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A Fleet of Data in U.S. Vehicles

This article was published in Scientific American’s former blog network and reflects the views of the author, not necessarily those of Scientific American


By: Melissa C. Lott and Ian Kalin, Presidential Innovation Fellow, U.S. Department of Energy

In the early 1970s, auto manufacturers faced the challenge of how to ensure compliance with new U.S. emissions standards without sacrificing vehicle performance. As a result, they largely turned to electronically controlled fuel feed and ignition systems. And, with the addition of “On-Board Diagnostics,” a new river of digital information began to flow through the nation’s vehicles.

When first introduced, On-Board Diagnostics (OBD) systems were governed by few standards. Sensors measured engine performance and then automakers used these data to create digital controls that automatically adjust vehicle sub-systems in order to provide required pollution control. The information gathered by the sensors was also used for some basic diagnostic purposes. But, a lack of universal standards led to varying system specifications between vehicle manufacturers, inhibiting widespread use of these data.


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In 1988, in response to this disjointed approach, the Society of Automotive Engineers (SAE) recommended a standard connector plug and set of diagnostic test signals. The U.S. Environmental Protection Agency adapted most of the standards from SAE for On-Board Diagnostic systems. Eight years later, a set of expanded standards and practices was adopted by the EPA and California Air Resources Board and dubbed “OBD-II.”

All cars built in the U.S. since 1996 have an OBD-II port, which gives the vehicle owner - and their mechanic - access to information on the health and operation of key systems throughout the vehicle’s controller area network. The data port (see photo) can transmit both proprietary manufacturer data and open data.

The confidential information streams include data on systems like anti-lock brakes and the air bags, which are valuable for manufacturers to monitor real-world system performance. The open data streams are required to contain information critical to diagnosing emissions-related issues but manufacturers also include additional, valuable information. Some typical parameters would include the following (varying slightly by vehicle make): ignition status (on/off), engine speed, vehicle speed, fuel level, fuel consumed since restart, odometer reading, distance covered since restart, longitude and latitude, fuel efficiency, condition based maintenance, brake pedal status (on/off), headlamp status (on/off), high beam status (on/off), windshield wiper status (on/off), ABS status (on/off), accelerator pedal position, torque at transmission, parking brake status (on/off), door open status (open/closed), steering wheel angle, transmission gear, and vehicle emissions status.

The raw data is simply a digital stream (bunch of 1’s and 0’s) that needs to be converted from something the computer understands to something a human can read for it to be useful. One example would be the Ford OpenXC system, a new open hardware and open software platform that supports public technology innovation, which displays, the raw dataas a long text file of acronyms and readings (see examples, below). And, for the majority of vehicles, these data are not being stored in a live manner by any commercial web technology cloud service. The local data storage is minimal and primarily used for emissions testing. This leaves a wealth of valuable information literally sitting – underutilized - in individual vehicles.

Of course, other digital data streams currently exist within vehicles and are increasingly being utilized by innovators. For example, over the past decade, navigation systems have adapted to new technologies including mobile phones. Today, nearly all smart phones have some type of navigation mobile app, which travels with the vehicle owner (and, in turn, with the vehicle). Other digital systems are pushing cars to perform more laptop-like actions, such as Entune from Toyota and Sync from Ford. One can see the slow evolution of the business models for connecting these vehicle data streams and product platforms..

The addition of On-Board Diagnostics to the U.S. vehicle fleet was catalyzed by federal environmental regulations. With it, a new river of data began to flow. As a result of this data stream, a world of new possibilities was introduced for innovators and entrepreneurs who can see the opportunity that exists.

Photo Credit:

1. Photo of OBD-II port in dashboard by KlausNahr and used under this Creative Commons license.

2. Screen captures of data streams from Wikimedia Commons.