add under and over shoot corrections

README.md

@@ -141,4 +141,5 @@ ESP32Async/ESPAsyncWebServer	| https://github.com/ESP32Async/ESPAsyncWebServer |
 
 ### Display
 
-In the long run a capacative LCD screen might be used in addition to the WebSocket connection
+- Add capacative LCD screen to be used in addition to the WebSocket connection for direct control on the oven
+- Maybe add sensor to indicate if the lid has been opened

index.html

@@ -15,7 +15,7 @@
         <div class="card-grid">
             <div class="card">
                 <p class="card-title">
-                    Temperature</p>
+                    Sensor Temperature</p>
                 <p class="reading"><span id="temperature"></span> &deg;C</p>
             </div>
             <div class="card relais" id="relais_switch">
@@ -34,7 +34,7 @@
         <div class="oven" id="oven">
             <div class="oven-wrapper">
                 <div class="oven-img-wrapper">
-                    <img src="/oven.png">
+                    <img src="/oven_small.png">
                 </div>
             </div>
         </div>

src/main.cpp

@@ -31,10 +31,12 @@ int thermoCLK = 5;
 MAX6675 thermocouple(thermoCLK, thermoCS, thermoDO);
 
 int targetTemp = 300;
-int overShoot = 10;
-int underShoot = 5;
+float setOverShoot = 15;
+float setUnderShoot = 10;
+float derivedOverShoot = targetTemp;
+float derivedUnderShoot = targetTemp;
 unsigned long lastSwitch = 0;
-unsigned long switchDelay = 60000;
+unsigned long switchDelay = 30000; // 30s
 bool autoSwitch = true;
 
 // Get Sensor Readings and return JSON object
@@ -49,6 +51,9 @@ String getSensorReadings()
   {
     readings["relais"] = 0;
   }
+  readings["target_temp"] = targetTemp;
+  readings["derived_overshoot"] = derivedOverShoot;
+  readings["derived_undershoot"] = derivedUnderShoot;
   serializeJson(readings, jsonString);
   return jsonString;
 }
@@ -108,11 +113,12 @@ void handleWebSocketMessage(void *arg, uint8_t *data, size_t len)
         digitalWrite(relay, HIGH);
         lastSwitch = millis();
       }
+      resetDerivedValues();
     }
     if (message.startsWith("setTargetTemp"))
     {
       String target = message.substring(15, 18);
-      targetTemp = target.toInt();
+      targetTemp = target.toFloat();
       Serial.printf("\nTarget temp set to ");
       Serial.print(targetTemp);
       Serial.printf("°C");
@@ -145,6 +151,54 @@ void initWebSocket()
   server.addHandler(&ws);
 }
 
+void regulateRelais()
+{
+  if (autoSwitch)
+  {
+    if ((millis() - lastSwitch) > switchDelay)
+    {
+      float temperature = thermocouple.readCelsius();
+      float sinceLastSwitch = millis() - lastSwitch;
+      float fiveMinutesInMillis = 5 * 60 * 1000;
+      float shootFactor = sinceLastSwitch / fiveMinutesInMillis;
+
+      float overshoot = setOverShoot * shootFactor; // derive over 5 mins -> 1 min eq. 3°C, 5mins eq. 15°C
+      float dirivedOvershoot = min(overshoot, setOverShoot);
+
+      float undershoot = setUnderShoot * shootFactor; // derive over 5 min -> 1 min eq. 3°C, 5mins eq. 15°C
+      float dirivedUndershoot = min(undershoot, setUnderShoot);
+
+      float overShootCorrectedTarget = derivedOverShoot = targetTemp - dirivedOvershoot;
+      float underShootCorrectedTarget = derivedUnderShoot = targetTemp + dirivedUndershoot;
+
+      if (temperature > overShootCorrectedTarget) // > 285°C
+      {
+        if (digitalRead(relay) == HIGH)
+        {
+          digitalWrite(relay, LOW);
+          lastSwitch = millis();
+          resetDerivedValues();
+        }
+      }
+      else if (temperature < underShootCorrectedTarget) // < 310°C
+      {
+        if (digitalRead(relay) == LOW)
+        {
+          digitalWrite(relay, HIGH);
+          lastSwitch = millis();
+          resetDerivedValues();
+        }
+      }
+    }
+  }
+}
+
+void resetDerivedValues()
+{
+  derivedOverShoot = targetTemp;
+  derivedUnderShoot = targetTemp;
+}
+
 void setup()
 {
   Serial.begin(9600);
@@ -172,16 +226,7 @@ void loop()
   {
     String sensorReadings = getSensorReadings();
     notifyClients(sensorReadings);
-    if (((millis() - lastSwitch) > switchDelay) && thermocouple.readCelsius() >= (targetTemp - overShoot)) // >= 285°C
-    {
-      digitalWrite(relay, LOW);
-      lastSwitch = millis();
-    }
-    if (((millis() - lastSwitch) > switchDelay) && thermocouple.readCelsius() < (targetTemp - underShoot)) // < 270°C
-    {
-      digitalWrite(relay, HIGH);
-      lastSwitch = millis();
-    }
+    regulateRelais();
     lastTime = millis();
   }
 

