Version 1.19beta1

Changes to WiFi server and interface code for better network
reliability. FTP and MDNS now working on Duet WiFi.
Changed heater tuning to allow more time for the temperature to rise
when tuning a bed or chamber heater
Toned down the temperaure warning message

1 files changed, 7 insertions, 177 deletions

diff --git a/src/Heating/Pid.cpp b/src/Heating/Pid.cpp
index 9f2e101c..c0be5fb4 100644
--- a/src/Heating/Pid.cpp
+++ b/src/Heating/Pid.cpp
@@ -20,21 +20,16 @@ const uint32_t TempSettleTimeout = 20000;	// how long we allow the initial tempe
 float *PID::tuningTempReadings = nullptr;	// the readings from the heater being tuned
 float PID::tuningStartTemp;					// the temperature when we turned on the heater
 float PID::tuningPwm;						// the PWM to use
-float PID::tuningTargetTemp;					// the maximum temperature we are allowed to reach
+float PID::tuningTargetTemp;				// the maximum temperature we are allowed to reach
 uint32_t PID::tuningBeginTime;				// when we started the tuning process
 uint32_t PID::tuningPhaseStartTime;			// when we started the current tuning phase
 uint32_t PID::tuningReadingInterval;		// how often we are sampling
 size_t PID::tuningReadingsTaken;			// how many samples we have taken
 
-#ifdef NEW_TUNING
 float PID::tuningHeaterOffTemp;				// the temperature when we turned the heater off
 float PID::tuningPeakTemperature;			// the peak temperature reached, averaged over 3 readings (so slightly less than the true peak)
 uint32_t PID::tuningHeatingTime;			// how long we had the heating on for
 uint32_t PID::tuningPeakDelay;				// how many milliseconds the temperature continues to rise after turning the heater off
-#else
-float PID::tuningTimeOfFastestRate;			// how long after turn-on the fastest temperature rise occurred
-float PID::tuningFastestRate;				// the fastest temperature rise
-#endif
 
 // Member functions and constructors
 
@@ -101,7 +96,7 @@ bool PID::SetModel(float gain, float tc, float td, float maxPwm, bool usePid)
 			if (gain > safeGain)
 			{
 				platform.MessageF(GENERIC_MESSAGE,
-						"Warning: Heater %u appears to be over-powered and a fire risk! If left on at full power, its temperature is predicted to reach %uC.\n",
+						"Warning: Heater %u appears to be over-powered. If left on at full power, its temperature is predicted to reach %uC.\n",
 						heater, (unsigned int)gain + 20);
 			}
 		}
@@ -599,7 +594,6 @@ void PID::DoTuningStep()
 	tuningTempReadings[tuningReadingsTaken] = temperature;
 	++tuningReadingsTaken;
 
-#ifdef NEW_TUNING
 	switch(mode)
 	{
 	case HeaterMode::tuning0:
@@ -627,15 +621,17 @@ void PID::DoTuningStep()
 	case HeaterMode::tuning1:
 		// Heating up
 		{
+			const bool isBedOrChamberHeater = (heater == reprap.GetHeat().GetBedHeater() || heater == reprap.GetHeat().GetChamberHeater());
 			const uint32_t heatingTime = millis() - tuningPhaseStartTime;
-			if (heatingTime > (uint32_t)(model.GetDeadTime() * SecondsToMillis) + (30 * 1000) && (temperature - tuningStartTemp) < 3.0)
+			const float extraTimeAllowed = (isBedOrChamberHeater) ? 60.0 : 30.0;
+			if (heatingTime > (uint32_t)((model.GetDeadTime() + extraTimeAllowed) * SecondsToMillis) && (temperature - tuningStartTemp) < 3.0)
 			{
 				platform.Message(GENERIC_MESSAGE, "Auto tune cancelled because temperature is not increasing\n");
 				break;
 			}
 
