The hc-sr04 Ultrasonic Sensor Arduino uses sonar to determine the distance to an object like bats or dolphins do. It offers excellent non-contact range detection with high accuracy and stable readings in an easy-to-use package. From 2cm to 400 cm or 1” to 13 feet. Its operation is not affected by sunlight or black material like Sharp rangefinders are (although acoustically soft materials like cloth can be difficult to detect). It comes complete with the Ultrasonic Sensor transmitter and a receiver module. This is easily interfaceable for many microcontrollers like Arduino uno r3, Microchip PIC and ST Microcontrollers.
