rusefi/firmware/controllers/algo/fuel_math.cpp

/**
 * @file	fuel_math.cpp
 * @brief	Fuel amount calculation logic
 *
 *
 * @date May 27, 2013
 * @author Andrey Belomutskiy, (c) 2012-2020
 *
 * This file is part of rusEfi - see http://rusefi.com
 *
 * rusEfi is free software; you can redistribute it and/or modify it under the terms of
 * the GNU General Public License as published by the Free Software Foundation; either
 * version 3 of the License, or (at your option) any later version.
 *
 * rusEfi is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without
 * even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along with this program.
 * If not, see <http://www.gnu.org/licenses/>.
 *
 */

#include "pch.h"

#include "airmass.h"
#include "alphan_airmass.h"
#include "maf_airmass.h"
#include "speed_density_airmass.h"
#include "fuel_math.h"
#include "fuel_computer.h"
#include "injector_model.h"
#include "speed_density.h"
#include "speed_density_base.h"
#include "lua_hooks.h"

extern fuel_Map3D_t veMap;
static mapEstimate_Map3D_t mapEstimationTable;

#if EFI_ENGINE_CONTROL

float getCrankingFuel3(float baseFuel, uint32_t revolutionCounterSinceStart) {

	float baseCrankingFuel;
	if (engineConfiguration->useRunningMathForCranking) {
		baseCrankingFuel = baseFuel;
	} else {
		// parameter is in milligrams, convert to grams
		baseCrankingFuel = engineConfiguration->cranking.baseFuel * 0.001f;
	}

	// Cranking fuel changes over time
	engine->engineState.crankingFuel.durationCoefficient = interpolate2d(revolutionCounterSinceStart, config->crankingCycleBins,
			config->crankingCycleCoef);

	/**
	 * Cranking fuel is different depending on engine coolant temperature
	 * If the sensor is failed, use 20 deg C
	 */
	auto clt = Sensor::get(SensorType::Clt).value_or(20);
	auto e0Mult = interpolate2d(clt, config->crankingFuelBins, config->crankingFuelCoef);

	bool alreadyWarned = false;
	if (e0Mult <= 0.1f) {
		warning(ObdCode::CUSTOM_ERR_ZERO_E0_MULT, "zero e0 multiplier");
		alreadyWarned = true;
	}

	if (engineConfiguration->flexCranking && Sensor::hasSensor(SensorType::FuelEthanolPercent)) {
		auto e85Mult = interpolate2d(clt, config->crankingFuelBins, config->crankingFuelCoefE100);

		if (e85Mult <= 0.1f) {
			warning(ObdCode::CUSTOM_ERR_ZERO_E85_MULT, "zero e85 multiplier");
			alreadyWarned = true;
		}

		// If failed flex sensor, default to 50% E
		auto flex = Sensor::get(SensorType::FuelEthanolPercent).value_or(50);

		engine->engineState.crankingFuel.coolantTemperatureCoefficient =
			interpolateClamped(
				0, e0Mult,
				85, e85Mult,
				flex
			);
	} else {
		engine->engineState.crankingFuel.coolantTemperatureCoefficient = e0Mult;
	}

	auto tps = Sensor::get(SensorType::DriverThrottleIntent);
	engine->engineState.crankingFuel.tpsCoefficient =
		tps.Valid
		? interpolate2d(tps.Value, config->crankingTpsBins, config->crankingTpsCoef)
		: 1; // in case of failed TPS, don't correct.

	floatms_t crankingFuel = baseCrankingFuel
			* engine->engineState.crankingFuel.durationCoefficient
			* engine->engineState.crankingFuel.coolantTemperatureCoefficient
			* engine->engineState.crankingFuel.tpsCoefficient;

	engine->engineState.crankingFuel.fuel = crankingFuel * 1000;

	// don't re-warn for zero fuel when we already warned for a more specific problem
	if (!alreadyWarned && crankingFuel <= 0) {
		warning(ObdCode::CUSTOM_ERR_ZERO_CRANKING_FUEL, "Cranking fuel value %f", crankingFuel);
	}
	return crankingFuel;
}

float getRunningFuel(float baseFuel) {
	ScopePerf perf(PE::GetRunningFuel);

	float iatCorrection = engine->fuelComputer.running.intakeTemperatureCoefficient;
	float cltCorrection = engine->fuelComputer.running.coolantTemperatureCoefficient;
	float postCrankingFuelCorrection = engine->fuelComputer.running.postCrankingFuelCorrection;
	float baroCorrection = engine->engineState.baroCorrection;

	efiAssert(ObdCode::CUSTOM_ERR_ASSERT, !cisnan(iatCorrection), "NaN iatCorrection", 0);
	efiAssert(ObdCode::CUSTOM_ERR_ASSERT, !cisnan(cltCorrection), "NaN cltCorrection", 0);
	efiAssert(ObdCode::CUSTOM_ERR_ASSERT, !cisnan(postCrankingFuelCorrection), "NaN postCrankingFuelCorrection", 0);

	float correction = baroCorrection * iatCorrection * cltCorrection * postCrankingFuelCorrection;

