How to Use Line Tracking Sensor with Micro:bit?

Overview
 

When doing DIY experiments, you perhaps see such a smart car that can follow a black line and not beyond the black area. How can achieve this? Yeah, make use of line tracking sensors. In this project, we will use a tracking sensor combined with micro:bit to detect an object or a black line. You can get the result shown on the LED display of micro:bit.

Component Required:
 

• Micro:bit main board*1

• Keyestudio Micro bit Sensor V2 Shield*1

• USB Cable*1

• keyestudio Line Tracking Sensor*1

• DuPont jumper wire*3

• Premium Battery Holder 6-cell AA*1

• 1.5V AA Battery*6

Component Introduction
 

Line Tracking Sensor:
 

The tracking sensor is actually an infrared sensor, which can detect a black line. The component used in the sensor is TCRT5000 infrared tube.

Its working principle is to use the different reflectivity of infrared light to the color, then convert the strength of the reflected signal into a current signal.

When sensor detects a black line, the infrared rays are not emitted or the intensity of emitted ray back are not sufficiently strong, so that the sensor’s signal terminal outputs a High level. Otherwise, output a Low level.

In this way, we can judge the detected color by High or Low level of the sensor’s signal terminal.

Note: on the module, you can rotate the potentiometer to make the LED between on and off state. The sensitivity is the best.
 

Connection Diagram
 

Test Code
 

Test Results
 

Done wiring and powered up, send the code to micro:bit. When sensor detects no object or detects a black line, the infrared rays are not emitted or the intensity of emitted ray back are not sufficiently strong, so that the sensor’s signal terminal will output a High level, LED on the micro:bit will show the number 1. Or else show the number 0.

Note: rotate the potentiometer on the sensor, the sensitivity is highest when make the LED on and off state. The detection height is 0—3 cm.