Edmonton (Alta.) - 1977 - A transportation management system for the City of Edmonton (1977-01)

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3338 Transportation management Edmonton Transporta

A Transportation Management System for the City of Edmonton

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Contents ii

Foreword 1.0

1

Summary

2.0 Introduction

5

3.0 Transportation Management Goals and Objectives

11

4.0 Transportation Management Characteristics

15

5.0 The Transportation Management Concept as it relates to the City of Edmonton

19

6.0

27

Hardware Concepts

7.0 Recommended System Components and Configuration for the Transportation Management System

31

8.0

Costs and benefits

39

9.0

System staging

43

Appendix 1

Appendix 2

Transportation Management Study Working Papers

47

Bibliography

47

Fo reword In May of 1974 the City of Edmonton, through the Transportation Planning Branch of the Engineering and Transportation Department initiated a major study to analyze existing methods of signalized intersection control and to identify future directions in this field. This study, titled "A Transportation Management System for the City of Edmonton", was completed in December of 1976.

Although outside technical assistance was used for certain specific areas, the study was, for the most part, prepared through city resources. Further assistance, in the form of extensive financial support, was provided by the Province of Alberta, through "Alberta Transportation".

We feel that the study contributes significantly to the solution of Edmonton's transportation problems, not merely in describing methods and tools for effective management of street resources, but also because it enlisted the cooperation of many civic agencies and brought about an increased understanding of mutual and related problems.

Without the cooperative spirit and dedicated effort of many agencies and individuals, this study could not have been successfully completed.

In recognition of their contributions, the following is a list of those agencies: Alberta Transportation Edmonton Fire Department Edmonton City Police Edmonton Power Edmonton Telephones

IBI Group lnographus Ltd. Management Services Tetra Systems Ltd. Traffic Operations

Transit Operations Transportation Planning The University of Alberta

In addition to the above list we would also like to thank the following individuals: D. W. Allan F. Allen K. 0. Anderson G. M. Babey V. Berka L. Casiato R. Charles R. H. David R. Freson R. Friedman

fro.,

D. M. Gafiuk R. Goss N. Irwin G. King 0. Korbutt K. Laubman B. Leng C. J. Lyall D. L. McDonald W. Miller

N. Moroskat M. Palmer R. Rebeiro D. B. Rhyason J. Ruim W. J. Shillabeer L. Turner G. T. Wormsbecker A. J. Van Schaik D. Veljkovic

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S. Teply Special Advisor

J. Schnablegger Project Manager

January 1977, Edmonton, Alberta.

1.0 Summary Introduction The City of Edmonton has experienced significant growth in the past decade. Between 1960 and 1975 the population increased by approximately 68%. Public Services have attempted to keep pace with this growth but shortages of capital and increased costs have made this increasingly difficult. Transportation is no exception to this and all components of the transportation infrastructure must be made to operate at maximum efficiency.

Traffic control is a key variable in optimizing the operations of public and private vehicles operating on the transportation network.

In 1975 the City of Edmonton, through the

Transportation Planning Branch of the Engineering and Transportation Department, initiated a study to examine the alternatives available to Edmonton for improving the transportation control and monitoring element of the transportation network. This study, titled "A Transportation Management System for the City of Edmonton", examined operation of the existing traffic signals and detailed a system which meets the City's existing and future transportation control and monitoring requirements. In order to carry out this task the study examined the operations of North American and European systems.

The study steps are shown schematically in

Figure 1.1 and are described below.

Existing Situation A total of 230 signalized intersections are presently in operation in the City of Edmonton.

Sixty of these signals, located in the downtown area, operate as a linked system which responds in a limited way to traffic fluctuations. The remaining signalized intersections operate in isolation and make minor adjustments in response to fluctuations in traffic.

The equipment outside of the downtown area is of high quality and is in good repair. Portions of the downtown equipment are seventeen years of age and are either malfunctioning or completely inoperative.

