Jeongwoo's Smart Water Dispenser

Demo Video

Motivation - Why did I build this?

Sometimes in life, you forget to do the simplest things. With a busy schedule ahead of you with school, sports, and constant distractions, I personally found myself frequently feeling exhausted and facing injuries due to lack of hyrdation. It wasn't intentional, but rahter just one of those basic needs that gets overlooked. Throughout this class, I wanted to create an object that could take care of this for me, something that would make hydration effortless. That's how the idea of Jeongwoo's Smart Water Dispenser started: a dispenser that combines convenience, automation, and health into one brilliant solution.

Main Function of my Project

My project is a water dispenser that pours water through a pump. It gets activated with a small button, and it exaclty pours water for 1 minute an 20 seconds (~ 135 ml)

Gallery

Downloadable Files

STL: Nozzle Mount

STL: Bottle Holder

Fusion 360 Project

Components Used

Seeeduino XIAO ESP32 microcontroller
Relay module (for 5V pump)
Submersible water pump
Ultrasonic sensor (HC-SR04)
I2C LCD 16x2
Pushbutton and buzzer

Wiring Diagram

Arduino Code (Generated with the help of AI technology)

Arduino Code


// Pin assignments
const int A1A = D6;         // Motor speed control
const int A1B = D7;         // Motor direction control
const int buttonPin = D2;   // Button input

bool isDispensing = false;
unsigned long dispenseStartTime = 0;

void setup() {
  pinMode(A1A, OUTPUT);
  pinMode(A1B, OUTPUT);
  pinMode(buttonPin, INPUT_PULLUP); // Button between D2 and GND

  digitalWrite(A1A, LOW);  // Ensure motor starts OFF
  digitalWrite(A1B, LOW);
  Serial.begin(9600);
}

void loop() {
  if (isDispensing) {
    // Check if 80 seconds have passed
    if (millis() - dispenseStartTime >= 80000) {
      digitalWrite(A1A, LOW);
      digitalWrite(A1B, LOW);
      isDispensing = false;
      Serial.println("done dispensing");
    }
  } else {
    Serial.println("waiting for button press");
    if (digitalRead(buttonPin) == LOW) {
      Serial.println("button pressed");
      digitalWrite(A1A, LOW);
      digitalWrite(A1B, HIGH);
      dispenseStartTime = millis();
      isDispensing = true;

      // Wait for button release
      while (digitalRead(buttonPin) == LOW) {
        Serial.println("button is still being pressed");
        delay(10);
      }
    }
  }
}

References

Future Improvements

Wi-Fi + app control integration
Rotary encoder for dynamic volume
Battery backup and water level monitor

Development Process

Here’s how I built, tested, and refined the Smart Water Dispenser.

Materials Used

XIAO ESP32 C3
TFT Screen
3d printed water drain (designed with fusion)
Jumper wires
Male to Female end wires
Button
Duct Tape
3V Motor
Water pump
3.00mm Medium Wood
LCD 16x2 I2C
Submersible pump
3D printed nozzle mount + holder

Step 1: Sketch & Planning

Defined goals: I made my first general sketches of my project on a white piece of paper with a pen and ruler. I divided my water dispenser into 2 parts: 1) The drainer box - When user in case continues to dispense water without a cup/bottle, the water will flow into the draining box instead of spilling everywhere. I also searched up on Google with reasonable size dimensions for a water dispenser.

Step 2: Sketch & Planning

Defined goals: automate hydration, safe volume control, and simple UX. Sketched system logic and listed required hardware components.

Step 2: Electronics Prototyping

Tested the pump, relay, ultrasonic sensor, buzzer, and LCD on a breadboard. Verified safe voltage levels and stable component behavior.

Step 3: Arduino Code

Used millis() for timing, pulseIn() for distance sensing, and created modular functions for scheduling, safety, and feedback.

Step 4: CAD & 3D Printing

Designed and printed a nozzle mount and bottle holder in Fusion 360. Parts were tested and iterated for stability, spacing, and waterproofing.

Step 5: Final Assembly & Testing

Components soldered on perfboard, secured inside the printed shell. Calibrated ultrasonic readings and pump timing (~200ml). Debugged button debounce and edge cases.