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Electronic Components
Ultrasonic Sensor
The HC-SR04 is the industry-standard ultrasonic module for beginners, providing non-contact distance measurement for robotics.
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Ultrasonic Sensor (HC-SR04)
Uses sound waves to measure distance. It emits a high-frequency sound pulse and measures the time it takes for the echo to reflect back from an object.
Key Applications
- Obstacle avoidance
- Distance measurement
- Liquid level sensing
Range: 2cm to 400cm | Angle: 15° | Supply: 5V DC🧪The Science Behind It
The Ultrasonic sensor works on the principle of Echolocation, similar to how bats and dolphins navigate. It uses a transducer to send out a high-frequency sound pulse (40kHz).
The Time of Flight (ToF) principle is used to calculate distance: The sensor triggers a pulse, waits for the echo to return, and calculates the distance based on the speed of sound (approx. 343m/s).Distance = (Time × Speed of Sound) / 2
Pin Configuration
VCC5V Power Supply
TrigTrigger input to start the sound pulse
EchoOutput pulse width corresponds to distance
GNDGround Connection