An analysis of the existing operation indicated that existing control measures do not have sufficient flexibility to accommodate present demands and will be totally incapable of meeting future demands.

Transportation Management Goals and Objectives The activities of a number of civic departments are directly linked to the operation of the transportation network. The performance criteria for a future system are therefore directly related to the goals of these agencies.

The goals of these various agencies, in relation to the operation of the transportation network, set the parameters for a definition of system requirements. The agency goals are briefly listed below: Traffic Operations maintain level of service in the downtown - maximize the efficiency of vehicular and pedestrian movements increase safety Transit Operations - improve services - improve dissemination of public information improve transit data base

Police - provide the ability to monitor signal performance - improve control during special or emergency events - improve surveillance of specified areas Fire - minimize response time for emergency units Edmonton Power and `edmonton telephones' maintain transportation data base modify system as required Transportation Planning - maintain transportation data base - provide for management of transportation resources

Transportation Management Characteristics The formulation of agency goals provided the basis for the definition of functional characteristics for the system.

This involved specifying the attributes that a system suitable for Edmonton would have to possess. These characteristics are summarized below: Flexibility of Traffic Management and Control - Ability to integrate traffic and transit tactics - Ability to integrate traffic and transit management strategies - Ability to accommodate predictable traffic conditions Ability to accommodate unpredictable traffic occurrences (or incidents) - Ability to provide drivers and passengers with necessary information Ability to monitor and analyze network performance in real time - Ability to maintain a management and planning data base - Ability to communicate with and supervise transit units in service - Rapid provision of information in order to initiate contingency plans

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Ability to provide preference to emergency and police vehicles Reliability of system and system components - Simplicity of maintenance and of failure correction - Capacity for simple human interaction with the system.

Transportation Management System Features The definition of Transportation Management characteristics led to the formulation of specific transportation management measures and strategies. These features were developed through an interactive application of defined system characteristics.

Considerable effort was expended to ensure that the various measures did not thwart the objectives of one agency while satisfying the needs of others.

System features were specified for two levels of operation; the "Basic", which has features that satisfy agency requirements at a minimum level and the "Advanced", which has features that satisfy agency requirements at a reasonably high level.

The "Basic" and "Advanced" systems have the same features but differ in the extent to which various measures are used.

The features are listed below: Data processing and process control.

- A detection and monitoring system - Demand sensitive zonal coordination - Demand sensitive global coordination - Strategic local signal control at selected locations - Integration of light rail transit controls with traffic control - Flexible sign control - Flexible lane control - Manual override of selected local functions - Voice and digital communication with transit units - Interagency communications The degree of complexity of the detection and monitoring subsystem and the application of strategic local signal control are the two prime factors which differentiate the "Basic"

and "Advanced" systems.

Hardware Concepts The means of instituting the identified system measures is a function of the system components and their organization.

The various organizational options are termed hardware concepts.

The approach taken in the study was to initially identify two diametrically opposite concepts that typified the extreme approaches presently feasible. The utility of the two extreme concepts was determined and led to the development of more suitable concepts.

Each new generation of concepts incorporated desirable features of previous concepts while minimizing their disadvantages.

The concept found to be most suitable for Edmonton performs all major functions from a single location, distributes responsibility for various functions hierarchically and provides suitable reliability.

Recommended System Configuration The definition of an optimum hardware concept made it possible to describe in detail the system required for determination of capital and operating costs.

The "Basic" system capable of satisfying the goals and system characteristics as described will utilize micro processors to control input and output activities and two mini-computers; one providing primary control and the other providing background processing capability and system backup for more reliable operation. These two machines will provide the needed control, monitoring and management functions. The "Advanced" system will require additional computing facilities in order to provide more extensive controls. The detection network to be added to the existing system will be based on the use of induction loops. The communication linkages that are expected to connect the intersections to the central control will be provided via a leased 'edmonton telephones' system network.

