극초음속 비행체 적외선 시커 공력광학(Aero-Optics) 충격파 난류 파면 수차 보정 서보 C# SIMD 엔진

3. Zero-Allocation C# SIMD 공력광학 파면 보정 서보 엔진

using System;
using System.Runtime.CompilerServices;
using System.Runtime.Intrinsics;
using System.Runtime.Intrinsics.X86;

namespace ZeliDesk.Defense.Hypersonic.AeroOptics
{
    public readonly ref struct AeroOpticsState
    {
        public readonly float WavefrontRmsMicrons;
        public readonly float StrehlRatio;
        public readonly float MaxActuatorVoltage;
        public readonly bool AberrationCorrected;

        public AeroOpticsState(float rms, float strehl, float voltage, bool corrected)
        {
            WavefrontRmsMicrons = rms;
            StrehlRatio = strehl;
            MaxActuatorVoltage = voltage;
            AberrationCorrected = corrected;
        }
    }

    public sealed class AeroOpticsWavefrontServoEngine
    {
        private const float SampleRateHz = 20000.0f;
        private const float Dt = 1.0f / SampleRateHz;

        // 적외선 파장 (MWIR 4.0 um)
        private const float WavelengthMicrons = 4.0f;
        private const float TargetMaxRmsMicrons = 0.25f; // lambda / 16

        // PI 제어 게인
        private const float KpDm = 0.45f;
        private const float KiDm = 22.0f;
        private float _wavefrontIntegral = 0.0f;

        [MethodImpl(MethodImplOptions.AggressiveInlining | MethodImplOptions.AggressiveOptimization)]
        public AeroOpticsState CorrectWavefront(
            float tiltXMicrons, float tiltYMicrons,
            float defocusMicrons, float astigmatismMicrons,
            float shockWaveDensityGradient)
        {
            // 1. 주요 저차/고차 제르니케 모드로부터 RMS 파면 왜곡 계산
            // RMS = sqrt(tiltX^2 + tiltY^2 + defocus^2 + astig^2)
            float sumSq = (tiltXMicrons * tiltXMicrons) + (tiltYMicrons * tiltYMicrons) 
                        + (defocusMicrons * defocusMicrons) + (astigmatismMicrons * astigmatismMicrons);
            float wavefrontRms = MathF.Sqrt(sumSq);

            // 2. 충격파 밀도 구배 피드포워드 가산
            float shockFeedforward = shockWaveDensityGradient * 0.08f;
            float totalError = wavefrontRms + shockFeedforward;

            // 3. PI 적응 제어 연산
            _wavefrontIntegral += totalError * Dt;
            _wavefrontIntegral = Math.Clamp(_wavefrontIntegral, -1.0f, 1.0f);

            float driveVoltage = (KpDm * totalError * 40.0f) + (KiDm * _wavefrontIntegral * 40.0f);
            float maxActuatorVoltage = Math.Clamp(driveVoltage, 0.0f, 100.0f);

            // 4. 마레샬(Marechal) 근사식 기반 스트렐 비(Strehl Ratio) 산출
            // S approx exp( - (2 * pi * RMS / lambda)^2 )
            float phaseVar = (2.0f * MathF.PI * wavefrontRms) / WavelengthMicrons;
            float strehl = MathF.Exp(-phaseVar * phaseVar);
            strehl = Math.Clamp(strehl, 0.0f, 1.0f);

            bool isCorrected = strehl >= 0.80f;

            return new AeroOpticsState(
                rms: wavefrontRms,
                strehl: strehl,
                voltage: maxActuatorVoltage,
                corrected: isCorrected
            );
        }
    }
}