LED Controlling using PIR & LDR Sensors with Raspberry Pi | Smart Lighting System | IoT Lab Project

In this experiment, we implement a smart lighting system using a Raspberry Pi, PIR sensor, and LDR sensor for controlling LED.
Experiment : Automated LED light control based on input from PIR (to detect if people are present) and LDR(ambient light level)

PIR Sensor (Passive Infrared): Detects human presence or motion.

LDR (Light Dependent Resistor): Measures the ambient light level.

Raspberry Pi: Acts as the controller to process sensor inputs and control the LED.

💡 Working Principle:

When a person enters the room and the ambient light is low, the Raspberry Pi turns the LED ON.

If no motion is detected or the room is already bright, the LED remains OFF.

This project demonstrates energy-efficient automated lighting using Raspberry Pi and sensor-based control.
It is a part of the IoT Laboratory Experiments (JNTUA syllabus) and helps students understand sensor interfacing, Python programming on Raspberry Pi, and automation logic.

🔹 Topics Covered in this Video:

PIR Sensor working & interfacing with Raspberry Pi

LDR Sensor working & interfacing with Raspberry Pi

Writing Python code for automation logic

Demonstration of LED light control experiment

👉 This experiment is highly useful for home automation, energy saving, and IoT-based smart systems.

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We are going to upload New Videos of these experiments.
List of Experiments:

1. Serial Monitor, LED, Servo Motor - Controlling
• Experiment1: Controlling actuators through Serial Monitor. Creating different led patterns and controlling them using push button switches. Controlling servo motor with the help of joystick.

2. Distance Measurement of an object
• Experiment 2: Calculate the distance to an object with the help of an ultrasonic sensor and display it on an LCD.
3. LDR Sensor, Alarm and temperature, humidity measurement
• Experiment 3:
• Controlling relay state based on ambient light levels using LDR sensor.
• Basic Burglar alarm security system with the help of PIR sensor and buzzer.
• Displaying humidity and temperature values on LCD
4. Experiments using Raspberry Pi
• Experiment 4:
• Controlling relay state based on input from IR sensors
• Interfacing stepper motor with R-Pi
• Advanced burglar alarm security system with the help of PIR sensor, buzzer and keypad. (Alarm gets disabled if correct keypad password is entered)
• Automated LED light control based on input from PIR (to detect if people are present) and LDR(ambient light level)

5. IOT Framework
• Experiment 5: Upload humidity & temperature data to ThingSpeak, periodically logging ambient light level to ThingSpeak.
• Experiment 6: Controlling LEDs, relay & buzzer using Blynk app

6. HTTP Based
• Experiment 7: Introduction to HTTP. Hosting a basic server from the ESP32 to control various digital based actuators (led, buzzer, relay) from a simple web page.
• Experiment 8: Displaying various sensor readings on a simple web page hosted on the ESP32.

7. MQTT Based
• Experiment 9: Controlling LEDs/Motors from an Android/Web app, Controlling AC Appliances from an android/web app with the help of relay.
• Experiment 10: Displaying humidity and temperature data on a web-based application

8. UAV/Drone:
• Experiment 11:
o Demonstration of UAV elements, Flight Controller
o Mission Planner flight planning design
• Experiment 12: Python program to read GPS coordinates from Flight Controller