Smart Pet Water Dispenser

A smart device that automatically refills a pet's water bowl and monitors water temperature, providing convenience for pet owners.

info

Author: Cosac Alexia
GitHub Project Link: https://github.com/UPB-PMRust-Students/project-alexiacosac

Description

The Smart Pet Water Dispenser is an automated system designed to keep pets hydrated by refilling their water bowl whenever the level drops too low. Powered by a Raspberry Pi Pico W, it uses a water level sensor and a water pump to maintain consistent water levels without constant human intervention.

To ensure safety and usability, the system also monitors water temperature via a sensor and displays it on an LCD screen, while an RGB LED provides status indicators (green for normal, red for errors). It also features remote connectivity for monitoring and controlling the system through a simple web interface.

Smart Pet Water Dispenser Presentation

Motivation

I chose to work on this project because ensuring pets have constant access to clean water is a common challenge for many pet owners, especially during busy schedules or when away from home. As a cat owner, I have personally faced the difficulty of maintaining a reliable water supply for my pet, which motivated me to develop the Smart Pet Water Dispenser.

Architecture

The architecture components of the Smart Pet Water Dispenser:

• Sensor Data Processing Component – Responsible for receiving and processing input from the water level and temperature sensors. It continuously monitors the state of the system to provide relevant data to the control unit.

• Control Logic Component – The central decision-making unit that evaluates sensor data to trigger appropriate actions. Based on the water level and temperature readings, it decides whether to activate the water pump or signal an alert via the RGB LED.

• Actuation and Feedback Component – Manages the response of the system to control signals. It operates the water pump to refill the bowl and uses the RGB LED to provide feedback about the system’s health (e.g., red for errors, green for normal operation).

• User Interface Component – Displays real-time data, such as water temperature and system status, to the user via an OLED display. It ensures visibility into the system's current state.

• Connectivity and Remote Monitoring Component – Allows the user to monitor and control the dispenser remotely via a web interface. This module communicates with the Raspberry Pi Pico over a network to offer access to system data and control over actions such as refilling the water remotely.

Log

Week 5 - 11 May

This week, I was able to have all the components required for my project. I soldered both Raspberry Pi Picos and connected them on the breadboard using probedebug. I also tested them with a short code to check that everything works fine.

Week 12 - 18 May

I connected and tested several components of the project. The RGB LED was successfully integrated and responds correctly to control signals. I also connected the LCD display and began displaying test messages on it. I wired the temperature and water level sensors and started checking their readings through initial tests.

Week 19 - 25 May

This week I finished both software and hardware parts of my project and presented it to my laboratory professor. The final steps were implementing the water pump, the relay module and a level shifter to make my project work properly.

Week 26 - 2 June

Hardware

The hardware components include:

• Raspberry Pi Pico

  Controls the entire system and interfaces with sensors and actuators.

• ESP8266 or ESP32 (Wi-Fi Module)

  Provides Wi-Fi connectivity for remote monitoring and control.

• Water Level Sensor

  Detects when the water level drops and triggers the pump.

• Temperature Sensor (DS18B20)

  Monitors the water temperature and displays it on the OLED screen.

• Electric Water Pump (5V)

  Pumps water into the bowl when the level is low.

• Relay or MOSFET

  Switches power to the water pump safely.

• Diode

  Protects the circuit from back EMF generated by the pump.

• RGB LED

  Shows system status (green for normal, red for errors).

• OLED Display

  Displays water temperature and system status.

• 5V Power Supply

  Powers all system components.

• Breadboard and Jumper Wires

  For prototyping and connecting components.

• Tubing and Water Reservoir

  Stores and transports water to the pump.

• Resistors

  Limits current to protect components.

Schematics

Place your KiCAD schematics here.

Bill of Materials

Device	Usage	Price (RON)	Link
Raspberry Pi Pico W	Main microcontroller with Wi-Fi	39.97	Robofun
ESP8266 Wi-Fi Module	Provides Wi-Fi connectivity	19.00	Robofun
Water Level Sensor	Detects low water level	33	eMag
DS18B20 Temperature Sensor	Monitors water temperature	9.62	Robofun
Electric Water Pump 5V	Pumps water into the bowl	13.49	eMAG
Relay Module 5V	Controls power to the water pump	12.00	Robofun
1N4007 Diode	Protects circuit from back EMF	0.25	Vendigo
RGB LED	Status indication (green, red)	11.4	Robofun
OLED Display 0.96"	Displays water temperature and system status	35	eMag
5V Power Supply	Powers the entire system	12.00	Robofun
Jumper Wires	Connecting components on breadboard	2.6	Robofun
Silicone Tubing 1m	Transports water from reservoir to bowl	9.00	Iazuri Acvarii

Software

Library	Description	Usage
rp2040-hal	Controls GPIOs, timers, and PWM	Used for controlling sensors and the water pump
embedded-hal	Standard interface for external devices	Used for hardware abstraction
panic-halt	Stops the program on critical errors	Used for error handling
embassy	Manages asynchronous tasks	Used for task management
ds18b20	Reads temperature from DS18B20	Used for reading water temperature
ssd1306	Displays information on OLED screen	Used for displaying water temperature
smart-leds	Controls the RGB LED indicator	Used for visual status indication
pwm	Controls the power level of the water pump	Used for controlling water pump speed
wifi	Manages Wi-Fi connectivity	Used for connecting to the network for remote control and monitoring
hyper	HTTP library	Used for building the web interface to monitor and control the dispenser remotely

Links

How to run a web server with Raspberry Pi Pico