# Case 09: Control the Car with an Indicator ## Purpose Build a car with the bricks and control it with the AI Lens via the indicators. ![](./images/05035_01.png) ## Products Link [ELECFREAKS Smart AI Lens Kit](https://shop.elecfreaks.com/products/elecfreaks-smart-ai-lens-kit?_pos=1&_sid=d572dc26c&_ss=r) [ELECFREAKS Nezha Breakout Board](https://shop.elecfreaks.com/products/elecfreaks-nezha-breakout-board?_pos=1&_sid=327dd9f18&_ss=r) [ELECFREAKS High-Speed Building Blocks Motor](https://shop.elecfreaks.com/products/elecfreaks-high-speed-building-blocks-motor?_pos=4&_sid=1012c2d84&_ss=r) ### Materials Required and Connection Diagram Connect the AI Lens to the IIC port and the two motors on M1,M4 ports on the Nezha expansion board as the picture shows. ![](./images/05035_09_01.png) Build a car with the bricks below. ![](./images/05035_07_01.png) ![](./images/05035_09_02.png) ![](./images/05035_09_03.png) ![](./images/05035_09_04.png) ![](./images/05035_09_05.png) ## MakeCode Programming ### Step 1 Click "Advanced" in the MakeCode drawer to see more choices. ![](./images/05001_04.png) We need to add a package for programming. Click "Extensions" in the bottom of the drawer and search with "PlanetX" in the dialogue box to download it. ![](./images/05001_05.png) Then search with “nezha” to download this extension. ![](./images/05035_09_06.png) ***Note:*** If you met a tip indicating that the codebase will be deleted due to incompatibility, you may continue as the tips say or build a new project in the menu. ### Step 2 ### Code as below: Initialize the AI lens while on start and switch its function to Card recognition. ![](./images/05035_09_07.png) Get one image from the AI Lens, if the card is detected, judge the distance from the card to the car. If it is a long distance, the lens would get the value of the “X-axis”and respond it by adjusting the speed of the two motors to keep the image in the middle of the lens. ![](./images/05035_09_08.png) If the car is near to the card, judge the instructions(symbols) on the card. If it is a turn-right instruction, make the car turn right by adjusting the speed of the motors, then program to get 3 images from the lens and give no instruction to these three pictures to clear the caches. If it is a stop instruction, make the car stop moving by adjusting the speed of the motors, then program to get 3 images from the lens and give no instruction to these three pictures to clear the caches. ![](./images/05035_09_09.png) If the AI Lens does not detect any image, the car moves forward. ![](./images/05035_09_10.png) Completed Code: ![](./images/05035_09_11.png) ### Link Link:[https://makecode.microbit.org/_09hHUgWMeY2o](https://makecode.microbit.org/_09hHUgWMeY2o) You may also download it directly below:
### Result Drive the car and make it move with the instructions.