Ultrasound transducers for measuring distance
Ultrasounds transducers for measuring distances are commonly used in robotics, automotive parking sonars. Ultrasound distance measuring is non -contact measuring method – radiation and reception of ultrasound waves. Ultrasound waves are mechanical acoustic waves with frequencies more than 20kHz. Normally humans cannot hear frequencies above 20kHz, while some animals can. For instance, bats use ultrasound location of objects. Dolphins communicate with each other using ultrasound signals. Ultrasound interacts with a hard body, and part of incoming wave energy is reflected; in other words – it is backscattered. So direct wave towards an object is backscattered widely – up to 180°. If the object is moving – the received frequency differs because of the Doppler effect. Let’s say simple example – parking sonar. Distance to object can be calculated very simply by the formula: