4. Case 03: Automatic Gate

4.1. Introduction

To make an automatic gate with the ultrasonic sound sensor controlled by the micro:bit.

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4.2. Quick Start


Materials Required


Nezha expansion board × 1

micro:bit × 1

360° servo × 1

Sonar:bit × 1

RJ11 wire × 1

Bricks details

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Connection Diagram


  • Connect the 360° servo to S1 and the ultrasonic sound sensor to J1 on the Nezha expansion board as the picture shows.

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Assembly


Build a device as the picture shows:

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Video reference: https://youtu.be/nOh7YCmcotA

4.3. MakeCode Programming


Step 1

Click “Advanced” in the MakeCode to see more choices.

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For programming, we need to add a package: click “Extensions” at the bottom of the MakeCode drawer and search with “PlanetX” in the dialogue box to download it.

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For programming, we need to add a package: click “Extensions” at the bottom of the MakeCode drawer and search with “nezha” in the dialogue box to download it.

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Notice: If you met a tip indicating that some codebases would be deleted due to incompatibility, you may continue as the tips say or create a new project in the menu.

Step 2

Code as below:

../../_images/case_03_10.png

Reference

Link:https://makecode.microbit.org/_VqieaTVyeUXx

You may also download it directly below:

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Result

  • While the ultrasonic sound sensor detects any object, the gate opens automatically.