Coconut Dryer

Overview

An intelligent coconut drying system designed for the Southern Luzon State University (SLSU) Lucban BSME program. This Arduino-based embedded system provides automated temperature, humidity, and moisture control for efficient coconut drying operations using PID control algorithms and real-time sensor monitoring.

Table of Contents

• Features
• System Architecture
• Hardware Components
• Software Dependencies
• Installation
• Usage
• Configuration
• Project Structure
• 3D Models and Manufacturing
• Technical Specifications
• Contributing
• License
• Developer

Features

Core Functionality

• Automated Drying Process: PID-controlled temperature regulation for optimal drying conditions
• Multi-Parameter Monitoring: Real-time tracking of temperature, humidity, and moisture levels
• Smart Control System: Automatic shutdown when target moisture levels are achieved
• User Interface: 20x4 LCD display with intuitive menu navigation
• Status Indicators: Real-time system status and operational feedback

Technical Features

• PID Control Algorithm: Precise temperature control using industry-standard PID implementation
• Sensor Integration: SHT31 temperature/humidity sensor and soil moisture monitoring
• Relay Control: Multiple solid-state relay (SSR) control for heating elements and fans
• Push Button Interface: Multi-button navigation system for parameter adjustment
• Serial Monitoring: Real-time debugging and monitoring via serial communication

System Architecture

The system employs a modular architecture with separate components for different functionalities:

CoconutDryer.ino (Main Controller)
├── LCD_CONFIG.h (Display Management)
├── SHT31_CONFIG.h (Temperature/Humidity Sensor)
├── SOIL_MOISTURE_CONFIG.h (Moisture Monitoring)
├── RELAY_CONFIG.h (Actuator Control)
├── PID_CONFIG.h (Control Algorithm)
├── BUZZER_CONFIG.h (Audio Feedback)
├── PUSH_BUTTON_CONFIG.h (User Input)
└── LIB.h (Utility Functions)

Hardware Components

Essential Components

• Microcontroller: Arduino-compatible board (ESP32/Arduino Uno)
• Display: 20x4 I2C LCD (Address: 0x27)
• Temperature/Humidity Sensor: Adafruit SHT31 (I2C Address: 0x44)
• Moisture Sensor: Analog soil moisture sensor
• Relays: Multiple solid-state relays for heating elements and fans
• User Interface: Push button array for navigation
• Audio Feedback: Buzzer for system alerts

Power Requirements

• Operating Voltage: 5V/12V (depending on relay configuration)
• Power Consumption: Variable based on heating element usage
• Backup Power: Optional battery backup for data retention

Software Dependencies

Arduino Libraries

#include <LiquidCrystal_I2C.h>  // LCD display control
#include <Adafruit_SHT31.h>     // Temperature/humidity sensor
#include <PID_v1.h>             // PID control algorithm
#include <Wire.h>               // I2C communication

Installation Requirements

• Arduino IDE 1.8.x or higher
• ESP32/Arduino board support packages
• Required libraries (installable via Arduino Library Manager)

Installation

Hardware Setup

1. Circuit Assembly: Connect components according to the provided schematic
2. Sensor Calibration: Calibrate moisture sensors for coconut-specific readings
3. Relay Configuration: Set up solid-state relays for heating elements and fans
4. Display Connection: Wire I2C LCD to appropriate pins

Software Installation

1. Clone Repository:

   git clone https://github.com/qppd/coconut-dryer.git
   cd coconut-dryer

2. Open Arduino IDE: Load source/CoconutDryer/CoconutDryer.ino

3. Install Dependencies: Install required libraries via Library Manager

4. Board Configuration: Select appropriate board and port

5. Upload Firmware: Compile and upload to microcontroller

Usage

Initial Setup

1. Power On: Connect power supply and initialize system
2. Calibration: Allow sensors to stabilize (approximately 30 seconds)
3. Parameter Setting: Use push buttons to set desired parameters:
   • Temperature Setpoint: Default 60°C
   • Humidity Setpoint: Default 20%
   • Moisture Setpoint: Default 6%

Operation Modes

• Standby Mode: System monitoring without active drying
• Drying Mode: Active temperature control and moisture monitoring
• Completion Mode: Automatic shutdown when target moisture is achieved

Display Information

T:XX.X°C    SP:XX.X°C
H:XX.X%     SP:XX.X%
M:XX.X%     SP:XX.X%
Status: [Standby/Drying]

Configuration

PID Parameters

Located in PID_CONFIG.h:

double THRESHOLD_1 = 4;   // Proportional gain
double THRESHOLD_2 = 0;   // Integral gain
double THRESHOLD_3 = 22;  // Derivative gain

Sensor Calibration

Modify calibration constants in respective configuration files:

• SHT31: Temperature offset adjustment
• Moisture sensor: Analog-to-percentage conversion

