12. Case 11: Line-tracking Car#

12.1. Introduction#

This is a line tracking car, we can use black electrical tape to paste a track on the white plane, and then make the car drive according to the preset trajectory.

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12.2. Quick Start#

Materials Required#

Nezha expansion board × 1

micro:bit × 1

Line-tracking sensor × 1

Motors × 2

RJ11 wires × 1

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

Connection Diagram#

Connect the line-tracking sensor to J1, the two motors to M1&M4 on the Nezha expansion board as the picture shows.

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Assembly Video#

Video reference: https://youtu.be/N2w01pGaj30

Assembly Steps#

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12.3. 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_11_15.png

Reference#

Link:https://makecode.microbit.org/_MbaX4mTEmHmf

You may also download it directly below:

Result#

The car drives along with the black line.

../../_images/case-gif-11.gif