4. Case 03: Automatic Gate#

4.1. Introduction#

A simple automatic sensor door. When the ultrasonic sensor detects that a person is approaching, the micro:bit controls the servo to automatically open the door. When no person is approaching, the micro:bit controls the servo to automatically close the door.

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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 Tips: You may need to purchase Nezha Inventor’s Kit if you want all the above compoents.

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 Video#

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

Assembly Steps#

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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:#

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Reference#

Link:https://makecode.microbit.org/_MssY8AXgCbkK

You may also download it directly below:

Result#

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

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