Merging Control Research Articles

Specification, Analysis and Validation of Distributed Control System: the ACSY-R Model

We present in this paper an intergrated CASE model for the control part design, the architecture design and the validation of the operational architecture obtained by merging control part and architecture part The control design is based on a set of functional, behavioural and data processing models. The architecture design allows to model the different equipments used. It is based on an object oriented model using the Interpreted Petri nets for the behavioural specification. The validation is supported with a qualitative and quantitative analysis of the operational architecture. A software tool is yet developped and presented at the end of the paper.

FHWA Traffic Research Program

While highways are not always the best means to accomplish all transportation tasks, they must always be made as efficient as possible. Getting the most out of highway plant through electronics can be much more economical than physical highway expansion. Several such developments can help existing highway plant do more, do it more safely, and assist the motorist too. Intersection TV surveillance can lead to reduction of urban intersection accidents. TV surveillance is also applied to certain expressways. Merging control systems can help motorists enter expressway traffic smoothly and safely, and improve expressway efficiency. A large installation is being made in Chicago. Two types of display for merging control are being tested near Boston. Traffic sensing and control in real time by computers can improve urban traffic flow. Such a system, to be tested in downtown Washington with Urban Mass Transportation Administration cooperation, will include bus priority arrangements. Electronic route guidance can help guide drivers to their destinations, redistribute traffic over alternate routes to reduce congestion, and solve other routing problems.

Automatic vehicle guidance and control—A state of the art survey

Highway automation is an attractive possible solution to some of the problems posed by an ever-increasing number of motor vehicles, as it would probably result in substantial increases in traffic-flow rates and a dramatic reduction in the numbers of highway accidents and fatalities. One practical system involves a roadway complex of the future, consisting of both automated and nonautomated roads, which will have evolved in an orderly and progressive manner from the roadway system of today. Only the main highways would be automated, and dual-mode vehicles would be used. The two major related technical areas in this framework are the physical characteristics of the various required subsystems for vehicle guidance and control and the optimum operation of the overall highway system. The elements of the former are divided into eleven categories: automatic longitudinal control, vehicle-spacing detection, communication systems, automatic lateral control, automatic merging control, controlled lane changing, vehicle propulsion, system decision-making capability, compatible manual mode, automatic vehicle checkout, and evolutionary developments. The role and state of the art of each category are discussed in detail, together with the complex interrelationships which exist among categories. Although some research has been accomplished, substantial future research and development progress will be necessary before an automated highway system is a practical reality.

A merging control system for the urban freeway

A computer-directed traffic-control system is described which is being designed under the sponsorship of the Bureau of Public Roads. The system is intended to increase the efficiency and safety of the merging maneuver by detecting and tracking gaps in the merging lane of the freeway and by dynamically controlling ramp vehicles into these gaps. This system is also concerned with optimizing throughput in the freeway corridor by distributing traffic demand between the freeway facility and supporting network of arterial streets. The description of this system is supported by a treatment of the parametric relationships governing traffic control on freeway, and reference to the historical development of merging control systems.

Highway traffic surveillance and control research

The Burean of Public Roads of the U. S. Department of Transportation, through the Traffic Systems Division of its Office of Research and Development, is conducting a research program in the fields of highway traffic surveillance and control. The effort involves in-house, coatract, and cooperative Federal-State research. Being given individual as well as integrated systems consideration are urban highway networks, freeways and rural multilane highways, and two-lane rural highways. Among the many projects trader way or being planned are several major emphasis projects, offering particularly great potential for rapid payoff, together with related theoretical research. These include: 1) an urban traffic control system, utilizing a digital computer, for research into advanced signal control concepts 2) a refined ramp-freeway merging control system 3) advanced freeway flow modelling and surveillance techniques and possible automation of flow 4) a passing aid system for two-lane rural highways, to permit passing on roads with restricted sight distances 5) an electronic route guidance system to supplement signs 6) use of cooperative passing motorists to advise of drivers needing help 7) overall systems analysis of highway communications. Also under way is a broad long-range analysis of the function of transportation.