Parking sensors, also known as geomagnetic sensors. When the vehicle is parked on the road, it can warn the driver of invisible obstacles. The entire system is also sometimes referred to as the vehicle distance alarm (PDC).
Parking sensors generally fall into two categories
Electromagnetic parking sensor
The electromagnetic parking sensor relies on the vehicle moving slowly and smoothly toward the subject. Once an obstacle is detected, the vehicle is temporarily stopped and the sensor will get a signal that the obstacle is present. Electromagnetic parking sensors provide a unique design that is discretely mounted on the inside of the bumper.
Ultrasound reversing sensor
At present, ultrasonic sensors can be seen in several brands of cars, and various brands such as PARKTRONIC parking aids. Some systems also provide additional upgrade packages that will be installed later.