#include #include #include /* A fully automatic coffee bean roaster (Arduino) * By Rutger * nightlife31@hotmail.com * See http://www.instructables.com/id/A-fully-automatic-coffee-bean-roaster-Arduino/ * * * The program does the following: * Display a welcome screen and waiting for you to push the button. Then it turns on the fan but not the heating coil and it allows * you to set the minimal fan speed at which the beans still move a little (you can lower it during the roasting as beans get lighter). * When you press the button again the heating coil is turned on and the roasting starts. The program continuously measures the * temperature and adjusts the fanspeed in order to match the set point. It will lower the fan speed to increase the temperature of the * beans of increase the fan speed to do the opposite. If the beans get more than 3 degrees above the set point the heating coil is * switched of, which will lower the temperature directly. The set point is updated along a profile that is set into the program. * First heat up to 150C and stay there for 1 minute, then slowly increase to 190C and stay there for 1 minute. Then slowly increase * the temperature again until the final temperature is reached. At this point, the fan is set on max and the heating is turned down. * The roaster stops when the beans are lowered to 40C. * * The roasting profile: * phase 1: heat up directly to 150C * phase 2: keep at 150C for 60s * phase 3: increase in 180s to 190C (13.3C/min) * phase 4: keep at 190C for 60s * phase 5: increase with 3C/min till final roasting temp (205C) * phase 6: cool down to 40C * */ int Tprofile; int Sprofile; int final; // coffee roasting profile 1 String profilename1 = " Brasil "; int TP1 [] = {190, 201, 215 }; // Temperature profile (phase 1, 2, 3, etc) int SP1 [] = { 0, 120, 300 }; // Time profile in seconds (phase 1, 2, 3, etc) first time interval should be 0! int FT1 = 214; // define final roasting temperature // coffee roasting profile 2 String profilename2 = "Columbia"; int TP2 [] = {195, 201, 215 }; // Temperature profile (phase 1, 2, 3, etc) int SP2 [] = { 0, 120, 300 }; // Time profile in seconds (phase 1, 2, 3, etc) first time interval should be 0! int FT2 = 214; // define final roasting temperature // coffee roasting profile 3 String profilename3 = "India"; int TP3 [] = {200, 201, 215 }; // Temperature profile (phase 1, 2, 3, etc) int SP3 [] = { 0, 120, 300 }; // Time profile in seconds (phase 1, 2, 3, etc) first time interval should be 0! int FT3 = 213; // define final roasting temperature // coffee roasting profile 4 String profilename4 = "Ethiopia"; int TP4 [] = {205, 201, 215 }; // Temperature profile (phase 1, 2, 3, etc) int SP4 [] = { 0, 120, 300 }; // Time profile in seconds (phase 1, 2, 3, etc) first time interval should be 0! int FT4 = 214; // define final roasting temperature int cool = 40; // temperature to cool to after roasting int phase = 0; // phase int countdown; // count down seconds till end of phase int overshoot = 3; // max Temp overshoot before turn off heating coil float slope; // setpoint slope int serialTime; // determine phase //Calibrated setting temperature sensor //float a = 1,532; // y= aX - b //float b = 45; // PID controller #include double Input, Setpoint; // parameters for PID double Output = 0; int P = 75; //P term int I = 50; //I term int D = 0; //D term PID myPID(&Input, &Output, &Setpoint ,P ,I ,D, DIRECT); // initialize the library by associating any needed LCD interface pin // with the arduino pin number it is connected to const int rs = 12, en = 11, d4 = 13, d5 = 4, d6 = 3, d7 = 2; LiquidCrystal lcd(rs, en, d4, d5, d6, d7); ////////////////// int termoSO = 6; int termoCS = 7; int termoCLK = 8; MAX6675 thermocouple(termoCLK, termoCS, termoSO); /////////// int vccPin = 3; int gndPin = 2; // connections to Arduino int buttonpin = 9; // button connected to digital pin 9 int potpin = 0; // potmeter connected to analog in pin 0 //int temppin = 2; // temperature sensor connected to analog in pin 5 int fanpin = 10; // fan motor connected to pwm pin 10 int roastpin = 5; // heating coil relais connected to pin 5 // variables int temp; // Temperature in Celsius integer version of setpoint for LCD int SetP; // integer version of setpoint for LCD int readpot; // the current reading from the potmeter pin int fan = 255; // speed of fan motor int minfan=60; // minimal speed fanmotor int Output2; // takes the reverse of the output int readbutton = 0; // the current reading from the button pin int readtemp; // the current reading from the temp pin void setup() // run once, when the sketch starts { myPID.SetMode(AUTOMATIC); //turn the PID on lcd.clear(); // clear LCD screen Serial.begin(9600); // open serial communication lcd.begin(16, 2); lcd.setCursor(0, 0); lcd.print("Prazickavy"); lcd.setCursor(0,1); lcd.print("Verzia 