What is Ultrasonic Sensor HC-SR04?
An ultrasonic sensor is used to measure the distance to an object using sound waves. It provides measurements of the time that takes the sound to fling something and return it to the sensor.
It works on sound wave frequency like sonar. They also cannot detect some objects.
HC-SR04 ultrasonic can measure a range of 2 cm to 400 cm (4 m).
This sensor has 2 openings on its front. One is the transmitter which transmits ultrasonic waves like a speaker and the other is a receiver that receives them like a microphone.
Mainly there operations are not affected by sunlight or black material, but acoustically, soft materials like cloth can be difficult to detect.
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Hardware Connections
- Vcc to 5V of Arduino.
- GND to GND of Arduino.
- Trig to digital pin 13 of Arduino.
- Echo to digital pin 12 of Arduino.
HC-SR04 Specifications
Board Size | 43 x 20 x 15 mm |
Working voltage | 5V DC |
Operating voltage | 5V DC |
Working Frequency | 40Hz |
Range | 2 cm to 400 cm (4 m) |
Measuring Angle | 15 degree |
Trigger Input Signal | 10 μs TTL pulse |
Echo Output Signal | Input TTL lever signal and the range in proportion |
Uses of Ultrasonic Sensor
- For Measuring Distance.
- Robotic sensing.
- Vehicle detection for car wash and automotive assembly.
- Use in Parking Areas.
- Presence detection.