43. Case 39：The Mechanical Crab

43.1. Introduction

Build a mechanical crab with the Nezha Inventor’s Kit.

43.2. Quick to Start

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Materials Required

Nezha Inventor’s Kit

Assembly

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Components List

Build it as the assembly steps suggest:

We can see that the construction is completed as shown in the following figure:

Connection Diagram

Connect the Ultrasonic Sensor to J1 and the motor to M1 on Nezha Breakout Board.

43.3. MakeCode Programming

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Step 1

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

For programming the Ultrasonic Sensor, we need to add a package. Search with “PlanetX” in the dialogue box and click to download it.

For programming Nezha Breakout Board, we need to add a package. Search with “Nezha” in the dialogue box and click to download it.

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 the picture suggests

Reference

Link: https://makecode.microbit.org/_09MCJLLdTYcr

You may also download it directly:

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Result

After powering on, if the crab sees an approaching object ahead, it will crawl towards sideways.