ETB duty cycle jitter #4833

firmware/controllers/actuators/electronic_throttle.cpp

@@ -208,6 +208,8 @@ bool EtbController::init(etb_function_e function, DcMotor *motor, pid_s *pidPara
 	// Ignore 3% position error before complaining
 	m_errorAccumulator.init(3.0f, etbPeriodSeconds);
 
+	m_dutyIntegrator.init(engineConfiguration->etbDutyThreshold, etbPeriodSeconds);
+
 	reset();
 
 	return true;
@@ -511,7 +513,11 @@ expected<percent_t> EtbController::getClosedLoop(percent_t target, percent_t obs
 		}
 
 		// Normal case - use PID to compute closed loop part
-		return m_pid.getOutput(target, observation, etbPeriodSeconds);
+        float output = m_pid.getOutput(target, observation, etbPeriodSeconds);
+        m_dutyErrorAccumulator.accumulate(prevOutput - output);
+		prevOutput = output;
+		etbDutyRateOfChange =
+		return output;
 	}
 }
 

firmware/controllers/actuators/electronic_throttle.txt

@@ -12,5 +12,6 @@ float luaAdjustment;"ETB: luaAdjustment"
     float etbCurrentAdjustedTarget;;"%", 1, 0, -10000, 10000, 3
 
 	bit etbRevLimitActive
+	float etbDutyRateOfChange
 
 end_struct

firmware/controllers/actuators/electronic_throttle_impl.h

@@ -86,6 +86,9 @@ private:
 	// todo: rename to m_targetErrorAccumulator
 	ErrorAccumulator m_errorAccumulator;
 
+	ErrorAccumulator m_dutyIntegrator;
+	float prevOutput;
+
 	// Pedal -> target map
 	const ValueProvider3D* m_pedalMap = nullptr;
 

firmware/tunerstudio/rusefi.input

@@ -1336,6 +1336,7 @@ gaugeCategory = Throttle Body (incl. ETB)
 	etbTargetGauge	= etbTarget,	@@GAUGE_NAME_ETB_TARGET@@, "%",	0,	100,	0,	0,	100,	100,	1,	1
 	etbErrorGauge		= etb1Error,	@@GAUGE_NAME_ETB_ERROR@@,  "%",	-20,  20,	-10,	-5,	5,	10,  2, 0
 	etbDutyCycleGauge  = etb1DutyCycle, @@GAUGE_NAME_ETB_DUTY@@,					"%",	-100, 100,	-75,	-50,	50,	75,  0, 0
+	etbDutyRateOfChangeGauge  = etbDutyRateOfChange, "ETB duty ROC",					"",	-100, 100,	-75,	-50,	50,	75,  0, 3
 
 gaugeCategory = Sensors - Raw
 	rawTps1PrimaryGauge  = rawTps1Primary, "Raw TPS 1 Primary", "V", 0, 5, 0, 0, 5, 5, 3, 0

firmware/util/math/error_accumulator.cpp

@@ -2,6 +2,8 @@
 
 #include "error_accumulator.h"
 
+// todo: shall we rename to StatsIntegrator or SomethingIntegrator assuming we see not "Error Accumulator" usages?
+// todo: ValueIntegrator maybe?
 float ErrorAccumulator::accumulate(float error) {
 	// We only care about the absolute value of the error
 	error = absF(error);