System Failures on Road Traffic Networks: Can Ergonomics Help?

Abstract

The nature of urbanisation in Western Society requires a certain type of transport system. Conversely, the type of tansport system provided strongly influences our society. When dealing with such complex systems it is unlikely that an investigator will establish fundamental causal relationships. There are many cases of the system being tampered with to achieve one objective, only to find that the secondary results negate any improvements. Thus it is impossible to say exactly why a particular project does not show the expected benefits. Our knowledge and methodologies are just not sufficient. This paper will attempt to show where weaknesses in technique have contributed to the failure (serious non-optimum performance) of some schemes. Emphasis will be placed on illustrating how an ergonomics viewpoint would have alleviated the situation.

Three projects, selected to illustrate the wide spectrum of the problem area, will be simplified and examined. The first is the continuing attempt to provide master control for a network of traffic signals, where the simplistic model of human behaviour used reduces the chances of obtaining good results. The second is concerned with the signposting of motorways and purports to show how ‘ engineering’ solutions to problems and the methodologies adopted ignore fundamental user requirements. The final project is the Bay Area Rapid Transit system. This is used to demonstrate how a simple lack of understanding of human preferences contributed to the poor usage of the system.