Heavy Vehicle EDRs can be categorized into four general types. The type of EDR that is the most common is the type that is part of the ECM. Therefore, this "built-in" HV EDR is the major topic of this site. However, we describe the other, less common types below.
The EDR that is an Addition to the ECM or Drivetrain
Add-on systems were more common prior to robust ECM computers. The first electronic system was the Rockwell Tripmaster in 1979. Others include Pro-Driver, which works along with the Detroit Diesel engine, and Road Relay, which works along with the Cummins engine. Tachographs are another type of add-on. Although tachographs are more common in Europe than the US, they are still seen on some new US trucks.
The EDR that is Part of Another Vehicle (Safety) System
EDRs that are part of safety systems represent cutting-edge developments in transportation safety. One is the Eaton VORAD system. VORAD is a collision avoidance system that employs directional radar(s). In the event a crash does occur, the VORAD can store a large amount of data about the seconds leading up to impact.
Another is the Bendix ABS-6 with ESP (Electronic Stability Program). This is an advanced computer-controlled braking system that may contain an EDR capability.
The EDR that is Part of a Telematics (GPS) System
Telematics is the combination of GPS and telecommunications technology to generate and store data (in this case, the data stored are about a vehicle or the load it is carrying). A telematics system is not necessarily an “EDR,” although some systems do have an EDR function built in. Products by Qualcomm, Dynafleet, PeopleNet, Cadec, and XDATA are common in commercial motor vehicles and have applications for logistics, fleet management, and homeland security. Determining if a vehicle is equipped with a telematics product may be as easy as locating the keyboard terminal in the truck cab. Determining if the telematics system has an EDR function can be much more difficult.