2.0"); pinMode(vccPin, OUTPUT); digitalWrite(vccPin, HIGH); pinMode(gndPin, OUTPUT); digitalWrite(gndPin, LOW); pinMode(buttonpin, INPUT); // sets the digital pin as input pinMode(fanpin, OUTPUT); // sets the digital pin as output pinMode(roastpin, OUTPUT); // sets the digital pin as output // Press button to start roaster and select min fanspeed while (readbutton == LOW) { readbutton = digitalRead(buttonpin); }; delay (1000); readbutton = LOW; readpot = analogRead(potpin); // read potmeter value to set setpoint lcd.clear(); // clear LCD screen lcd.print("Select minimal"); lcd.setCursor(0,1); lcd.print("fan speed "); // Select min fanspeed until button press while (readbutton == LOW) { readpot = analogRead(potpin); // read potmeter value to set setpoint minfan = map (readpot,0,1023,0,255); // set minfan as the value determined by the potmeter analogWrite (fanpin,minfan); readbutton = digitalRead(buttonpin); }; delay (1000); readbutton = LOW; // lcd.clear(); // clear LCD screen // lcd.print(readpot); // delay (5000); //select profile lcd.clear(); // clear LCD screen lcd.print("Vyber profil"); lcd.setCursor(0,1); lcd.print(profilename1); if (readbutton == LOW) { Tprofile = TP1; Sprofile = SP1; final = FT1; delay (5000); } else lcd.clear(); // clear LCD screen lcd.print("Vyber profil"); lcd.setCursor(0,1); lcd.print(profilename2); if (readbutton == LOW) { Tprofile = TP2; Sprofile = SP2; final = FT2; delay (5000); } else lcd.clear(); // clear LCD screen lcd.print("Vyber profil"); lcd.setCursor(0,1); lcd.print(profilename3); if (readbutton == LOW) { Tprofile = TP3; Sprofile = SP3; final = FT3; delay (5000); } else lcd.clear(); // clear LCD screen lcd.print("Vyber profil"); lcd.setCursor(0,1); lcd.print(profilename4); if (readbutton == LOW) { Tprofile = TP4; Sprofile = SP4; final = FT4; delay (5000); } } void loop() // run over and over again { // temp = thermocouple.readCelsius(); // read temperature value readtemp = thermocouple.readCelsius(); // read temperature value Input = 1.188 * readtemp - 23.706; // Korekcia čidla temp = Input; readpot = analogRead(potpin); // read potmeter value to set setpoint if (readpot < 1022) { minfan = map (readpot,0,1023,0,255); // set minfan as the value determined by the potmeter } else { if (temp <= 155) { minfan = 255; } if (155 < temp && temp <= 188) { minfan = 240; } if (188 < temp && temp <= 205) { minfan = 230; } if (205 < temp && temp <= 210) { minfan = 215; } if (temp > 210) { minfan = 180; } } // go directly to sp during phase 0 if (phase == 0) { Setpoint = Tprofile [phase]; // jump directly to setpoint in first phase if (temp >= (Setpoint - 2) ) { countdown=-1;} // start phase 1 when setpoint is reached } // if countdown ends, start new phase and count down if (countdown < 0) { phase = phase + 1; serialTime = millis () / 1000; serialTime = serialTime + (Sprofile [phase]); slope = ( (Tprofile [phase]) - (Tprofile [(phase - 1)]) ); slope = (slope / (Sprofile [phase])); } // determine setpoint during phase 1+ if (phase > 0) { countdown = serialTime - ((millis ())/1000); Setpoint = Tprofile [(phase - 1)] + (slope * ((Sprofile [phase]) - countdown)); } // PID controller adjusts fanspeed myPID.Compute(); Output2 = 255 - Output; //fanspeed needs to be controlled in opposite direction fan = map (Output2,0,255,minfan,255); analogWrite (fanpin,fan); // turn heating coil on as long as T is below setpoint + overshoot if (temp < (Setpoint + overshoot)) { digitalWrite (roastpin,HIGH); } else { digitalWrite (roastpin,LOW); } // write to LCD screen lcd.clear(); lcd.home(); lcd.print("F:"); lcd.print(phase); lcd.print(" SP:"); lcd.print(int(Setpoint)); lcd.print(" T:"); lcd.print(temp); //lcd.print(" ");// //lcd.print(readtemp);// lcd.setCursor(0,1); lcd.print("Fan:"); lcd.print(int(fan/2.55)); //give fanspeed in %, rounded lcd.print("%"); lcd.setCursor(7,1); lcd.print(" Time:"); lcd.print(countdown); //send-receive with processing for Front-End PID program SerialReceive(); SerialSend(); // readbutton = digitalRead(buttonpin); //stop roasting and start cooling beans if the button is pressed // When final temp is reached of button is pressed, cool beans and end // if (temp >= final || readbutton == HIGH) { if (temp >= final) { // turn of heating coil readbutton = LOW; Setpoint=cool; Output=255; analogWrite (fanpin,Output); digitalWrite (roastpin,LOW); while (Input >= cool) { // wait untill beans are cooled till ... // Input = thermocouple.readCelsius(); readtemp = thermocouple.readCelsius(); // read temperature value Input = 1.188 * readtemp - 23.706; // Korekcia čidla temp = Input; lcd.clear(); lcd.home(); lcd.print("Chladim"); lcd.setCursor(0,1); lcd.print(" Teplota:"); lcd.print(temp); SerialReceive(); SerialSend(); delay(2000); }; analogWrite (fanpin,0); // fanspeed to zero lcd.clear(); lcd.home(); lcd.print("Prazenie"); lcd.setCursor(0,1); lcd.print("ukoncene :-D"); while (1 >= 1) {delay(2000);};//eternal loop } // waits for 0.5 second delay(500); }