#if EFI_ANTILAG_SYSTEM
	correction *= (1 + engine->antilagController.fuelALSCorrection / 100);
#endif /* EFI_ANTILAG_SYSTEM */

#if EFI_LAUNCH_CONTROL
	correction *= engine->launchController.getFuelCoefficient();
#endif

	correction *= getLimpManager()->getLimitingFuelCorrection();

	float runningFuel = baseFuel * correction;

	efiAssert(ObdCode::CUSTOM_ERR_ASSERT, !cisnan(runningFuel), "NaN runningFuel", 0);

	// Publish output state
	engine->fuelComputer.running.baseFuel = baseFuel * 1000;
	engine->fuelComputer.totalFuelCorrection = correction;
	engine->fuelComputer.running.fuel = runningFuel * 1000;

	return runningFuel;
}

static SpeedDensityAirmass sdAirmass(veMap, mapEstimationTable);
static MafAirmass mafAirmass(veMap);
static AlphaNAirmass alphaNAirmass(veMap);

AirmassModelBase* getAirmassModel(engine_load_mode_e mode) {
	switch (mode) {
		case LM_SPEED_DENSITY: return &sdAirmass;
		case LM_REAL_MAF: return &mafAirmass;
		case LM_ALPHA_N: return &alphaNAirmass;
#if EFI_LUA
		case LM_LUA: return &(getLuaAirmassModel());
#endif
#if EFI_UNIT_TEST
		case LM_MOCK: return engine->mockAirmassModel;
#endif
		default:
			firmwareError(ObdCode::CUSTOM_ERR_ASSERT, "Invalid airmass mode %d", engineConfiguration->fuelAlgorithm);
			return nullptr;
	}
}

float getMaxAirflowAtMap(float map) {
	return sdAirmass.getAirflow(Sensor::getOrZero(SensorType::Rpm), map, false);
}

#if EFI_ENGINE_CONTROL

// Per-cylinder base fuel mass
static float getBaseFuelMass(int rpm) {
	ScopePerf perf(PE::GetBaseFuel);

	// airmass modes - get airmass first, then convert to fuel
	auto model = getAirmassModel(engineConfiguration->fuelAlgorithm);
	efiAssert(ObdCode::CUSTOM_ERR_ASSERT, model != nullptr, "Invalid airmass mode", 0.0f);

	auto airmass = model->getAirmass(rpm, true);

	// Plop some state for others to read
	float normalizedCylinderFilling = 100 * airmass.CylinderAirmass / getStandardAirCharge();
	engine->fuelComputer.sdAirMassInOneCylinder = airmass.CylinderAirmass;
	engine->fuelComputer.normalizedCylinderFilling = normalizedCylinderFilling;
	engine->engineState.fuelingLoad = airmass.EngineLoadPercent;
	engine->engineState.ignitionLoad = engine->fuelComputer.getLoadOverride(airmass.EngineLoadPercent, engineConfiguration->ignOverrideMode);

	auto gramPerCycle = airmass.CylinderAirmass * engineConfiguration->cylindersCount;
	auto gramPerMs = rpm == 0 ? 0 : gramPerCycle / getEngineCycleDuration(rpm);

	// convert g/s -> kg/h
	engine->engineState.airflowEstimate = gramPerMs * 3600000 /* milliseconds per hour */ / 1000 /* grams per kg */;

	float baseFuelMass = engine->fuelComputer.getCycleFuel(airmass.CylinderAirmass, rpm, airmass.EngineLoadPercent);

	engine->engineState.baseFuel = baseFuelMass;

	if (cisnan(baseFuelMass)) {
		// todo: we should not have this here but https://github.com/rusefi/rusefi/issues/1690
		return 0;
	}

	return baseFuelMass;
}

angle_t getInjectionOffset(float rpm, float load) {
	if (cisnan(rpm)) {
		return 0; // error already reported
	}

	if (cisnan(load)) {
		return 0; // error already reported
	}

	angle_t value = interpolate3d(
		config->injectionPhase,
		config->injPhaseLoadBins, load,
		config->injPhaseRpmBins, rpm
	);

	if (cisnan(value)) {
		// we could be here while resetting configuration for example
		// huh? what? when do we have RPM while resetting configuration? is that CI edge case? shall we fix CI?
		warning(ObdCode::CUSTOM_ERR_6569, "phase map not ready");
		return 0;
	}

	angle_t result = value;
	wrapAngle(result, "inj offset#2", ObdCode::CUSTOM_ERR_6553);
	return result;
}

