Skip to content

Distance Sensor

On this page we will learn

  • how to connect the Distance Sensor
  • how to measure the distance to an object

Terminology

  • distance sensor – a sensor that measures how far away an object is.
  • laser – a narrow, focused beam of light; the Distance Sensor uses an invisible one to measure distance.

The PiicoDev Distance Sensor (VL53L1X) uses a laser to measure the distance to an object, up to 4 metres away.

Possible uses:

  • object detection for robots
  • parking sensors
  • measuring tapes
  • gesture and proximity controls

Connect it

  1. Connect the sensor to the PiicoDev adapter with a PiicoDev cable. See Using PiicoDev.
  2. Upload these files to the micro:bit with main.py:
    • PiicoDev_Unified.py
    • PiicoDev_VL53L1X.py

Warning

The sensor uses an invisible laser. Don't look into the sensor window.

Set it up

1
2
3
4
from microbit import *
from PiicoDev_VL53L1X import PiicoDev_VL53L1X

sensor = PiicoDev_VL53L1X()

Methods

Method Parameters Returns Description
sensor.read() none int (mm) Distance to the nearest object, up to 4000 mm

read()

Returns the distance to the nearest object in millimetres.

 1
 2
 3
 4
 5
 6
 7
 8
 9
10
from microbit import *
from PiicoDev_VL53L1X import PiicoDev_VL53L1X

# Setup
sensor = PiicoDev_VL53L1X()

# Main loop
while True:
    print(sensor.read())
    sleep(100)

PRIMM

  1. Predict what you think will happen. Be specific.
  2. Run the program.
  3. Time to investigate the code. What does each line do?
Code explanation
  • line 1 → imports all the commands from the microbit library.
  • line 2 → imports the Distance Sensor driver.
  • line 5 → creates the sensor and calls it sensor.
  • line 8 → starts an endless loop.
  • line 9 → measures the distance in millimetres and prints it in the Shell.
  • line 10 → waits 100 milliseconds before the loop repeats.

Documentation

Documentation is the official guide written by the people who made the code library, and we can use it to look up every method and its parameters, including ones that aren't covered on this page.

Exercises

PRIMM

Time to modify the code and see what happens.

Starter files are in the distance folder of your tutorial files. Solutions are on the Exercise Solutions page.

Exercise 1

Starter: distance/ex1_button_reading

Can you make the micro:bit show the distance when button A is pressed?