Summary of Project X – Smart home control using Arduino
This project, "Project X – Smart home control using Arduino," automates home appliances based on room occupancy and temperature. It uses LDR sensors and light sources at the door to detect people entering or exiting, adjusting appliance states accordingly. The Arduino reads temperature via an LM35 sensor, turning on a fan if the room gets too warm. Additionally, manual control is possible using an IR remote, allowing users to operate lights, fans, or other devices without physical switches.
Parts used in the Project X – Smart home control using Arduino:
- Arduino Uno
- IR receiver
- LM35 Temperature Sensor
- 3-relay module
- 3 NPN Transistors
- 2 Light Dependent Resistors (LRD) 10k ohm
- 2 Light Sources for LDR (Laser Diodes recommended)
- Wires
- IR Remote from LED strip controller
WHAT IT DOES?:
- Turn the required appliances on/off as soon as someone enters the room(Even for multiple people)
- If there is a person inside the room and the temperature inside room rises above threshold temperature (Predefined temperature or can be changed during operation) the fan turns on.
- If you want to manually turn lights/fan/any other device on/off but right from where you are without reaching the switch board you can do that with the small IR remote controller.
THINGS USED:
- Arduino Uno
- IR receiver
- Lm35 Temperature Sensor
- 3-relay
- 3-npn Transistor
- 2 – LRD 10k ohm(Light Dependent Resistor)
- 2 Light Source For LDR (Laser Diodes recommended)
- Wires
- IR Remote From LED strip controller
TOOLS REQUIRED:
- Soldering Iron
- Hot Glue gun
WORKING PRINCIPLE:
For this smart home control mount two LDR’s on the door frame of the room on one side at somewhat 120cm above floor and on the other side of the door frame light source is mounted at the same height as the ldr.
So when the person enter the room the values of resistance of first ldr changes, then of second ldr, after that value of first value revert back and second ldr follows. These series of values are interpreted by Arduino and this cycle means a person has entered room. While exiting room this cycle happens but in opposite order. This is how arduino gets how many people are there in the room.
Arduino continuously takes temperature reading from lm35 and turns fan on once temperature rise above set temp.
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