Sensor, Park Assist: Operation

The park assist sensors are ultrasonic transceivers that are completely controlled by the Park Assist Module (PAM). The sensors transmit and receive ultrasonic signals. The sensors each receive battery current and ground in parallel from the PAM, but are each connected to individual dedicated serial bus communication circuits to the module.

Each sensor membrane is oscillated, then quieted by the PAM in a pulsating fashion. While the sensor membrane oscillates, it emits an ultrasonic signal. This signal will bounce or echo off of objects in the path of the vehicle. While quieted, each membrane receives the echoes of the ultrasonic signals it and the other sensors have transmitted. The sensors then communicate this echo data over the serial bus lines back to the PAM. The PAM uses the intervals between the ultrasonic transmission and reception data from the sensors to calculate the distance to any obstacles identified by the ultrasonic echoes.