From c583fea17c175565215cfe71ce31e6444a2c765e Mon Sep 17 00:00:00 2001 From: miguel5612 Date: Sat, 28 Mar 2020 08:42:25 -0500 Subject: [PATCH] Added MQ4 all gases --- examples/MQ-4-ALL/MQ-4-ALL.ino | 117 +++++++++++++++++++++++++++++++++ 1 file changed, 117 insertions(+) create mode 100644 examples/MQ-4-ALL/MQ-4-ALL.ino diff --git a/examples/MQ-4-ALL/MQ-4-ALL.ino b/examples/MQ-4-ALL/MQ-4-ALL.ino new file mode 100644 index 0000000..0bc6dcf --- /dev/null +++ b/examples/MQ-4-ALL/MQ-4-ALL.ino @@ -0,0 +1,117 @@ +/* + MQUnifiedsensor Library - reading an MQ4 + + Demonstrates the use a MQ4 sensor. + Library originally added 01 may 2019 + by Miguel A Califa, Yersson Carrillo, Ghiordy Contreras, Mario Rodriguez + + Added example + modified 23 May 2019 + by Miguel Califa + + Updated library usage + modified 26 March 2020 + by Miguel Califa + + This example code is in the public domain. + +*/ + +//Include the library +#include + +//Definitions +#define placa "Arduino UNO" +#define Voltage_Resolution 5 +#define pin A0 //Analog input 0 of your arduino +#define type "MQ-4" //MQ4 +#define ADC_Bit_Resolution 10 // For arduino UNO/MEGA/NANO +#define RatioMQ4CleanAir 4.4 //RS / R0 = 4.4 ppm +//#define calibration_button 13 //Pin to calibrate your sensor + +//Declare Sensor +MQUnifiedsensor MQ4(placa, Voltage_Resolution, ADC_Bit_Resolution, pin, type); + +void setup() { + //Init the serial port communication - to debug the library + Serial.begin(9600); //Init serial port + + //Set math model to calculate the PPM concentration and the value of constants + MQ4.setRegressionMethod(1); //_PPM = a*ratio^b + /* + Exponential regression: + Gas | a | b + LPG | 3811.9 | -3.113 + CH4 | 1012.7 | -2.786 + CO | 200000000000000 | -19.05 + Alcohol| 60000000000 | -14.01 + smoke | 30000000 | -8.308 + */ + + + + /***************************** MQ CAlibration ********************************************/ + // Explanation: + // In this routine the sensor will measure the resistance of the sensor supposing before was pre-heated + // and now is on clean air (Calibration conditions), and it will setup R0 value. + // We recomend execute this routine only on setup or on the laboratory and save on the eeprom of your arduino + // This routine not need to execute to every restart, you can load your R0 if you know the value + // Acknowledgements: https://jayconsystems.com/blog/understanding-a-gas-sensor + Serial.print("Calibrating please wait."); + float calcR0 = 0; + for(int i = 0; i<=10; i ++) + { + MQ4.update(); // Update data, the arduino will be read the voltage on the analog pin + calcR0 += MQ4.calibrate(RatioMQ4CleanAir); + Serial.print("."); + } + MQ4.setR0(calcR0/10); + Serial.println(" done!."); + + if(isinf(calcR0)) {Serial.println("Warning: Conection issue founded, R0 is infite (Open circuit detected) please check your wiring and supply"); while(1);} + if(calcR0 == 0){Serial.println("Warning: Conection issue founded, R0 is zero (Analog pin with short circuit to ground) please check your wiring and supply"); while(1);} + /***************************** MQ CAlibration ********************************************/ + + /* + //If the RL value is different from 10K please assign your RL value with the following method: + MQ4.setRL(10); + */ + + /***************************** MQ Init ********************************************/ + //Input: setup flag, if this function are on setup will print the headers (Optional - Default value: False) + //Output: print on serial port the information about sensor and sensor readings + //Remarks: Configure the pin of arduino as input. + /************************************************************************************/ + MQ4.init(); + + Serial.println("*************************** Lectures from MQ-board ***************************"); + Serial.println("| LPG | CH4 | CO | Alcohol | Smoke |"); +} + +void loop() { + MQ4.update(); // Update data, the arduino will be read the voltage on the analog pin + + MQ4.setA(3811.9); MQ4.setB(-3.113); // Configurate the ecuation values to get CH4 concentration + float LPG = MQ4.readSensor(); // Sensor will read PPM concentration using the model and a and b values setted before or in the setup + + MQ4.setA(1012.7); MQ4.setB(-2.786); // Configurate the ecuation values to get CH4 concentration + float CH4 = MQ4.readSensor(); // Sensor will read PPM concentration using the model and a and b values setted before or in the setup + + MQ4.setA(200000000000000); MQ4.setB(-19.05); // Configurate the ecuation values to get CH4 concentration + float CO = MQ4.readSensor(); // Sensor will read PPM concentration using the model and a and b values setted before or in the setup + + MQ4.setA(60000000000); MQ4.setB(-14.01); // Configurate the ecuation values to get CH4 concentration + float Alcohol = MQ4.readSensor(); // Sensor will read PPM concentration using the model and a and b values setted before or in the setup + + MQ4.setA(30000000); MQ4.setB(-8.308); // Configurate the ecuation values to get CH4 concentration + float Smoke = MQ4.readSensor(); // Sensor will read PPM concentration using the model and a and b values setted before or in the setup + + Serial.print("| "); Serial.print(LPG); + Serial.print(" | "); Serial.print(CH4); + Serial.print(" | "); Serial.print(CO); + Serial.print(" | "); Serial.print(Alcohol); + Serial.print(" | "); Serial.print(Smoke); + Serial.println(" |"); + + delay(500); //Sampling frequency +} \ No newline at end of file