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Transit, fire, police, and maintenance operations are linked through communication linkages between control centers. In the "Basic" system this would be comprised of normal dedicated telephone lines, while in the "Advanced" system the interagency communication linkages would be supported by automatic channelling of data between control equipment in the various control centers.

The interaction of various components is illustrated in Figure 1.2.

Staging An implementation plan was developed for putting in place the "Basic" system by 1981 and the "Advanced" system by 1986. This would require the inclusion to the new system of approximately 50 intersections per year for 10 years.

The first stage of implementation will replace the existing downtown system and include the Light Rail Transit crossing control system.

Remaining routes will be added from 1981.

Existing controls will also be upgraded from "Basic" to "Advanced" control at this time.

Costs and Benefits Preliminary analysis of the system costs indicated that the "Advanced" level of control is expected to cost 1.66 million (1976) dollars over the next ten years. These estimated expenditures of 1.66 million dollars over the next ten years compares very favourably with the expected system benefits related to improved vehicle operations, reduced accidents and reduced expenditures for control equipment. The expected benefit/cost relationship approaches a 5 to 1 ratio. That is, the benefits to the community will, at a minimum, be five times larger than the estimated costs over the ten year period.

4

2.0 Introduction Edmonton, like other Canadian cities, continues to grow rapidly and its resources strain to keep abreast. Shortage of capital, increased costs, long lead times in the implementation of facilities and social concerns make it increasingly difficult to keep pace with the demand for transportation.

Edmonton, however, has articulated in its Transportation Plan Part I, which was approved

by Council in July, 1974, a philosophy of improving the efficiency of existing network components as an alternative to the exclusive creation of new ones.

Recognition of this philosophy prompted the City of Edmonton to investigate recent technological developments in transportation control and monitoring.

In 1975 the Transportation Planning Branch of the Engineering & Transportation Department was commissioned to define Edmonton's transportation monitoring and control requirements, to develop alternative measures to satisfy these requirements and to outline the benefits to be gained from the application of these measures.

This study was titled "A Transportation Management System for The City of Edmonton".

As the title infers, the study did not limit itself to the operation of traffic signals alone.

The study addressed itself to the operation of the various activities affected by traffic control and developed a system which could improve operation of individual activities through the management capabilities of transportation control. and monitoring.

There are presently 139 North American cities that are operating, developing or planning transportation control and monitoring

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systems. There are an equivalent number of such systems operating in Europe and Asia.

Canada has been a leader in this field with Toronto having one of the first operating systems in the world. Toronto is the only Canadian city with a system in operation, however, Ottawa and Calgary have plans for the implementation of such a system.

Existing Systems Private and public transportation in Edmonton has grown as the City has developed. Figures 2.1 and 2.2 show the historical growth in terms of traffic volumes, transit fleet size, police vehicles, and number of fire vehicles. The present distribution of traffic volumes for 1975 is shown in Figure 2.3 and transit passenger flows for 1975 are illustrated in Figure 2.4.

The existing traffic control system shown in Figure 2.5 consists of 230 signalized intersections, 167 pedestrian signals, 3 roadway links which operate a tidal flow lane control, 35 signals in the downtown which can be preempted for Fire Department priority and 2 intersections which have provisions for transit priority. Of the two hundred and thirty signalized intersections in the City of Edmonton, there are sixty intersections in the downtown area which presently operate as a linked system. This system is referred to as the Programmed Rationing System (PR System).

The PR System was installed in 1958 with the central control equipment located in the Communications Building on 104 Avenue and 100 Street. The system measured traffic volumes on Jasper Avenue and 101 Street and

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these volumes were relayed to the central control equipment which selected the most appropriate of four timing patterns to coordinate the signals under its influence. A major program to determine the reliability, accuracy and performance of the downtown PR System was carried out as part of this study.

In the initial stages of the evaluation, it was found that the traffic surveillance and program selection logic portions of the system were not capable of initiating the control required to cope with existing changes in traffic patterns, because of limitations in hardware.

