Object Detection Description and Operation (UD7 with Display): Notes

The parking assist system is designed to identify and notify the driver of an object in the vehicle's path when reversing at speeds less than 8 km/h (5 mph). The distance and location of the object is determined by four object alarm sensors located in the rear bumper. The parking assist system will notify the driver using the rear parking assist display and an audible signal through the chime master.

The parking assist system is made up of the following components:

• Rear object sensor control module
• Object alarm sensors
• Rear parking assist display

Rear Object Sensor Control Module 

The rear object sensor control module provides an 8-volt reference and a low reference to the four object alarm sensors. The rear object sensor control module receives individual signals from each of the four sensors and determines the location and distance of an object based on these inputs. When an object is detected, the rear object sensor control module will illuminate the appropriate LED on the rear parking assist display and send a serial data message requesting an audible alert.

Object Alarm Sensor 

The object alarm sensors are located in the rear bumper of the vehicle. The sensors are used to determine the distance between an object and the rear bumper. Each sensor emits an ultrasonic frequency which is reflected off an object located behind the vehicle. These reflections are received by the sensors. The time difference between when the frequency was emitted and when the reflection is received, known as sensor echo, is used to determine the distance to the object. The sensors report this information to the rear object sensor control module.

Rear Parking Assist Display 

The rear parking assist display is located in the interior rear of the vehicle and is visible through the inside rearview mirror. The display contains three LEDs: two amber and one red. The rear object sensor control module controls these three LEDs as a visual indicator of how close the vehicle bumper is to an object. The rear object sensor control module supplies voltage to each of the LEDs and commands each LED on by supplying an individual ground.