Overview

In the preceding chapters, we covered lateral, longitudinal, and integrated systems. What can be accomplished, however, if the vehicles cooperate with each other and the highway as an integrated system? What if information concerning traffic ahead, obstacles, and road and weather conditions were flowing as freely between electronic subsystems on the vehicle as do land-side computers accessing the Internet? This is the fundamental premise for CVHS, which open the way for a federated computing approach to road-vehicle systems. Some applications, such as intersection collision avoidance, work better with CVHS, and others such as traffic flow enhancement are not possible at all without cooperation.

In fact, as the information horizon extends via the use of cooperative systems, the need for emergency braking is greatly reduced, as the surprise factor diminishes. So, tongue in cheek, one could even say that the aim of cooperative systems is to put crash avoidance systems out of business!

The prospect of employing vehicle-highway cooperation to gain vast improvements in the safety and efficiency of the road-vehicle system has been a part of the ITS program since the beginning. In fact, during the early years of ITS [then called Intelligent Vehicle highway system (IVHS)], the possibilities offered by a cooperative system approach were the central concept that gave momentum to the overall program. In those more visionary days, this cooperation was embodied in the idea of an AHS, whereby roadway elements and communications would interact with automated vehicles to increase road capacity. What is emerging now is a...