An analysis of historic traffic volume patterns in Edmonton shows that traffic variations are predictable and stable. This is illustrated in Figures 2.6 and 2.7, where hourly and daily traffic variations are shown. As a result of these findings, the traffic surveillance and logic components were disconnected from the system and replaced by a time switch clock. Selection and initiation of programs was based on traffic counts and historically determined volumes.

Once this change was made, it became possible to evaluate the performance of the timmings with which the system had been programmed. The performance evaluation identified a number of serious problems. Field

Figure 2.4 Transit passenger volumes in 1975

timings at 65% of the intersections differed from the design timing by more than 2 seconds. Field timings at 31% of the intersections differed from design timings by more than 4 seconds. This is at variance with the normally accepted traffic control timing tolerance of plus or minus one second. These deficiencies resulted from three system attributes. One is the complexity of the equipment, which makes it extremely difficult to make exact timing changes. The second is the complexity of the engineering design of the system. The third is the age of the equipment, portions of which have been used for 17 years.

Some components cannot be relied upon to maintain the timings which are set during a programming change.

In order to determine the effectiveness of the existing system timings, (most of which have been in effect since 1969) a computer simulation was performed using the "TRANSYT" signal optimization program. This program was developed approximately 10 years ago in Great Britain and is widely used throughout the world. The simulation indicated that the system was not effectively handling traffic volumes during the critical peak hour conditions. "TRANSYT" was also used to establish new optimized timings. The analysis indicated that major improvements could be

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efficiency, the requirements of the transportation system are increasingly exceeding the abilities of the control system.

achieved with new timing plans. The majority of new timing plans, however, cannot be implemented without major equipment changes, because of limitations of the existing PR System.

All but two of the 170 signalized intersections outside of Edmonton's downtown area feature isolated fully traffic actuated, semi-actuated, or volume-density operations.

This means that each intersection attempts to accommodate flows based on detector information at that intersection alone. It has been shown that in many areas, and under varying traffic conditions, there is a definite requirement for operating these signals in a linked manner rather than in isolation. It has been demonstrated that during saturation flow the isolated traffic actuated operation is a major cause of queue formation and reduced intersection capacity.

Two intersections outside of the downtown system operate under a fixed time mode.

All new acquisitions in signal hardware have been of the solid state variety and therefore incorporate the latest innovations in electronics technology. At present 148 out of the 170 installations are of the solid state type.

Although attempts are presently being made to utilize the existing control and detection components to the limits of their

Implications of Future Growth The inadequacy of the existing control system will become more apparent as demands for transportation services increase. As the City grows peripherally and redevelopment of existing areas occurs, transportation patterns and volumes will change. Figure 2.8 indicates areas of probable expansion. These developments will, of course, cause changes in traffic volumes, transit fleet size, fire fleet size and police fleet size. In response to this growth and to the changes in transportation demand, the requirement for signalized intersections will also increase.

The continued growth of the City of Edmonton will also cause a number of changes in transportation demand. This implies that changes in traffic patterns, mode utilization and volumes can be expected in addition to changes in the network and in policies governing the use of the network.

Many of these changes cannot be determined at this time, therefore a transportation control and monitoring system must have the flexibility to adapt to changing transportation demands.

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3.0 Transportation Management Goals and Objectives The central objective of the agencies that provide transportation for the City of Edmonton can be stated as: "The provision of an efficient transportation system for the City of Edmonton."

The characteristics of a transportation control and monitoring system must complement this central objective by assisting the agencies in attaining their goals. This is illustrated in Figure 3.1. The various agency goals are more fully explained as follows:

Vehicles and pedestrians should be able to use the transportation network with a minimum delay and a minimum number of stops.

Optimally, controls for pedestrian and vehicular movements should be designed to minimize disruption to both.

TRAFFIC OPERATIONS The term "Traffic Operations", as used in this study, covers a number of activities; vehicular movement of all kinds (including transit vehicles), pedestrian movements, traffic management (traffic regulations, one-way streets), traffic signals, reversible lanes and parking management.

