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Pet Feeder
Author: Perian Bianca-Luminita | Group: 331CB
Introduction
We all love our pets, but remembering to fill the bowl at the exact same time every day is just another task on a never-ending to-do list. So, here I am with the solution: an Automatic Pet Feeder. But what is it, exactly? It's a smart solution for a common problem. The device is designed to automate the feeding routine while keeping you in control. It features two main modes: an 'on-demand' option where your pet can trigger a snack using an IR sensor, and a manual option that lets you dispense food via a custom web interface from your phone. Beyond just dispensing food, the system monitors storage levels so you always know when it's time for a refill. It also tracks feeding history, letting you see exactly when the last meals were served. Most importantly, you have full control: if your pet is getting a bit too hungry, you can remotely disable the IR sensor through the interface to prevent overfeeding. So, now you have more time to play with your furry friend!
General Description
System Modules
- ESP32 Microcontroller: The “brain” that connects to Wi-Fi, processes sensor data, and coordinates the feeding schedule.
- SG90 Servo Motor: The mechanical actuator that opens the dispensing lid to release a precise portion of pet food.
- IR Obstacle Sensor: Allows the pet to “ask” for food; when the pet is near, the sensor triggers an automated snack.
- Ultrasonic Sensor: Measures the distance to the food inside the hopper to calculate the remaining percentage.
- LCD Display: Provides real-time status updates (e.g., “Feeding…”).
- Buzzer: Emits a sound notification to alert the pet that the meal has been served.
- Smart Status LEDs: A visual signaling system for food levels:
- Green: Sufficient food storage.
- Yellow: Medium level (refill soon).
- Red: Critical level (storage almost empty).
Hardware Design
Components List
- ESP32 DevKit V1 Board
- SG90 Servo Motor
- IR Obstacle Avoidance Sensor
- HC-SR04 Ultrasonic Distance Sensor
- 16×2 LCD with I2C Module
- Active Buzzer
- LEDs (Red, Yellow, Green)
- Resistors (220 Ohm)
- Breadboard
- Jumper Wires (M-M, M-F)
- Power Bank
Pin Mapping
This table describes the physical connections made on the breadboard between the ESP32 microcontroller and the system's peripherals:
| Component | ESP32 Pin | Interface |
|---|---|---|
| Ultrasonic Sensor (TRIG) | D5 | GPIO / Output |
| Ultrasonic Sensor (ECHO) | D18 | GPIO / Input |
| IR Sensor | D4 | GPIO / Input (Pull-up) |
| SG90 Servomotor | D13 | PWM / Output |
| Active Buzzer | D26 | GPIO / Output |
| Red LED | D32 | GPIO / Output |
| Yellow LED | D33 | GPIO / Output |
| Green LED | D25 | GPIO / Output |
| LCD1602 SDA | D21 | I2C (Data) |
| LCD1602 SCL | D22 | I2C (Clock) |
| Power Supply | VIN (5V) | Power Input |
Wokwi Simulation
I've developed this ESP32 project using the Wokwi simulator. Since the platform doesn't offer a dedicated IR proximity sensor, I used a push button to simulate the pet's arrival. This allowed me to fully test and perfect the logic for the LCD, LEDs, buzzer, and servo, ensuring the system is ready for a quick swap with a real IR sensor once I move to the physical build.