/**
 * Number of injections using each injector per engine cycle
 * @see getNumberOfSparks
 */
int getNumberOfInjections(injection_mode_e mode) {
	switch (mode) {
	case IM_SIMULTANEOUS:
	case IM_SINGLE_POINT:
		return engineConfiguration->cylindersCount;
	case IM_BATCH:
		return 2;
	case IM_SEQUENTIAL:
		return 1;
	default:
		firmwareError(ObdCode::CUSTOM_ERR_INVALID_INJECTION_MODE, "Unexpected injection_mode_e %d", mode);
		return 1;
	}
}

float getInjectionModeDurationMultiplier() {
	injection_mode_e mode = getCurrentInjectionMode();

	switch (mode) {
	case IM_SIMULTANEOUS: {
		auto cylCount = engineConfiguration->cylindersCount;

		if (cylCount == 0) {
			// we can end up here during configuration reset
			return 0;
		}

		return 1.0f / cylCount;
	}
	case IM_SEQUENTIAL:
	case IM_SINGLE_POINT:
		return 1;
	case IM_BATCH:
		return 0.5f;
	default:
		firmwareError(ObdCode::CUSTOM_ERR_INVALID_INJECTION_MODE, "Unexpected injection_mode_e %d", mode);
		return 0;
	}
}

percent_t getInjectorDutyCycle(int rpm) {
	floatms_t totalInjectiorAmountPerCycle = engine->engineState.injectionDuration * getNumberOfInjections(engineConfiguration->injectionMode);
	floatms_t engineCycleDuration = getEngineCycleDuration(rpm);
	return 100 * totalInjectiorAmountPerCycle / engineCycleDuration;
}

percent_t getInjectorDutyCycleStage2(int rpm) {
	floatms_t totalInjectiorAmountPerCycle = engine->engineState.injectionDurationStage2 * getNumberOfInjections(engineConfiguration->injectionMode);
	floatms_t engineCycleDuration = getEngineCycleDuration(rpm);
	return 100 * totalInjectiorAmountPerCycle / engineCycleDuration;
}

static float getCycleFuelMass(bool isCranking, float baseFuelMass) {
	if (isCranking) {
		return getCrankingFuel(baseFuelMass);
	} else {
		return getRunningFuel(baseFuelMass);
	}
}

/**
 * @returns	Mass of each individual fuel injection, in grams
 *     in case of single point injection mode the amount of fuel into all cylinders, otherwise the amount for one cylinder
 */
float getInjectionMass(int rpm) {
	ScopePerf perf(PE::GetInjectionDuration);

	// Always update base fuel - some cranking modes use it
	float baseFuelMass = getBaseFuelMass(rpm);

	bool isCranking = engine->rpmCalculator.isCranking();
	float cycleFuelMass = getCycleFuelMass(isCranking, baseFuelMass);
	efiAssert(ObdCode::CUSTOM_ERR_ASSERT, !cisnan(cycleFuelMass), "NaN cycleFuelMass", 0);

	if (engine->module<DfcoController>()->cutFuel()) {
		// If decel fuel cut, zero out fuel
		cycleFuelMass = 0;
	}

	float durationMultiplier = getInjectionModeDurationMultiplier();
	float injectionFuelMass = cycleFuelMass * durationMultiplier;

	// Prepare injector flow rate & deadtime
	engine->module<InjectorModelPrimary>()->prepare();

	if (engineConfiguration->enableStagedInjection) {
		engine->module<InjectorModelSecondary>()->prepare();
	}

	floatms_t tpsAccelEnrich = engine->tpsAccelEnrichment.getTpsEnrichment();
	efiAssert(ObdCode::CUSTOM_ERR_ASSERT, !cisnan(tpsAccelEnrich), "NaN tpsAccelEnrich", 0);
	engine->engineState.tpsAccelEnrich = tpsAccelEnrich;