TRANSIT OPERATIONS "Transit Operations" involves many activities, some of which relate directly to vehicle operations, and others which relate to other branches of the Edmonton Transit System. Driver allocation, scheduling, vehicle maintenance, passenger information, and the provision of system security are examples of "Transit Operations" activities.

3) Increase safety.

The hazards within the transportation network must at all times be kept to a minimum.

Goals: Goals: 1) Maintain at least Level of Service D in the downtown as utilization of the street network increases.

As volumes of vehicles entering the downtown increase because of peripheral growth and expansion of CBD activity, the level of service on downtown roadways must not be allowed to deteriorate.

1) Improve Services.

The public transportation system must continue to meet the increasing demands for service dictated by growth and changes in mode preference.

2) Improve Fleet Operations.

In meeting the demand for increased service, maximum efficiency of the fleet operation must be maintained in order to provide cost/effective

2) Maximize efficiency of vehicular and pedestrian movements within the network.

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In order that emergency vehicles may respond quickly, special controls are required to limit access to other vehicles and pedestrians.

Similar controls are desirable during special events.

services.

3) Improve Public Information.

The effectiveness of the public transportation system is a direct function of the public's knowledge of the system's operation. It is essential that potential passengers have access to reliable information on operational aspects of the system.

3) Improve Surveillance of Specified Areas.

A number of locations in the city such as bridges, because of their strategic location, require intensive police surveillance. It is important that such locations receive adequate monitoring without depriving the section of manpower which is required for active rather than passive enforcement.

4) Improve Data Base for Transit Planning.

Transit management and planners require continuously updated information regarding performance and operation of the transit system. This information is required in order to make short and long term management and planning decisions.

FIRE This department's main interaction with the transporation system is the use of the street network to respond to emergencies.

POLICE In general the Police Force is given the responsibility for the enforcement of the law. The Traffic Section of the Edmonton City Police Department enforces those regulations and laws that are necessary for the safe and efficient use of the street network. The Police Department also provides manual control of the transportation network when conventional control is incapable of meeting traffic demands. Police point duty is usually required in the event of signal equipment malfunctions, and for controlling traffic during special events or emergencies.

Goals: 1) Minimize the Response Time of Emergency

Goals: 1) Provide the Ability to Monitor Signal Performance.

The performance of traffic control equipment is of vital concern to the Police Department.

If malfunctions occur, or if the signals cannot cope with the traffic demand, police interaction is required to restore normal traffic operation.

It is desirable to minimize the number of personnel required for observation of the signal system and for the performance of point duty.

2) Improve Control During Special or Emergency Situations.

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Goals:

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In order to minimize response time in areas of congestion, enhanced preemption of traffic signals for the movement of emergency vehicles is essential.

1) Maintain Operational Reliability.

The system must operate with a minimum number of disruptions due to electronic component failure. In order to reduce the probability of failure, extensive preventive maintenance procedures are required. If component failures do occur, corrective maintenance measures must be employed promptly.

EDMONTON POWER and 'edmonton telephones' The transportation control and monitoring system consists primarily of sophisticated electronic equipment. The operation of such a system is largely dependent upon the maintenance it receives. Edmonton Power and 'edmonton telephones' provide the required support for major electronic and communication systems in the City of Edmonton.

2) Modify System as Required.

Modifications to the system will be required to accommodate changes in transportation demand and to incorporate new technology.

Modifications should be made at least cost and with minimum disruptions to service.

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TRANSPORTATION PLANNING This Branch is responsible for the development, programming and for the maintenance of a Master Transportation Plan for the City. Systems that affect the operation of various modes, therefore, become major variables in the transportation planning process.

Goals: 1) Maintenance of a Transportation Data Base.

The evaluation of network performance is essential for the planning of short and long term improvements to the transportation system. Such evaluations require extensive transportation data which must be continuously updated. As the size and complexity of the network grows, evaluation techniques must be improved to ensure that the system is efficient and up-to-date.

