2.2.5 IR Obstacle Avoidance Sensor

Introduction

In this project, we will learn IR obstacle avoidance module, which is a sensor module that can be used to detect obstacles at short distances, with small interference, easy to assemble, easy to use, etc. It can be widely used in robot obstacle avoidance, obstacle avoidance trolley, assembly line counting, etc.

Required Components

In this project, we need the following components.

It’s definitely convenient to buy a whole kit, here’s the link:

Name	ITEMS IN THIS KIT	LINK
Raphael Kit	337	Raphael Kit

You can also buy them separately from the links below.

COMPONENT INTRODUCTION	PURCHASE LINK
GPIO Extension Board	BUY
Breadboard	BUY
Jumper Wires	BUY
Obstacle Avoidance Module	BUY

Schematic Diagram

Experimental Procedures

Step 1: Build the circuit

Step 2: Go to the folder of the code.

cd ~/raphael-kit/nodejs/

Step 3: Run the code.

sudo node ir_obstacle.js

After the code runs, when you put your hand in front of the module’s probe, the output indicator on the module lights up and the “Detected Barrier!” will be repeatedly printed on the screen until the your hand is removed.

Code

const Gpio = require('pigpio').Gpio;

const ir_ob = new Gpio(17, {
   mode: Gpio.INPUT,
   pullUpDown: Gpio.PUD_DOWN,
   edge: Gpio.FALLING_EDGE
});

ir_ob.on('interrupt', () => {
   console.log('Detected Barrier!');
});

Code Explanation

const Gpio = require('pigpio').Gpio;

const ir_ob = new Gpio(17, {
   mode: Gpio.INPUT,
   pullUpDown: Gpio.PUD_DOWN,
   edge: Gpio.FALLING_EDGE
});

Import the pigpio module, create an object to control the IO port Gpio17, Set it to input mode and interrupt on falling edge.

ir_ob.on('interrupt', () => {
   console.log('Detected Barrier!');
});

When an interrupt is triggered, meaning an obstacle is detected, print “Detected Barrier!”.

Phenomenon Picture