	// For legacy reasons, the TPS accel table is in units of milliseconds, so we have to convert BACK to mass
	float tpsAccelPerInjection = durationMultiplier * tpsAccelEnrich;

	float tpsFuelMass = engine->module<InjectorModelPrimary>()->getFuelMassForDuration(tpsAccelPerInjection);

	return injectionFuelMass + tpsFuelMass;
}
#endif

/**
 * @brief	Initialize fuel map data structure
 * @note this method has nothing to do with fuel map VALUES - it's job
 * is to prepare the fuel map data structure for 3d interpolation
 */
void initFuelMap() {
	mapEstimationTable.initTable(config->mapEstimateTable, config->mapEstimateRpmBins, config->mapEstimateTpsBins);
}

/**
 * @brief Engine warm-up fuel correction.
 */
float getCltFuelCorrection() {
	const auto clt = Sensor::get(SensorType::Clt);

	if (!clt)
		return 1; // this error should be already reported somewhere else, let's just handle it

	return interpolate2d(clt.Value, config->cltFuelCorrBins, config->cltFuelCorr);
}

angle_t getCltTimingCorrection() {
	const auto clt = Sensor::get(SensorType::Clt);

	if (!clt)
		return 0; // this error should be already reported somewhere else, let's just handle it

	return interpolate2d(clt.Value, config->cltTimingBins, config->cltTimingExtra);
}

float getIatFuelCorrection() {
	const auto iat = Sensor::get(SensorType::Iat);

	if (!iat)
		return 1; // this error should be already reported somewhere else, let's just handle it

	return interpolate2d(iat.Value, config->iatFuelCorrBins, config->iatFuelCorr);
}

float getBaroCorrection() {
	if (Sensor::hasSensor(SensorType::BarometricPressure)) {
		// Default to 1atm if failed
		float pressure = Sensor::get(SensorType::BarometricPressure).value_or(101.325f);

		float correction = interpolate3d(
			config->baroCorrTable,
			config->baroCorrPressureBins, pressure,
			config->baroCorrRpmBins, Sensor::getOrZero(SensorType::Rpm)
		);

		if (cisnan(correction) || correction < 0.01) {
			warning(ObdCode::OBD_Barometric_Press_Circ_Range_Perf, "Invalid baro correction %f", correction);
			return 1;
		}

		return correction;
	} else {
		return 1;
	}
}

percent_t getFuelALSCorrection(int rpm) {
#if EFI_ANTILAG_SYSTEM
		if (engine->antilagController.isAntilagCondition) {
			float throttleIntent = Sensor::getOrZero(SensorType::DriverThrottleIntent);
			auto AlsFuelAdd = interpolate3d(
			config->ALSFuelAdjustment,
			config->alsFuelAdjustmentLoadBins, throttleIntent,
			config->alsFuelAdjustmentrpmBins, rpm
		);
		return AlsFuelAdd;
	} else
#endif /* EFI_ANTILAG_SYSTEM */
	{
		return 0;
	}
}

#if EFI_ENGINE_CONTROL
/**
 * @return Duration of fuel injection while craning
 */
float getCrankingFuel(float baseFuel) {
	return getCrankingFuel3(baseFuel, engine->rpmCalculator.getRevolutionCounterSinceStart());
}

/**
 * Standard cylinder air charge - 100% VE at standard temperature, grams per cylinder
 *
 * Should we bother caching 'getStandardAirCharge' result or can we afford to run the math every time we calculate fuel?
 */
float getStandardAirCharge() {
	float totalDisplacement = engineConfiguration->displacement;
	float cylDisplacement = totalDisplacement / engineConfiguration->cylindersCount;

	// Calculation of 100% VE air mass in g/cyl - 1 cylinder filling at 1.204/L
	// 101.325kpa, 20C
	return idealGasLaw(cylDisplacement, 101.325f, 273.15f + 20.0f);
}

float getCylinderFuelTrim(size_t cylinderNumber, int rpm, float fuelLoad) {
	auto trimPercent = interpolate3d(
		config->fuelTrims[cylinderNumber].table,
		config->fuelTrimLoadBins, fuelLoad,
		config->fuelTrimRpmBins, rpm
	);

	// Convert from percent +- to multiplier
	// 5% -> 1.05
	return (100 + trimPercent) / 100;
}

static Hysteresis stage2Hysteresis;

float getStage2InjectionFraction(int rpm, float load) {
	if (!engineConfiguration->enableStagedInjection) {
		return 0;
	}

	float frac = 0.01f * interpolate3d(
		config->injectorStagingTable,
		config->injectorStagingLoadBins, load,
		config->injectorStagingRpmBins, rpm
	);

	// don't allow very small fraction, with some hysteresis
	if (!stage2Hysteresis.test(frac, 0.1, 0.03)) {
		return 0;
	}

	// Clamp to 90%
	if (frac > 0.9) {
		frac = 0.9;
	}

	return frac;
}

#endif
#endif