Project Hub /Audio Displays & Interactive Media/LED Matrix & Cube Displays/Smart Phone Controlled Arduino Mood Light with Alarm

Intermediate

ARDUINO

₹500 – ₹1,500

3 – 6 Hours

Partial Kit

Smart Phone Controlled Arduino Mood Light with Alarm

Build a smartphone-controlled Arduino mood light and alarm system utilizing NeoPixel LEDs and chromotherapy principles.

Originally published on CircuitDigest

View original tutorial

Parts You'll Need

This project is sourced from another site, not written by us — this list is our best match of their components against what we stock, not a verified bill of materials. Always check the original blog (linked above) for the actual parts list before buying.

ESP32 WiFi+Bluetooth CP2102 Development Board Rs. 520.00
LDR Light Sensor Module Rs. 49.00
10pcs - 220 ohm 1/4 W Resistor Set Rs. 39.00
MB102 Adjustable Breadboard Power Supply Module (3.3V & 5V) for Arduino & Raspberry Pi Rs. 139.00
400 Points Mini Solderless Prototype PCB Breadboard High Quality Rs. 89.00
Jumper Wire 10 Pin Male To Male 20cm Rs. 45.00
Jumper Wire 10 Pin Male To Female 20cm Rs. 45.00

Selected: Rs. 0.00

This list includes a generic resistor set as a placeholder — it is not matched to the exact value or part number this circuit needs. The correct one is specified on the original source page linked above; check it before buying.

We don't carry yet: Arduino (unspecified board)
LED Strip / NeoPixel / WS2812
RTC Module DS3231 / DS1307
Enclosure / Box / Case

Browse all components

How It Works

The Smart Phone Controlled Arduino Mood Light and Alarm system operates by integrating multiple hardware modules controlled centrally by an Arduino Pro Mini. Power is supplied via a 12V power supply connected to the board's RAW pin, which uses an onboard voltage regulator to step down the voltage safely. Timekeeping is managed by the DS3231 RTC module communicating via I2C, ensuring accurate scheduling for the alarm feature. Users interact with the system wirelessly through an HC-05 Bluetooth module, which pairs with a smartphone to send serial commands processed by the Arduino using the SoftwareSerial library. An LDR combined with a 100K resistor acts as a voltage divider circuit to monitor ambient light levels, allowing the system to adjust its behavior based on room brightness. Based on user inputs and sensor data, the Arduino drives NeoPixel LEDs to emit customizable colors and patterns, drawing on chromotherapy principles for relaxation and sleep-aid applications. System settings can be persistently saved using the microcontroller's internal EEPROM library, and the physical build can be housed neatly inside an optional 3D printed enclosure.

Why Build This

Design and prototype an undergraduate-level embedded system combining wireless Bluetooth control, real-time clock tracking, and custom lighting.

Implement practical chromotherapy wellness concepts using programmable NeoPixel LEDs and ambient light sensing.

Gain hands-on engineering experience in power management, serial communication protocols, and peripheral integration on a compact microcontroller platform.

Real-World Application

Smart home lighting, automated sleep-aid devices, and chromotherapy-based wellness gadgets for bedrooms and relaxation spaces.

Skills You'll Learn

Microcontroller firmware development

Bluetooth serial communication

I2C bus protocol implementation

Analog sensor interfacing with voltage dividers

Addressable LED data signal management

Non-volatile memory storage with EEPROM

Safety Precautions

Ensure correct power supply voltage (12V adapter connected to RAW pin) to prevent damage to the voltage regulator and connected modules.

Technology Tags

ARDUINO

NEOPIXEL

WS2812

BLUETOOTH

HC-05

DS3231 RTC

LDR

EEPROM

ANDROID

CHROMOTHERAPY

LIGHTING

Frequently Asked Questions

Why must the 12V power supply be connected to the RAW pin instead of the VCC pin?

The RAW pin routes voltage through the Arduino Pro Mini's onboard voltage regulator, which safely steps down 12V to the 5V or 3.3V required by the microcontroller. Connecting 12V directly to the VCC pin bypasses this regulation and will permanently damage the board and attached modules.

What is the role of the LDR and 100K resistor in this circuit?

The Light Dependent Resistor (LDR) and the 100K resistor form a voltage divider circuit. As ambient room light changes, the resistance of the LDR changes, altering the analog voltage signal read by the Arduino to gauge room brightness.

Do I need any special software libraries to make the code compile?

Yes, you will need to install the Adafruit_NeoPixel library for controlling the LEDs, the DS3231 library for the real-time clock, and use the built-in SoftwareSerial and EEPROM libraries within the Arduino IDE.

Gallery

This page is part of Kitkraft's Project Hub — a curated collection of electronics & robotics projects gathered from the maker community to help students and hobbyists discover and learn to build. Kitkraft does not claim authorship of the original project, and makes no representation as to the accuracy, completeness or safety of third-party source material. The summary and "How It Works" explanation above are AI-generated, rewritten with reference to the original tutorial — not a reproduction of it. Full credit and a direct link to the original source are provided above. If you're the original creator and have a concern about how your work is represented here, please contact us and we'll address it promptly.

Kitkraft Project Hub — curated from the maker community, credited at the source.

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