The main aim of this project is to develop an IoT-based home automation system for controlling electrical appliances wirelessly using a NodeMCU module and Blynk application. The Blynk app installed on an Android smartphone acts as a remote control, allowing the user to switch connected appliances ON or OFF through the Internet. The NodeMCU receives commands through its built-in Wi-Fi and controls the appliances using relay modules. The proposed system is powered by a solar panel, which charges a rechargeable battery through a charging circuit. A boost converter is used to increase the DC voltage when required. The stored battery power is converted into AC power using an inverter, which can supply AC loads such as a bulb and a three-pin socket. A CPU fan is also connected to the NodeMCU through a relay and can be controlled remotely using the Blynk application. An HC-SR04 ultrasonic sensor is used for automatic object detection. The sensor is interfaced with the Arduino/NodeMCU-based control system, and its status is displayed on the Blynk application. Based on the ultrasonic sensor input, one selected appliance can be switched ON or OFF automatically. The system provides convenient wireless control, reduces unnecessary energy consumption, and makes use of solar energy as a renewable power source.        

The objectives of the project include:  

  To develop an IoT-based home automation system using NodeMCU.

  To control electrical appliances remotely through the Blynk mobile application.

  To use relay modules for wireless ON/OFF control of appliances.

  To use a solar panel and rechargeable battery as the power source.

  To use a boost converter for increasing the required DC voltage.

  To convert battery DC power into AC power using an inverter.

  To detect objects using an HC-SR04 ultrasonic sensor.

  To automatically control one appliance based on ultrasonic sensor detection.

  To display sensor and appliance status through the Blynk application.

  To reduce power wastage and provide a convenient smart-home control system.        

The main building blocks of the project are:  

• Adapter Power Supply.
• NodeMCU.
• Arduino UNO.
• LM2596 regulator.
• 4 Relay Bord.
• 4 Appliances.
• Inverter.
• Solar.
• Charging Circuits.
• Step Down Transformer.
• Boost Converter.
• Rechargeable Battery.
• Three Pin Socket.
• CPU Fan.
• AC Bulb.

             

Software’s used:  

1. Arduino ide studio compiler to write the program.
2. Express SCH for Circuit design.
3. Blynk APP.

               

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