2) Management of Transportation Resources.

Although the transportation planning process appears to place a heavy emphasis on the expansion of transportation facilities, organizational changes to the existing system are of equal importance. Improved management of the transportation system is essential if maximum utilization of existing resources is to be attained.

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4.0 Transportation Management Characteristics In order to achieve the central objective and to realize the goals of all agencies involved, the system must have certain functional characteristics. These attributes define the basic functional requirements which the system must fulfill. They represent the first general level of system specifications.

All candidate systems must have these features in order to be considered. The degree to which these systems satisfy agency needs is an important measure of their suitability for the City of Edmonton.

Transportation management characteristics are correlated with agency goals in Figure 4.1.

Many of the characteristics listed serve to achieve more than one goal.

The characteristics are discussed in the following section.

shows that these patterns are reasonably stable and predictable. For this reason, they can be effectively dealt with at a macroscopic level.

This level will provide a management framework which will make it easier to implement area wide management strategies tailored to controlling movements on the roads and streets, rather than responding indiscriminantly to demand.

FLEXIBILITY OF TRAFFIC CONTROL will make it possible to adjust to immediate and local demands. Because of the stability of major demand patterns this flexibility will be required only at specific critical locations.

Once again the active role of controls will be emphasized.

RESTRICTIVE CONTROL TACTICS will be implemented on the routes and locations which control the access to the most critical areas of the city — the downtown, and to several areas of special interest such as Rapid Transit at-grade crossings.

FLEXIBILITY OF TRAFFIC MANAGEMENT will make it possible to adjust to major changes in demand. Analysis of transportation demand patterns in Edmonton

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INTEGRATION OF TRAFFIC AND TRANSIT MANAGEMENT STRATEGIES will allow the design of traffic management and control measures with specific regard to transit requirements. Transit management will be able better to cope with the consequences of traffic control measures, limitations of networks, and problems caused by excessive traffic demand.

ACCOMMODATION OF PREDICTABLE AND REPETITIVE EVENTS. Accommodation of special and repetitive events will minimize disruptions to the transportation system caused by both predictable and unpredictable special occurrences such as Clarke Stadium events or fire vehicle responses, respectively.

RESPONSIVENESS TO UNPREDICTABLE EVENTS will allow a reaction to unusual or less repetitive circumstances, such as severe weather conditions, incidents and emergencies.

INFORMATION TO DRIVERS AND PASSENGERS regarding traffic problems will make it possible to redistribute demand by allowing a user of the network a "free choice" in making a diversion to an alternate route or mode.

of the Transportation Management system and for other long term planning purposes.

COMMUNICATION WITH TRANSIT UNITS IN SERVICE will provide a mechanism for taking immediate corrective actions in the event of emergency breakdowns or other disruptive accidents.

SUPERVISION OF TRANSIT UNITS IN SERVICE will have the potential for improved utilization of transit resources, by providing the ability to dynamically allocate and deploy transit resources.

RAPID PROVISION OF INFORMATION IN ORDER TO INITIATE CONTINGENCY PLANS REQUIRING HUMAN INTERVENTION is required in order to maintain a reasonable operational standard for the networks in cases where the automatic portions of the system are not capable of handling emergencies, accidents or breakdowns.

PREFERENCE TO EMERGENCY AND POLICE VEHICLES will ensure that delays to emergency vehicles resulting from traffic congestion can be kept to a minimum.

RELIABILITY OF SYSTEM AND COMPONENTS will ensure that system costs are minimized and that remedial procedures in the event of equipment failure can be effected both speedily and efficiently.

REAL TIME MONITORING AND ANALYSIS OF NETWORK PERFORMANCE is an essential prerequisite for implementation of all the above mentioned characteristics, since up to date knowledge of network status is the basis for meaningful and efficient response.

SIMPLICITY OF MAINTENANCE AND FAILURE CORRECTION will ensure that maintenance can be performed at least cost and with minimum "out of service" time.

