fc/settings.yaml Updated fw_tpa_time_constant default value from 1500 to 2000 Increases TPA smoothing and delay time constant for fixed-wing aircraft Reflects slower non-instant speed/throttle response characteristics +1/-1

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[qodo-code-review]

PR Compliance Guide 🔍

All compliance sections have been disabled in the configurations.

[qodo-code-review]

Suggestion: Add a check to ensure tpaFactor is a finite number before the constrainf call to prevent potential propagation of NaN or inf values. [possible issue, importance: 7]

Suggested change

	tpaFactor= constrainf(tpaFactor, 0.3f, 2.0f);
	float factor = tpaFactor;
	if (!isfinite(factor)) {
	factor = 1.0f;
	}
	tpaFactor = constrainf(factor, 0.3f, 2.0f);

[qodo-code-review]

Suggestion: Add a defensive fallback when fixedWingReferenceAirspeed (or the exponent inputs) are invalid/uninitialized to avoid returning extreme/NaN values from powf(). Default to a neutral factor (e.g., 1.0f) when configuration is non-positive or non-finite. [Learned best practice, importance: 6]

New proposed code:

 static float calculateFixedWingAirspeedTPAFactor(void){
     const float airspeed = constrainf(getAirspeedEstimate(), 100.0f, 20000.0f); // cm/s, clamped to 3.6-720 km/h
     const float referenceAirspeed = pidProfile()->fixedWingReferenceAirspeed; // in cm/s
-    float tpaFactor= powf(referenceAirspeed/airspeed, currentControlProfile->throttle.apa_pow/100.0f);
-    tpaFactor= constrainf(tpaFactor, 0.3f, 2.0f);
+    const float exponent = currentControlProfile->throttle.apa_pow / 100.0f;
+
+    if (!(referenceAirspeed > 0.0f) || !isfinite(referenceAirspeed) || !isfinite(exponent)) {
+        return 1.0f;
+    }
+
+    float tpaFactor = powf(referenceAirspeed / airspeed, exponent);
+    tpaFactor = constrainf(tpaFactor, 0.3f, 2.0f);
     return tpaFactor;
 }