The concept of the intelligent Vehicle/Highway System (IVHS) is a direct descendent of earlier work on “roadway automation”. Recent advances in a variety of technologies have now made automatic control of the operation of road vehicles a much more realistic proposition than it was even in the recent past. This paper begins by identifying three stages in the likely evolution of these advanced vehicle control systems (AVCS), showing how AVCS is related to the other IVHS functions. The technological elements of AVCS, corresponding to needed research and technology development work, are then described. The current international state of the art in these technologies is reviewed, and the paper concludes with a discussion of an evolutionary progression that could be followed to lead from present-day driving to the long-term concept of an automated freeway network.
