Abstract:Roadway automation is an appealing way to ameliorate increasing traffic congestion. Major programs to examine how to accomplish this are underway in California and elsewhere. Most approaches are emphasizing control of individual cars separated by gaps. In this paper we examine the behavior of mechanically coupled vehicles. We conclude that mechanically coupling vehicles can have significant advantages, especially in the area of system safety in the event of unexpected events such as changes in road conditions or component failure. The core of the paper is a Bond Graph analysis of a platoon of coupled vehicles. This is the first analysis of this type we know of which considers a series of coupled vehicles with the capability of independent control of power and braking to each wheel, and independent steering.

The model is well suited to the study of control algorithms involving all systems parameters. We use the model to demonstrate that modest forces between vehicles can significantly enhance control safety and efficiency. In essence, uncoupled vehicles are limited by the performance of the weakest vehicle, while coupled vehicles can be operated synergistically. To achieve adequate control will require considerable real-time computation. Computer power to meet these requirements is only now becoming acceptably cheap. We conclude with suggestions for future research.