Don't Hit That!

Besides mirrors and cameras, the truck has ultrasonic collision avoidance systems.  You have probably seen cars with round "dots" on the rear bumper.  These sensors connect to an internal device that beeps as the vehicle approaches an object. 

The technology is similar to automatic cameras that use an ultrasonic signal to calculate distance and then adjust the focus automatically.  The typical application for cars uses four sensors on the rear bumper.  Each sensor has an effective coverage area two feet wide and six feet deep.  The control unit interprets the sensor inputs and beeps.  The closer an object the more frequent the beeps.  Most of the systems you see on the street are aftermarket installations of EchoMaster Systems.

The same components, rebranded, are sold directly to the public through a website, CarFancy.com and via Pep Boys retail chain.  The systems are not available through Pep Boys' website.

Our installation monitors the traditional rear bumper as well as the body's top, front and rear.  The bumper has four sensors, evenly space across its width.  The top of the body has two sensors on the front and two on the rear, mounted close to the outside edges, based on the assumption that obstacles are more likely to be encountered while turning, or if presented evenly across the front or rear, the sensors would pick them up.  This design does leave a "dead spot" in the center of the top edges.

The control units allow connection of four sensors, hence the use of two control units.  The system is typically powered by the backup light lead, which makes sense for exclusive use while backing up.  Our bumper installation is configured this way.  The rooftop system is powered continuously.  It is unlikely it will generate false alarms by anyone walking by.