MANAGEMENT DATA BASE will provide important data for the implementation of short term plans that could react to such variations in transportation demand as might, for instance, be the result of seasonal changes.

HUMAN INTERFACE (High Level Programming Language) will ensure that the man/machine interface will be effective and easy to use. This is essential for system implementation, operation and modification.

COLLECTION OF PLANNING DATA will provide information for the future development

The characteristics of the system are interrelated with the goals of the agencies. The

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capacity of the system can therefore only be utilized in an optimum manner if all agencies develop systems management strategies and control tactics in cooperation with one another, and then operate the system in such a way that their individual goals will be accomplished in harmony with the common objective. This concept is illustrated in Figure 4.2.

Such a coordinated effort, however, requires an efficient management approach.

Management of the system will depend, to a certain degree, on the organizational structure of the City and the agencies involved.

During the course of this study, management personnel of the agencies under discussion decided that the "City Traffic Engineer" should play a pivotal or coordinating role in the transportation control and monitoring system. All future organizational changes within the agencies and within the City administration in general should attempt to reinforce the links which are required for the integrated operation of the system.

The term "Transportation Management System" was developed to describe the mechanism that provides for the functional integration and management of the City's transportation resources.

17

18

5.0 The Transportation Management Concept as it relates to the City of Edmonton The cataloguing of specific Transportation Management features become possible after the goals of the individual agencies were determined and a definition of system characteristics was developed. The Transportation Management features include specific measures and strategies that could be applied to existing as well as to future transportation systems.

The development of these measures evolved from a multi-jurisdictional analysis of system attributes. This phase of the study was termed "The Interactive Process". During this phase Interactive Process". During this phase representatives of the agencies involved worked together in developing the application of system characteristics. This close cooperation resolved differences in opinion in applying system components and provided each agency with a better understanding of the problems and operations of the other agencies.

System attributes were developed for two qualitatively and quantitatively different levels of operation. These two levels were titled the "Basic" system and the "Advanced" system.

Geographic distribution of features for both the "Basic" and "Advanced" systems are illustrated in Figures 5.1 and 5.2.

It should be noted that although transportation management systems can contribute greatly to the maintenance and improvement of transportation levels of service, they can do this only if they become an integral part of transportation system operations and planning. In order to extract the maximum system potential, the system must be supported by an array of complementary measures such as the development of transit networks, parking policies and road improvement programs.

It is essential that these additional measures be planned and implemented in a coordinated fashion.

In recent years, a great deal of research has gone into the development of systems which would be capable of controlling traffic on an immediate real time response basis.

These systems attempt to adjust controls to varying traffic conditions through the use of flexible dynamic algorithms, without using a predefined control framework. Such systems have been successfully applied in the area of industrial process control. However, the transportation process is so complex that although equipment which is capable of handling such tasks is available, no successfu systems have as yet been developed. Recent research does indicate that some of these dynamic methods may become practical in the future. For this reason, another level of system definition entitled "The Outlook" was kept in mind during the functional design stage. This level of system development would involve direct control of all major local functions from central data processing equipment, based on an extensive surveillance system. These aspects were dealt with only in a very general manner and no detailed geographic specifications were considered.

THE "BASIC" SYSTEM is defined as one which meets goals at a minimum level.

There are no intermediate functional steps in moving from the existing system to a proposed "Basic" system; any intermediate functional step would not represent a significant change over existing operations. This does not mean that geographic stages are not possible in the development of a basic system. The "Basic" system, however, addresses only a limited number of geographic locations and not the entire transportation network.

THE "ADVANCED" SYSTEM is defined as one which meets the goals at a reasonably advanced level. Discrete staging is possible in the evolution of this system from the existing or from a "Basic" system. The "Advanced" system encompasses almost the entire City and addresses the transportation network in total.

The features of both the "Basic" and the "Advanced" systems and their correlation with the system characteristics are listed in Figure 5.3.

