Arduino distance meter with Ultrasonic Sensor (HC SR04) and Nokia 5110 LCD display
Measuring distance is so important in today’s world that things like driverless cars will be impossible without it, that description is probably enough to describe how important knowing the distance between two objects can be. For that reason, today we will be building a distance meter using the Arduino and the HC-SR04 ultrasonic sensor.
The HC-SR04 ultrasonic sensor is a cheap ranging sensor capable of measuring a distance between 20 – 400cm without contact and at an accuracy of up to 3mm. The sensor is made up of a transmitter and receiver with operating frequency of around 40khz. It uses the echo principle for distance measurement by emitting an ultrasonic wave of 40khz. If there is an object in its path, the emitted wave is reflected and the reflected signal is received via the receiver. The time elapsed between the transmission of the signal and the reception of the echo is then used to determine the distance between the sensor and an object in its path.
Arduino distance meter with Ultrasonic Sensor (HC SR04) and Nokia 5110 LCD display – [Link]