INTEGRATION OF SENSOR AND ACTUATORS WITH ARDUINO in IoT

Sensors

• Basic electronic Device
• Convert a physical quantity/ measurements into electrical signals
• Can be analog or digital

Types of Sensors

Some commonly used sensors :

• Temperature
• Humidity
• Compass
• Light
• Sound
• Accelerometer

Sensor Interface with Arduino

Digital Humidity and Temperature Sensor (DHT)


PIN 1,2,3,4 (from left to right)

• PIN 1-3.3V-5V Power supply
• PIN 2- Data
• PIN 3-Null
• PIN 4- Ground

DHT Sensor Library

• Arduino supports a special library for the DHT11 and DHT22 sensors
• Provides function to read the temperature and humidity values from the data pin

           dht.readHumidity()
           dht.readTemperature()



Connection

• Connect pin 1 of the DHT to the 3.3 V supply pin in the board
• Data pin (pin 2) can be connected to any digital pin, here 12
• Connect pin 4 to the ground (GND) pin of the board

Sketch: DHT_Sensor

Install the DHT Sensor Library

• Go to sketch -> Include Library -> Manage Library

• Search for DHT Sensor
• Select the "DHT sensor library" and install it

• Connect the board to the PC
• Set the port and board type
• Verify and upload the code

OutPut

The readings are printed at a delay of 2 seconds as specified by the delay() function