Published January 29, 2017 © CC BY

Measuring Presence of a Car

The presence of a car can be measured by changes in the magnetic field. We are using the magnetometer to build a tiny parking sensor.

BeginnerWork in progress1 hour2,649

Things used in this project

Hardware components

Calliope mini

BBC micro:bit board

Story

In this project, I tried to use a Calliope Mini and a micro:bit to measure the changes in magnetic field strength in order to detect the presence of a car in a parking lot. The micro:bit has to be put under the car, and another micro:bit or Calliope Mini will receive the measurements. In a later version, a real detection algorithm will be applied so that the receiving board can show "in use" vs. "available" signs.

parking sensor

let Platzhalter = 0
radio.onDataPacketReceived(({receivedNumber}) => {
    basic.showString("r:")
    basic.showNumber(receivedNumber)
})
input.onButtonPressed(Button.A, () => {
    for (let i = 0; i < 100; i++) {
        Platzhalter = input.magneticForce(
            Dimension.Strength
        )
        radio.sendNumber(Platzhalter)
        basic.showString("s:")
        basic.showNumber(Platzhalter)
        basic.pause(2000)
    }
})