Ultrasonic Sensor HC-SR04

The HC-SR04 is a popular ultrasonic sensor module used for distance measurement in various projects and applications. It is commonly used with microcontrollers such as Arduino for obstacle detection, object avoidance, and distance sensing.

Here are some key features and information about the HC-SR04 ultrasonic sensor:

1. Principle of Operation: The HC-SR04 sensor module uses ultrasonic sound waves to measure distance. It consists of an ultrasonic transmitter (which emits sound waves) and an ultrasonic receiver (which detects the reflected waves). By measuring the time taken for the sound waves to travel to an object and back, the sensor can calculate the distance.
2. Distance Range: The HC-SR04 sensor module can typically measure distances from 2 cm (0.79 inches) up to around 400 cm (157.5 inches). The effective range may vary based on factors such as the environment, object surface, and sensitivity settings.
3. Measurement Accuracy: The HC-SR04 sensor can provide distance measurements with reasonable accuracy, typically within a few millimeters. However, the accuracy can be affected by factors such as temperature, humidity, and ambient noise.
4. Operation: To use the HC-SR04 sensor, you typically need to provide it with a trigger signal from a microcontroller or another digital output device. This trigger signal initiates the transmission of ultrasonic pulses. The sensor then detects the echo of the transmitted pulse and provides a corresponding output signal that can be interpreted to calculate the distance.
5. Output: The HC-SR04 sensor provides distance measurements in the form of a pulse width or a signal duration. The duration of the output signal represents the time taken for the ultrasonic waves to travel to the object and back.
6. Wiring: The HC-SR04 sensor module typically has four pins: VCC (power supply), GND (ground), Trig (trigger), and Echo (echo signal output). It requires both a 5V power supply and a separate GPIO pin to trigger the sensor and read the echo signal.