Smart Home and IOT Design

Overview:

Mainstream SMART home tech caters to luxury living in the developed west - not to developing nations. While Western homes get voice-controlled lights, Sri Lankans face deadly risks from substandard gas imports - like the 2021 gas canister explosion crisis that rocked households nationwide. Drawing on my own Sri Lankan roots, I embraced the challenge of developing a SMART home package for the typical Sri Lankan home.

Technical implementation:

System	Electric Components	Sensors	Actuators
Air Purification and Warning System	Arduino Microcontroller Full-bridge rectifier & Transformer (Mains voltage needs to be converted to DC and within 5V for the microcontroller) LEDs, N-Channel MOSFET	Winsen Gas Sensor	Piezo Buzzer Brushless 12V DC motor (Fan) Fans fixed with PM2.5 and TiO₂ filters

📱 Mobile users: Please use a desktop or laptop device to view the interactive Tinkercad simulation.
Or click here to open the simulation in a new tab

How it works:

Detection: NO₂, PM2.5 Particles, CH₄, CO

Filtration:

PM2.5 + TiO₂ filters remove airborne pollutants
12V brushless DC motor creates negative pressure to extract fumes

Monitoring:

Fan speed auto-regulated via analogue Winsen gas sensor
Wind speed sensor tracks airflow strength and alerts user with LED if airflow drops, indicating filter replacement
N-Channel MOSFET used for efficient switching

Warning:

Piezo buzzer activated when pollutants exceed safe levels
LED indicators provide visual alerts