Project Documentation

Arduino Nano ESP32-Based Aquaponics Monitoring System with Battery Power

Circuit Documentation

Summary

This document provides a detailed overview of an aquaponics monitoring and control system. The system utilizes an Arduino Nano ESP32 microcontroller to interface with various sensors and a relay to control a water pump. The sensors include a TDS sensor, a pH meter, a dissolved oxygen (DO) sensor, a temperature sensor, and an AHT10 sensor for humidity and air temperature. A buck converter is used to regulate the power supply from a LiPo battery.

Component List

Arduino Nano ESP32
- Description: Microcontroller used to interface with sensors and control the relay.
- Pins: D12, D11, D10, D9, D8, D7, D6, D5, D4, D3, D2, GND, RST, RX0, TX1, D13, 3.3V, B0, A0, A1, A2, A3, A4, A5, A6, A7, VBUS, B1, VIN
DO Sensor
- Description: Sensor used to measure dissolved oxygen levels in water.
- Pins: Vcc, Gnd, Out
TDS Sensor
- Description: Sensor used to measure Total Dissolved Solids (TDS) in water.
- Pins: AI, GND, 5V
Temperature Sensor
- Description: Sensor used to measure water temperature.
- Pins: Temp GND Black, Temp VDD Red, Temp DQ Data Yellow
PH Meter
- Description: Sensor used to measure the pH level of water.
- Pins: Signal, VCC, GND
AHT10
- Description: Sensor used to measure humidity and air temperature.
- Pins: Vcc, Gnd, SCL, SDA
Buck Converter
- Description: Used to regulate the power supply from the LiPo battery.
- Pins: IN+, IN-, OUT+, OUT-
LiPo Battery 2200mAH 30c
- Description: Power source for the circuit.
- Pins: VCC, GND
Water Pump
- Description: Pump used to circulate water in the aquaponics system.
- Pins: positive, negative
1-Channel Relay (5V 10A)
- Description: Relay used to control the water pump.
- Pins: NC, signal, C, power, NO, ground

Wiring Details

Arduino Nano ESP32

D8 connected to 1-Channel Relay (5V 10A) signal pin
D5 connected to Temperature Sensor Temp DQ Data Yellow pin
A0 connected to TDS Sensor AI pin
A1 connected to DO Sensor Out pin
A3 connected to PH Meter Signal pin
A4 connected to AHT10 SDA pin
A5 connected to AHT10 SCL pin

DO Sensor

Vcc connected to Buck Converter OUT+ pin
Gnd connected to Buck Converter OUT- pin
Out connected to Arduino Nano ESP32 A1 pin

TDS Sensor

AI connected to Arduino Nano ESP32 A0 pin
GND connected to Buck Converter OUT- pin
5V connected to Buck Converter OUT+ pin

Temperature Sensor

Temp GND Black connected to Buck Converter OUT- pin
Temp VDD Red connected to Buck Converter OUT+ pin
Temp DQ Data Yellow connected to Arduino Nano ESP32 D5 pin

PH Meter

Signal connected to Arduino Nano ESP32 A3 pin
VCC connected to Buck Converter OUT+ pin
GND connected to Buck Converter OUT- pin

AHT10

Vcc connected to Buck Converter OUT+ pin
Gnd connected to Buck Converter OUT- pin
SCL connected to Arduino Nano ESP32 A5 pin
SDA connected to Arduino Nano ESP32 A4 pin

Buck Converter

OUT+ connected to PH Meter VCC pin, DO Sensor Vcc pin, Temperature Sensor Temp VDD Red pin, 1-Channel Relay (5V 10A) power pin, TDS Sensor 5V pin, AHT10 Vcc pin
OUT- connected to PH Meter GND pin, DO Sensor Gnd pin, Temperature Sensor Temp GND Black pin, TDS Sensor GND pin, AHT10 Gnd pin
IN+ connected to LiPo Battery 2200mAH 30c VCC pin, 1-Channel Relay (5V 10A) C pin
IN- connected to LiPo Battery 2200mAH 30c GND pin, Water Pump negative pin, 1-Channel Relay (5V 10A) ground pin

LiPo Battery 2200mAH 30c

VCC connected to Buck Converter IN+ pin
GND connected to Buck Converter IN- pin

Water Pump

positive connected to 1-Channel Relay (5V 10A) NO pin
negative connected to Buck Converter IN- pin

1-Channel Relay (5V 10A)

signal connected to Arduino Nano ESP32 D8 pin
C connected to Buck Converter IN+ pin
power connected to Buck Converter OUT+ pin
NO connected to Water Pump positive pin
ground connected to Buck Converter IN- pin

Code Documentation

#include <Wire.h>
#include <OneWire.h>
#include <DallasTemperature.h>
#include <AHT10.h>
#include <DFRobot_ESP_PH.h>
#include <DFRobot_DO.h> // Added dissolved oxygen sensor library

// Pin Definitions
#define TDS_SENSOR_PIN A0
#define PH_SENSOR_PIN A3
#define DS18B20_PIN 5
#define RELAY_PIN 8
#define ONE_WIRE_BUS DS18B20_PIN
#define DO_SENSOR_PIN A1 // Added pin for dissolved oxygen sensor
#define SCL_PIN A5 // Typical SCL pin for I2C
#define SDA_PIN A4 // Typical SDA pin for I2C

// Sensor Objects
OneWire oneWire(ONE_WIRE_BUS);
DallasTemperature tempSensor(&oneWire);
AHT10 aht10;
DFRobot_ESP_PH ph;
DFRobot_DO do_sensor; // Dissolved oxygen sensor object
float tdsSensorValue = 0;
float phValue = 0;
float doValue = 0; // Dissolved oxygen value

void setup()
{
    Serial.begin(115200);

    // Initialize I2C with specific SCL and SDA pins
    Wire.begin(SDA_PIN, SCL_PIN);

    // Initialize Sensors
    tempSensor.begin();

    // AHT10 Initialization
    if (!aht10.begin())
    {
        Serial.println("AHT10 not found. Check wiring!");
    }

    // PH Sensor Initialization
    ph.begin();

    // Dissolved Oxygen Sensor Initialization
    do_sensor.begin();

    // Relay Setup
    pinMode(RELAY_PIN, OUTPUT);
    digitalWrite(RELAY_PIN, LOW);
}

void loop()
{
    // Read Temperature Sensors
    tempSensor.requestTemperatures();
    float waterTemp = tempSensor.getTempCByIndex(0);

    // Read AHT10 (Humidity and Air Temperature)
    float humidity = aht10.readHumidity();
    float airTemp = aht10.readTemperature();

    // Read TDS Sensor
    tdsSensorValue = readTDSSensor();

    // Read PH Sensor
    phValue = readPHSensor();

    // Read Dissolved Oxygen Sensor
    doValue = readDOSensor(waterTemp);

    // Print Sensor Readings
    Serial.println("--- Aquaponics Sensor Readings ---");
    Serial.print("Water Temperature: ");
    Serial.print(waterTemp);
    Serial.println(" °C");

    Serial.print("Air Temperature: ");
    Serial.print(airTemp);
    Serial.println(" °C");

    Serial.print("Humidity: ");
    Serial.print(humidity);
    Serial.println(" %");

    Serial.print("TDS Value: ");
    Serial.print(tdsSensorValue);
    Serial.println(" ppm");

    Serial.print("PH Value: ");
    Serial.print(phValue);
    Serial.println("");

    Serial.print("Dissolved Oxygen: ");
    Serial.print(doValue);
    Serial.println(" mg/L");

    // Control Relay (example: turn on if water temp is below 20°C)
    if (waterTemp < 20.0)
    {
        digitalWrite(RELAY_PIN, HIGH);
    }
    else
    {
        digitalWrite(RELAY_PIN, LOW