This article is the fifth in a series on Internet of Things (IoT) sensors. It teaches you about various sensors available and how to read data from them.

Hardware

  • Arduino Uno
  • Proximity Detection Sensor
  • Jumper Cables

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Software

Circuit

Step 1: Make sure your Arduino is not connected to a power source.

Step 2: Using jumper cables connect power (VNC) and ground (GND) ports on Arduino to power (+) and ground (-) ports on breadboard.

Tip: It is a good practice to use red jumper cable for power (+ / VNC) and black jumper cable for ground (- / GND).

Step 3: Now that your breadboard has a power source, using jumper cables connect power (+) and ground (-) ports of your breadboard to power and ground ports of the Proximity Detection sensor.

Step 4: To trigger a burst connect a jumper cable from TRIG pin of the sensor to D2 (Digital) port of Arduino.

Step 5: To read echo connect a jumper cable from ECHO pin of the sensor to D3 (Digital) port of Arduino.

Your circuit is now complete and it should look similar to figures below.

CodifyThings - Internet of Things (IoT) Sensors

Arduino Code

Next you are going to write Arduino code that will read sensor data. Start your Arduino IDE and either type the code provided below or download it from GitHub. All the code goes into a single source file (*.ino) but in order to make it easy to understand and reuse, it has been divided into 3 sections.

  • External Libraries: includes all libraries required to run the program
  • Sensor Setup: code for reading sensor data
  • Standard Arduino Functions: implementation of standard Arduino functions setup() and loop()
/***************************************************************************
* External Libraries
**************************************************************************/

#include <SPI.h>

/*****************************************************************************
* Sensor Setup - Variables & Functions
****************************************************************************/

int calibrationTime = 30;
#define TRIGPIN 2 // Pin to send trigger pulse
#define ECHOPIN 3 // Pin to receive echo pulse

void calibrateSensor()
{
//Give sensor some time to calibrate
Serial.println("[INFO] Calibrating Sensor ");

for(int i = 0; i < calibrationTime; i++)
{
Serial.print(".");
delay(1000);
}

Serial.println("");
Serial.println("[INFO] Calibration Complete");
Serial.println("[INFO] Sensor Active");

delay(50);
}

void readSensorData()
{
// Generating a burst to check for objects
digitalWrite(TRIGPIN, LOW);
delayMicroseconds(10);
digitalWrite(TRIGPIN, HIGH);
delayMicroseconds(10);
digitalWrite(TRIGPIN, LOW);

// Distance Calculation
float distance = pulseIn(ECHOPIN, HIGH);

Serial.println("[INFO] Object Distance: " + String(distance));
}

/***************************************************************************
* Standard Arduino Functions - setup(), loop()
**************************************************************************/

void setup()
{
// Initialize serial port
Serial.begin(9600);

// Set pin mode
pinMode(ECHOPIN, INPUT);
pinMode(TRIGPIN, OUTPUT);

// Calibrate sensor
calibrateSensor();
}

void loop()
{
// Read sensor data
readSensorData();

// Delay
delay(5000);
}

Final Product

Make sure your Arduino is powered on and code from above has been deployed. As soon as code has been deployed, open serial monitor.

CodifyThings - Internet of Things (IoT) Sensors