src/main.ts

@@ -19,17 +19,17 @@ let ws: WebSocket;
 const now = new Date()
 
 let container: HTMLElement | null = document.querySelector('#plot')
-let temperatureData = [
-    [now.getTime(), 25]
-]
+
 
 let relais = 0
 let relaisData = [
     [now.getTime(), 0]
 ]
 
-let temp = 25;
-let targetTemp = 350
+let temp = 300;
+let targetTemp = 300
+let targetTempOverShoot = 300
+let targetTempUnderShoot = 300
 
 const oven = document.querySelector('#oven')
 const temperature = document.querySelector('#temperature')
@@ -42,6 +42,10 @@ let maxValues = 4 * 60 * 60 // 60 minutes (4 values/sec)
 let hs: Highcharts.StockChart;
 let hsOptions: Highcharts.Options
 
+let temperatureData = [
+    [now.getTime(), temp]
+]
+
 const getRelaisBands = () => {
     let relaisBands = []
     let active = false;
@@ -65,15 +69,18 @@ const getRelaisBands = () => {
 }
 
 const dashStyle: DashStyleValue = 'Dash'
-const getTargetLine = () => {
+const getTargetLines = () => {
     return [
-        { value: targetTemp, width: 3, dashStyle: dashStyle }
+        { value: targetTemp, width: 3, dashStyle: dashStyle },
+        { value: targetTempOverShoot, width: 1, dashStyle: dashStyle, color: "red" },
+        { value: targetTempUnderShoot, width: 1, dashStyle: dashStyle, color: "red" }
     ]
 }
 
 const createChart = () => {
     hsOptions = {
         chart: {
+            height: '650px',
             animation: {
                 duration: 250,
                 easing: 'linear'
@@ -121,7 +128,7 @@ const createChart = () => {
                 to: 600,
                 color: 'rgba(255, 0, 0, 0.4)'
             }],
-            plotLines: getTargetLine()
+            plotLines: getTargetLines()
         },
 
         xAxis: {
@@ -233,7 +240,7 @@ const onLoad = () => {
 
 
                 hs.xAxis[0].update({ plotBands: getRelaisBands() })
-                hs.yAxis[0].update({ plotLines: getTargetLine() })
+                hs.yAxis[0].update({ plotLines: getTargetLines() })
                 hs.series[0].setData(temperatureData, true)
             }, 250)
         }
@@ -302,10 +309,16 @@ const onMessage = (event: MessageEvent) => {
                 if (relaisSwitchInput)
                     relaisSwitchInput.checked = false
             }
+        } else if (key === 'target_temp') {
+            targetTemp = myObj[key]
+        } else if (key === 'derived_overshoot') {
+            targetTempOverShoot = myObj[key]
+        } else if (key === 'derived_undershoot') {
+            targetTempUnderShoot = myObj[key]
         }
 
         hs.xAxis[0].update({ plotBands: getRelaisBands() })
-        hs.yAxis[0].update({ plotLines: getTargetLine() })
+        hs.yAxis[0].update({ plotLines: getTargetLines() })
         hs.series[0].setData(temperatureData, true)
     }
 }
@@ -336,10 +349,10 @@ const switchRelais = () => {
 const changeTargetTemp = (e: Event) => {
     const target = e.target as HTMLTextAreaElement;
     let value = Number(target?.value)
-    targetTemp = value
-    console.log('Changed target temp to ' + targetTemp)
+    // targetTemp = value
+    console.log('Changed target temp to ' + value)
     if (!import.meta.env.DEV) {
-        ws.send("setTargetTemp: " + pad(targetTemp, 3));
+        ws.send("setTargetTemp: " + pad(value, 3));
     }
 }
 

src/styles.css

@@ -36,7 +36,7 @@ p {
 }
 
 .graph {
-    height: 310px;
+    height: 570px;
     overflow: hidden;
     display: flex;
     justify-content: center;