//Include the library #include /* This program was made to test the algorithm that from the ratio obtains the PPM (The core of this library), regardless of the plate in which the result is executed should give a small error (ideally less than 5%), is our way of self-evaluation, we tell the library what is the value of the ratio and ask him to calculate the PPM and compare it against the value that should really give, these values were taken from the same datasheet with which the library was made. */ //Definitions #define placa "Arduino Mega 2560" #define Voltage_Resolution 5 #define type "MQ-Board" #define ADC_Bit_Resolution 10 // For arduino UNO/MEGA/NANO #define pin2 A2 //Analog input 2 of your arduino #define pin3 A3 //Analog input 3 of your arduino #define pin4 A4 //Analog input 4 of your arduino #define pin5 A5 //Analog input 5 of your arduino #define pin6 A6 //Analog input 6 of your arduino #define pin7 A7 //Analog input 7 of your arduino #define pin8 A8 //Analog input 8 of your arduino #define pin9 A9 //Analog input 9 of your arduino //#define calibration_button 13 //Pin to calibrate your sensor //Declare Sensor MQUnifiedsensor MQ2(placa, Voltage_Resolution, ADC_Bit_Resolution, pin2, type); MQUnifiedsensor MQ3(placa, Voltage_Resolution, ADC_Bit_Resolution, pin3, type); MQUnifiedsensor MQ4(placa, Voltage_Resolution, ADC_Bit_Resolution, pin4, type); MQUnifiedsensor MQ5(placa, Voltage_Resolution, ADC_Bit_Resolution, pin5, type); MQUnifiedsensor MQ6(placa, Voltage_Resolution, ADC_Bit_Resolution, pin6, type); MQUnifiedsensor MQ7(placa, Voltage_Resolution, ADC_Bit_Resolution, pin7, type); MQUnifiedsensor MQ8(placa, Voltage_Resolution, ADC_Bit_Resolution, pin8, type); MQUnifiedsensor MQ9(placa, Voltage_Resolution, ADC_Bit_Resolution, pin9, type); int ratio[10] = {}; int expectedValue[10] = {}; void setup() { //Init serial port Serial.begin(9600); //init the sensor MQ2.init(); MQ2.setRegressionMethod("Exponential"); //_PPM = a*ratio^b MQ2.setA(574.25); MQ2.setB(-2.222); // Configurate the ecuation values to get LPG concentration MQ2.setR0(9.659574468); MQ3.init(); MQ3.setRegressionMethod("Exponential"); //_PPM = a*ratio^b MQ3.setA(4.8387); MQ3.setB(-2.68); // Configurate the ecuation values to get Benzene concentration MQ3.setR0(3.86018237); MQ4.init(); MQ4.setRegressionMethod("Exponential"); //_PPM = a*ratio^b MQ4.setA(1012.7); MQ4.setB(-2.786); // Configurate the ecuation values to get CH4 concentration MQ4.setR0(3.86018237); MQ5.init(); MQ5.setRegressionMethod("Exponential"); //_PPM = a*ratio^b MQ5.setA(1163.8); MQ5.setB(-3.874); // Configurate the ecuation values to get H2 concentration MQ5.setR0(71.100304); MQ6.init(); MQ6.setRegressionMethod("Exponential"); //_PPM = a*ratio^b MQ6.setA(2127.2); MQ6.setB(-2.526); // Configurate the ecuation values to get CH4 concentration MQ6.setR0(13.4285714); MQ7.init(); MQ7.setRegressionMethod("Exponential"); //_PPM = a*ratio^b MQ7.setA(99.042); MQ7.setB(-1.518); // Configurate the ecuation values to get CO concentration MQ7.setR0(4); MQ8.init(); MQ8.setRegressionMethod("Exponential"); //_PPM = a*ratio^b MQ8.setA(976.97); MQ8.setB(-0.688); // Configurate the ecuation values to get H2 concentration MQ8.setR0(1); MQ9.init(); MQ9.setRegressionMethod("Exponential"); //_PPM = a*ratio^b MQ9.setA(1000.5); MQ9.setB(-2.186); // Configurate the ecuation values to get LPG concentration MQ9.setR0(9.42857143); //Print in serial monitor Serial.print("MQ2 to MQ9 - test program"); } void loop() { // Testing MQ2 LPG ratio = {}; expectedValue = {}; // Testing MQ3 Benzene // Testing MQ4 CH4 // Testing MQ5 H2 // Testing MQ6 CH4 // Testing MQ7 CO // Testing MQ8 H2 // Testing MQ9 LPG } double calculatePercentualError(double expectedValue, double calculatedValue) { // Return the diference between two measures return abs(calculatedValue-expectedValue)/expectedValue }