What it shows
An ultrasonic sensor sends out a pulse of sound and times its echo to measure distance. When a hand comes close, the Arduino tells a servo motor to lift the lid.
This idea has a short entry only. For the science behind it, read the sentence above with your textbook and ask your teacher to explain the law or idea it shows, so you can describe it in your own words.
Materials
- An Arduino Uno and USB cable
- An HC-SR04 ultrasonic sensor
- An SG90 servo motor
- A small dustbin
- Jumper wires, and a USB power bank (or a 4 AA battery pack for the servo, with its ground joined to the Arduino ground)
Safety
For this project: Use USB or battery power only, never the mains directly.
Never use mains electricity: power models with cells, batteries or a low-voltage adapter. Sharp and hot tools, flames and lab chemicals need an adult or your teacher beside you. Keep magnets, button cells and small parts away from young children, and wash your hands after making.
How to go about it
Numbered steps have not been written for this idea yet. Plan it with your teacher: sketch the design with measurements, build one part at a time, test each part, and write every observation with the date. The free ebooks below have step-by-step projects of the same kind.
Free ebooks for this project
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