Parktronic System (PTS), also called Acoustic Parking System (APS), Park Sensor, Park Radar, Park Assist, or Park Distance Control (PDC), is a parking-assistance system installed on some Audi, Mercedes-Benz, Lexus, and BMW cars, amongst others.

Parktronic: Description

Parktronic uses ultrasonic proximity sensors embedded in the front and/or rear bumpers, to measure distance to nearby objects by timing how long it takes for sound waves to be reflected off them. The system then emits an intermittent warning tone inside the vehicle to indicate how far the car is from an obstacle. As the distance decreases, the warning tone becomes faster, allowing the motorist to judge the distance from the vehicle to the object. The system may start emitting sounds when the car is approximately 1.0, 1.2, or 1.8 metres from the obstacle, and the car operating at speeds less than 9 miles per hour (14 km/h). The tone becomes continuous when the distances closes to about 300 millimetres (12 in). In some vehicles, it may also offer visual feedback through an LCD display on the dashboard. Parktronic can be switched off for situations such as stop-and-go traffic.

Parktronic: Shortcomings

Since the system relies on the reflection of sound waves, it may not detect some items that are not flat or large enough to reflect sound, for example a narrow pole or a longitudinal object pointed directly at the vehicle.