Smart Plant Watering System

/*
 * Project L14_04_PlantWater
 * Description: Smart Plant Watering System
 * Author: Christian Chavez
 * Date: 11-09-2020
 */


#include <Adafruit_MQTT.h>

#include "Adafruit_MQTT/Adafruit_MQTT.h" 
#include "Adafruit_MQTT/Adafruit_MQTT_SPARK.h" 
#include "Adafruit_MQTT/Adafruit_MQTT.h" 

#include "credentials.h"

#include <Adafruit_BME280.h>
#include <Adafruit_SSD1306.h>

#include "Air_Quality_Sensor.h"

#define OLED_RESET D4

Adafruit_SSD1306 display(OLED_RESET);

Adafruit_BME280 bme;

AirQualitySensor sensor(A4);

TCPClient TheClient; 
 
Adafruit_MQTT_SPARK mqtt(&TheClient,AIO_SERVER,AIO_SERVERPORT,AIO_USERNAME,AIO_KEY); 

Adafruit_MQTT_Subscribe buttonState = Adafruit_MQTT_Subscribe(&mqtt, AIO_USERNAME "/feeds/buttonOnOff"); 
Adafruit_MQTT_Publish soilRead = Adafruit_MQTT_Publish(&mqtt, AIO_USERNAME "/feeds/Soil Moisture"); 
Adafruit_MQTT_Publish tempRead = Adafruit_MQTT_Publish(&mqtt, AIO_USERNAME "/feeds/Temperature Reading");
Adafruit_MQTT_Publish pressureRead = Adafruit_MQTT_Publish(&mqtt, AIO_USERNAME "/feeds/Pressure Reading");
Adafruit_MQTT_Publish humidityRead = Adafruit_MQTT_Publish(&mqtt, AIO_USERNAME "/feeds/Humidity Reading");
Adafruit_MQTT_Publish airRead = Adafruit_MQTT_Publish(&mqtt, AIO_USERNAME "/feeds/Air Quality Reading");
Adafruit_MQTT_Publish dustRead = Adafruit_MQTT_Publish(&mqtt, AIO_USERNAME "/feeds/Dust Reading");

float temp;
float pressure;
float humidity;
unsigned long last;
unsigned long lastTime;
unsigned long pumpLastTime;
unsigned long dustStartTime;
unsigned long duration;
int capRead; //stores capacitive soil sensor reading
int value; //stores value subcribed from adafruit.io
int airQuality; //stores value from Air Quality Sensor
int slopeQuality;
char dangerReading;
int dust;
float lowPulseOccupancy;

float concentration = 0;
float realConcentration;
float ratio;

const int ledPin = D7; //pin to turn on Particle led 
const int soilPin = A1; 
const int dustPin = A3;
const int airPin = A4;
const int pumpPin = A5;

void setup() {
  Serial.begin(9600);
  display.begin(SSD1306_SWITCHCAPVCC, 0x3C);
  display.display();
  delay(2000);

  bme.begin(0x76);

  if (sensor.init()) {
      Serial.printf("Sensor ready.");
  } else {
      Serial.printf("Sensor ERROR!");
  }  

  mqtt.subscribe(&buttonState);

  pinMode(soilPin, INPUT);
  pinMode(pumpPin, OUTPUT);
  pinMode(ledPin, OUTPUT);
  pinMode(airPin, INPUT);
  pinMode(dustPin, INPUT);

  dustStartTime = millis();
}

void loop() {

  duration = pulseIn(dustPin, LOW);
  lowPulseOccupancy = lowPulseOccupancy + duration;
  if ((millis()-dustStartTime) >= 30000){
    ratio = lowPulseOccupancy/(30000*10.0);
    concentration = 1.1*pow(ratio,3)-3.8*pow(ratio,2)+520*ratio+0.62;
    if(concentration > 1){
      realConcentration = concentration;
    }
    Serial.printf("Concentration = %f pcs/0.01cf",realConcentration);
    lowPulseOccupancy = 0;
    dustStartTime = millis();
  }

  int slopeQuality = sensor.slope();
  if (slopeQuality == AirQualitySensor::FORCE_SIGNAL) {
  Serial.println("High pollution! Force signal active.");
  }
  else if (slopeQuality == AirQualitySensor::HIGH_POLLUTION) {
    Serial.println("High pollution!");
  }
  else if (slopeQuality == AirQualitySensor::LOW_POLLUTION) {
    Serial.println("Low pollution!");
  }
  else if (slopeQuality == AirQualitySensor::FRESH_AIR) {
    Serial.println("Fresh air.");
  }

  display.clearDisplay();
  display.setRotation(2);
  display.setTextSize(1);
  display.setTextColor(WHITE);
  display.setCursor(0,0);
  temp = ((bme.readTemperature()*9/5)+32);
  pressure = ((bme.readPressure()/100)*0.03);
  humidity = bme.readHumidity();
  airQuality = sensor.getValue();

  display.printf("Soil: %i\nTemp: %.2f%c\nPressure: %.2f\nHumidity: %.2f%c\nAir Quality: %i\nDust: %.2f\n",capRead,temp,(char)247,pressure,humidity,(char)37,airQuality,realConcentration);
  display.display();

  MQTT_connect();

  if ((millis()-last)>5000) {
      Serial.printf("Pinging MQTT \n");
      if(! mqtt.ping()) {
        Serial.printf("Disconnecting \n");
        mqtt.disconnect();
      }
      last = millis();
  }
 
  Adafruit_MQTT_Subscribe *subscription;
  while ((subscription = mqtt.readSubscription(10000))) {
    if (subscription == &buttonState) {
      value = atof((char *)buttonState.lastread);
      if(value == 1){
      digitalWrite(ledPin, HIGH);
      digitalWrite(pumpPin, HIGH);
      }
      else{
      digitalWrite(ledPin, LOW);
      digitalWrite(pumpPin, LOW);
      }
    }
  }

  if((millis()-lastTime > 30000)) {
    if(mqtt.Update()) {
      analogWrite(pumpPin, HIGH);
      capRead = analogRead(soilPin);
      soilRead.publish(capRead);
      tempRead.publish(temp);
      pressureRead.publish(pressure);
      humidityRead.publish(humidity);
      airRead.publish(airQuality);
      dustRead.publish(concentration);
      Serial.printf("Soil Read: %i Temp: %f Pressure: %f Humidity %f Air Quality: %i Dust: %f\n",capRead,temp,pressure,humidity, airQuality, concentration); 
      } 
    lastTime = millis();
  }

  if((millis()-pumpLastTime > 60000)) { //automatic plant watering 
    if(capRead > 1600){
    digitalWrite(pumpPin, HIGH);
    digitalWrite(ledPin, HIGH);
    Serial.printf("Watering plant\n");
    delay(1000);
    digitalWrite(pumpPin, LOW);
    digitalWrite(ledPin, LOW);
    Serial.printf("Stop Watering plant\n");
    }
    pumpLastTime = millis();
  }

}

void MQTT_connect() {
  int8_t ret;
 
  if (mqtt.connected()) {
    return;
  }
 
  Serial.print("Connecting to MQTT... ");
 
  while ((ret = mqtt.connect()) != 0) { // connect will return 0 for connected
       Serial.println(mqtt.connectErrorString(ret));
       Serial.println("Retrying MQTT connection in 5 seconds...");
       mqtt.disconnect();
       delay(5000);  // wait 5 seconds
  }
  Serial.println("MQTT Connected!");
}