Let’s look at parking sensors as an example. Parking sensors use a type of sonar. The term sonar is an acronym for sound navigation and radar; it’s used for calculating the distance and/or direction of an object from the time it takes for a sound wave to travel to the target and back. An ultrasonic sensor is a speaker or microphone that emits or receives ultrasound. There is also a type that can handle both emission and reception. Vehicle parking sensors are equipped with this type of sensor.
Ultrasound sensors initially found use in vehicles for detecting obstacles when parking (Figure 1) but it is now evolving into an automatic parking system.