Operational Parameters

Default setpoints can be modified in main code:

double TEMPERATURE_SETPOINT = 60;  // °C
double HUMIDITY_SETPOINT = 20;     // %
double MOISTURE_SETPOINT = 6;      // %

Project Structure

coconut-dryer/
├── LICENSE                          # Project license
├── README.md                        # Project documentation
├── models/                          # 3D models and manufacturing files
│   ├── gcode/                      # G-code files for 3D printing
│   │   ├── Coconut_Dryer_Board_Mount.gcode
│   │   ├── Coconut_Dryer_Button_Lock.gcode
│   │   ├── Coconut_Dryer_Case_Cover.gcode
│   │   └── Coconut_Dryer_Case.gcode
│   └── stl/                        # STL files for 3D printing
└── source/                         # Source code
    └── CoconutDryer/              # Main Arduino project
        ├── CoconutDryer.ino       # Main program file
        ├── BUZZER_CONFIG.h        # Audio feedback configuration
        ├── LCD_CONFIG.h           # Display configuration
        ├── LIB.h                  # Utility functions
        ├── PID_CONFIG.h           # PID control configuration
        ├── PUSH_BUTTON_CONFIG.h   # Input handling
        ├── RELAY_CONFIG.h         # Actuator control
        ├── SHT31_CONFIG.h         # Temperature/humidity sensor
        ├── SOIL_MOISTURE_CONFIG.h # Moisture sensor configuration
        ├── include/               # Header files
        │   ├── LCDController.h
        │   ├── MoistureSensor.h
        │   ├── RelayController.h
        │   └── TemperatureHumiditySensor.h
        └── src/                   # Implementation files
            ├── LCDController.cpp
            ├── MoistureSensor.cpp
            ├── RelayController.cpp
            └── TemperatureHumiditySensor.cpp

3D Models and Manufacturing

Available Models

The project includes complete 3D models for manufacturing:

• Board Mount: Secure mounting for electronic components
• Button Lock: User interface protection and organization
• Case Cover: Protective housing for the control system
• Main Case: Primary enclosure for all components

Manufacturing Files

• STL Files: Ready for 3D printing on standard FDM printers
• G-code Files: Pre-sliced for common 3D printer configurations
• Material Recommendations: PLA or PETG for durability and temperature resistance

Technical Specifications

Operating Parameters

• Temperature Range: 0-100°C (sensor range)
• Humidity Range: 0-100% RH
• Moisture Detection: Analog sensing with percentage conversion
• Control Precision: ±0.1°C temperature control
• Response Time: <60 seconds for temperature stabilization

Communication Interfaces

• Serial: 9600 baud rate for debugging and monitoring
• I2C: For sensor and display communication
• Digital I/O: Push button inputs and relay outputs

Performance Characteristics

• Loop Interval: 500ms for real-time monitoring
• PID Update Rate: Synchronized with main loop
• Display Refresh: Real-time parameter updates
• Auto-completion: Moisture-based process termination

Contributing

We welcome contributions to improve the Coconut Dryer project. Please follow these guidelines:

Development Process

1. Fork the repository
2. Create a feature branch
3. Make your changes with proper documentation
4. Test thoroughly with hardware setup
5. Submit a pull request with detailed description

Code Standards

• Follow Arduino coding conventions
• Document all functions and major code blocks
• Test with actual hardware before submission
• Maintain backward compatibility when possible

License

This project is open source and available under the MIT License.

Developer

Sajed Lopez Mendoza - Full Stack Developer & IoT Specialist

Professional Background

• Location: Unisan, Quezon Province, Philippines
• Specialization: Embedded Systems, IoT Development, Full-Stack Web Development
• Experience: Freelance Developer at QPPD (Quezon Province Programmers/Developers)
• Education: Southern Luzon State University (SLSU) Lucban

Technical Expertise

• Embedded Systems: ESP32, Arduino, Raspberry Pi development
• IoT Solutions: Sensor integration, real-time monitoring systems
• Hardware Integration: 3D printing, PCB design, solar power systems
• Programming: C/C++, Python, JavaScript, PHP, Java
• Machine Learning: TensorFlow, AI-powered applications
• Mobile Development: Android applications with hardware integration

Notable Projects

• IoT Smart Fan: Intelligent climate control system
• IoT Bike Tracker: Solar-powered GPS tracking solution
• CNC Jog Trainer: GRBL-based CNC machine controller
• Smart Cabinet: Advanced automated storage solution
• Umbrella Holder: PID-controlled drying system

Contact Information

• Email: quezon.province.pd@gmail.com
• GitHub: github.com/qppd
• Portfolio: sajed-mendoza.onrender.com
• Facebook: facebook.com/qppd.dev
• Community: facebook.com/QUEZONPROVINCEDEVS

---

Project Status: Finished | Last Updated: November 2025 | Version: 1.0