-			const uint32_t timeoutMinutes = (heater == reprap.GetHeat().GetBedHeater() || heater == reprap.GetHeat().GetChamberHeater()) ? 20 : 5;
-			if (heatingTime >= timeoutMinutes * 60 * 1000)
+			const uint32_t timeoutMinutes = (isBedOrChamberHeater) ? 20 : 5;
+			if (heatingTime >= timeoutMinutes * 60 * (uint32_t)SecondsToMillis)
 			{
 				platform.Message(GENERIC_MESSAGE, "Auto tune cancelled because target temperature was not reached\n");
 				break;
@@ -716,98 +712,6 @@ void PID::DoTuningStep()
 
 	// If we get here, we have finished
 	SwitchOff();								// sets mode and lastPWM, also deletes tuningTempReadings
-#else
-	if (temperature > tuningMaxTemp)
-	{
-		platform.MessageF(GENERIC_MESSAGE,
-				"Auto tune of heater %u with P=%.2f S=%.1f cancelled because temperature limit exceeded. Use lower P or higher S in m303 command.\n",
-				heater, tuningPwm, tuningTargetTemp);
-	}
-	else
-	{
-		switch(mode)
-		{
-		case HeaterMode::tuning0:
-			// Waiting for initial temperature to settle after any thermostatic fans have turned on
-			if (ReadingsStable(6000/platform.HeatSampleInterval(), 0.5))	// expect temperature to be stable within a 0.5C band for 6 seconds
-			{
-				// Starting temperature is stable, so move on
-				tuningReadingsTaken = 1;
-				tuningTempReadings[0] = tuningStartTemp = temperature;
-				timeSetHeating = tuningPhaseStartTime = millis();
-				lastPwm = tuningPwm;										// turn on heater at specified power
-				tuningReadingInterval = platform.HeatSampleInterval();		// reset sampling interval
-				mode = HeaterMode::tuning1;
-				return;
-			}
-			if (millis() - tuningPhaseStartTime < 20000)
-			{
-				// Allow up to 20 seconds for starting temperature to settle
-				return;
-			}
-			platform.Message(GENERIC_MESSAGE, "Auto tune cancelled because starting temperature is not stable\n");
-			break;
-
-		case HeaterMode::tuning1:
-			if (millis() - tuningPhaseStartTime > (uint32_t)(model.GetDeadTime() * SecondsToMillis) + 30000 && (temperature - tuningStartTemp) < 3.0)
-			{
-				platform.Message(GENERIC_MESSAGE, "Auto tune cancelled because temperature is not increasing\n");
-				break;
-			}
-
-			// If we have a reasonable number of readings, try to identify the point of maximum rate of temperature increase
-			if (tuningReadingsTaken >= 50)
-			{
-				const size_t index = GetMaxRateIndex();
-				if (index <= tuningReadingsTaken/2)
-				{
-					// We have found the point of inflection, so start the next phase
-					if (reprap.Debug(moduleHeat))
-					{
-						DisplayBuffer("At phase 1 end");
-					}
-					tuningTimeOfFastestRate = index * tuningReadingInterval * MillisToSeconds;
-					tuningFastestRate = (tuningTempReadings[index + 2] - tuningTempReadings[index - 2]) / (tuningReadingInterval * 4 * MillisToSeconds);
-
-					// Move the readings down so as to start at the max rate index
-					tuningPhaseStartTime += index * tuningReadingInterval;
-					tuningReadingsTaken -= index;
-					for (size_t i = 0; i < tuningReadingsTaken; ++i)
-					{
-						tuningTempReadings[i] = tuningTempReadings[i + index];
-					}
-					mode = HeaterMode::tuning2;
-				}
-			}
-			return;
-
-		case HeaterMode::tuning2:
-			// Note: there is no check for temperature increasing here, because it may increase very slowly towards the end of the tuning process.
-			{
-				// In the following, the figure of 2.75 was chosen because a value of 2 is too low to handle the bed heater
-				// with embedded thermistor on my Kossel (reservoir effect)
-				if (ReadingsStable(tuningReadingsTaken/2, (temperature - tuningTempReadings[0]) * 0.2))		// if we have been going for ~2.75 time constants
-				{
-					// We have been heating for long enough, so we can do a fit
-					FitCurve();
-					break;
-				}
-				else
-				{
-					return;
-				}
-			}
-			break;
-
-		default:
-			// Should not happen, but if it does then quit
-			break;
-		}
-	}
-
-	// If we get here, we have finished
-	SwitchOff();								// sets mode and lastPWM, also deletes tuningTempReadings
-#endif
 }
 
