HC-SR04 – Ultrasonic Sensor Module
The HC-SR04 ultrasonic sensor uses sonar to determine the distance to an object like bats do. It offers excellent non-contact range detection with high accuracy and stable readings in an easy-to-use package. It comes complete with ultrasonic transmitter and receiver modules. (Find a wide range of sensors at solicstores.in)
The sensor has 2 openings on its front; one transmits an ultrasonic wave (transmitter) and the other receives the returning signal (receiver).
The HC-SR04 Ultrasonic sensor is an ultrasonic transducer that comes with a 4 pin interface named Vcc, Trigger, Echo, and Ground. The Trigger and the Echo pins are the I/O pins of this module and hence they can be connected to the I/O pins of the microcontroller/Arduino. The transmitter (trig pin) sends a high-frequency signal and when the signal detects an object the receiver detects the reflected waves and the Echo pin goes high for a particular amount of time which will be equal to the time taken for the wave to return back to the sensor.
The time between the transmission and reception of the signal allows us to calculate the distance to an object. This is possible because we know the sound’s velocity in the air.
This Ultrasonic sensor module is a transmitter, a receiver and a control circuit in one single pack. It has a very handy and compact construction. It offers excellent range accuracy and stable readings in an easy-to-use package. Its operation is not affected by sunlight or black material like sharp rangefinders. (although acoustically soft materials like cloth can be difficult to detect).
|Pin Number||Pin Name||Description|
|1||Vcc||The Vcc pin powers the sensor, typically with +5V|
|2||Trigger||Trigger pin is an input pin. This pin has to be kept high for 10us to initialize measurement by sending US wave.|
|3||Echo||The echo pin is an output pin. This pin goes high for a period of time which will be equal to the time taken for the US wave to return back to the sensor.|
|4||Ground||This pin is connected to the Ground of the system.|
- Operating voltage: +5V
- Theoretical Measuring Distance: 2cm to 450cm
- Practical Measuring Distance: 2cm to 80cm
- Accuracy: 3mm
- Measuring angle covered: <15°
- Operating Current: <15mA
- Operating Frequency: 40Hz
- Used to avoid and detect obstacles with robots like biped robot, obstacle avoider robot, pathfinding robot, etc.
- Used to measure the distance within a wide range of 2cm to 400cm
- Can be used to map the objects surrounding the sensor by rotating it
- Depth of certain places like wells, pits, etc can be measured since the waves can penetrate through the water
1 x HC-SR04-Ultrasonic sensor