 // Return true if the last 'numReadings' readings are stable
@@ -830,8 +734,6 @@ void PID::DoTuningStep()
 	return maxReading - minReading <= maxDiff;
 }
 
-#ifdef NEW_TUNING
-
 // Calculate which reading gave us the peak temperature.
 // Return -1 if peak not identified yet, 0 if we failed to find a peak, else the index of the peak (which can't be zero because we always average 3 readings)
 /*static*/ int PID::GetPeakTempIndex()
@@ -916,78 +818,6 @@ void PID::CalculateModel()
 	}
 }
 
-#else
-
-// Return the index in the temperature readings of the maximum rate of increase
-// In view of the poor resolution of most thermistors at low temperatures, we measure over 4 time intervals instead of 2.
-/*static*/ size_t PID::GetMaxRateIndex()
-{
-	size_t index = 2;
-	float maxIncrease = 0.0;
-	for (size_t i = 2; i + 2 < tuningReadingsTaken; ++i)
-	{
-		const float increase = tuningTempReadings[i + 2] - tuningTempReadings[i - 2];
-		if (increase > maxIncrease)
-		{
-			maxIncrease = increase;
-			index = i;
-		}
-	}
-	return index;
-}
-
-// Calculate G, td and tc from the accumulated readings and print the auto tune success/fail message
-// Before calling this we must have already identified the point of inflection and re-based the readings to start at it.
-void PID::FitCurve()
-{
-	if (reprap.Debug(moduleHeat))
-	{
-		DisplayBuffer("At completion");
-	}
-
-	// We need 3 points equally-spaced in time to do the calculation
-	const size_t lowIndex = 0;
-	size_t highIndex = tuningReadingsTaken - 1;
-	if ((highIndex - lowIndex) % 2 != 0)
-	{
-		--highIndex;
-	}
-
-	// Calculate tc, td, G
-	const float T1 = tuningTempReadings[lowIndex] - tuningStartTemp;
-	const size_t midIndex = (lowIndex + highIndex)/2;
-	const float T2 = tuningTempReadings[midIndex] - tuningStartTemp;
-	const float T3 = tuningTempReadings[highIndex] - tuningStartTemp;
-	//const float t1 = lowIndex * tuningReadingInterval * MillisToSeconds;
-	const float dt = (midIndex - lowIndex) * tuningReadingInterval * MillisToSeconds;
-	const float t3 = highIndex * tuningReadingInterval * MillisToSeconds;
-	const float tc = dt/log((T2 - T1)/(T3 - T2));
-
-	// In theory we should calculate the delay time like this:
-	// td = tc * log((T3 - T1)/(T3 * exp(-t1/tc) - T1 * exp(-t3/tc)));
-	// However, the calculated td is highly inaccurate in some situations e.g. bed heater with reservoir effect.
-	// Better to estimate it from the point of inflection.
-	const float td = tuningTimeOfFastestRate - (tuningTempReadings[0] - tuningStartTemp)/tuningFastestRate;
-
-	// I'm not sure which td value we should use to calculate the gain, but it probably doesn't make much difference because usually, td << t3.
-	const float gain = T3 / (lastPwm * (1.0 - exp((td - t3)/tc)));
-
-	tuned = SetModel(gain, tc, td, model.GetMaxPwm(), true);
-	if (tuned)
-	{
-		platform.MessageF(GENERIC_MESSAGE,
-				"Auto tune heater %d with PWM=%.2f completed in %u sec, maximum temperature reached %.1fC\n"
-				"Use M307 H%d to see the result\n",
-				heater, tuningPwm, (millis() - tuningBeginTime)/(uint32_t)SecondsToMillis, tuningTempReadings[tuningReadingsTaken - 1], heater);
-	}
-	else
-	{
-		platform.MessageF(GENERIC_MESSAGE, "Auto tune of heater %u failed due to bad curve fit (G=%.1f, tc=%.1f, td=%.1f)\n", heater, gain, tc, td);
-	}
-}
-
-#endif
-
 void PID::DisplayBuffer(const char *intro)
 {
 	OutputBuffer *buf;