The utilization of these features in a "Basic", "Advanced" and "Outlook" system is illustrated in Figure 5.4.

More specific explanations of these features are detailed in the following section.

Both the "Basic" and the "Advanced" systems apply identical or similar measures in providing transportation management, yet the two systems are quite different. The differences in the systems arise from the extent to which system features are utilized and from the difference in the geographic allocation of these attributes between the "Basic" and "Advanced" system.

DATA PROCESSING AND PROCESS CONTROL are essential components in both 19

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21

the "Basic" and "Advanced" systems. Both systems are required in order to process and interpret large amounts of surveillance information, select appropriate control commands and then issue these commands to the control equipment. The system design will be such that repetitive events will be accommodated automatically by preprogramming of the decision making features of the system. Events for which control logic cannot be determined may require human interaction. Nevertheless, people involved in this interaction may use the system for obtaining additional information and may employ the computers for contingency planning.

The "Basic" and "Advanced" systems would use computing facilities of equal complexity.

The differences arise in the amount of computer facility required. The "Advanced" system would require not only more facility but also improved reliability and "interface" facilities for communicating with other computers and as a result of the increased responsibilities.

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THE DETECTION AND MONITORING SUBSYSTEM is that part of the system which identifies the qualified activities in the transportation network. For both proposed systems, there are three levels of data collection.

The first data level is associated with

strategic city-wide control. This is the identification of events at those locations which have an impact on a major portion of the network. Such locations are major routes supplying traffic to the downtown and other major attractors.

The second data level is associated with traffic patterns and events in areas, (of 10- 15 intersections) called zones. Zonal traffic patterns are repetitive. This makes it feasible to predict the direction and volume of prevailing traffic flows and the occurrence of queues.

The third data level is associated with local control. This data level identifies short term traffic variations which can be dealt with locally, but within the confines of more rigid zonal controls. Typical locations for the collection of such data are intersections of major arterial roadways. Such intersections are usually referred to as "critical intersections". One example of such an intersection is 109 Street and Jasper Avenue.

The collected data characterize activity in the transportation system throughout different time periods and can include vehicle and passenger volumes, composition of the traffic flow, speed of the traffic flow, occupancy of lanes, length of queues and the location of specific vehicles in the flow.

The detection devices themselves transmit impulses which the detection and monitoring subsystem, with the use of computing facilities, interprets and transforms into meaningful

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identifiers which can be used in the control process.

The difference, in the detection and monitoring subsystems in the "Basic" and "Advanced" systems, is the amount of first and third level data collection. The differences in the amount of second level data collected between the two systems is minimal.

to the following traffic conditions: Program No. 1 AM Peak Program No. 2 Off-Peak (Daytime) Program No. 3 PM Peak Program No. 4 Light Traffic (Night, Sunday) Special (Special Events, Program No. 5 Adverse Weather, etc.)

The sophistication of zonal controls is similar for both the "Basic" and "Advanced" systems.

DEMAND SENSITIVE ZONAL COORDINATION is a technique which utilizes progressive control of adjacent traffic signals. The existing PR System in the downtown area presently utilizes such control in a limited manner and preliminary analysis has indicated that the technique is applicable in other areas of the city as well. Demand sensitive zonal coordination can result in reduced travel times and delays for all vehicles in the traffic flow. Significant improvements to bus transportation can result if this practice is used in conjunction with other measures such as the relocation of bus stops. These measures have less negative impact upon other modes and are more effective than the signal "preemption" technique.

Both the "Basic" and "Advanced" system utilize demand sensitive zonal coordination techniques.

Zonal coordination measures will be based on the invocation of control programs, which are designed for specific traffic conditions, by the central control equipment. In Edmonton it is possible to design these control programs on the basis of historic conditions, since traffic patterns exhibit pronounced stability. Analysis of historic traffic patterns in Edmonton indicates that as few as five fixed time control programs can deal with all major changes in demand. These programs generally correspond

DEMAND SENSITIVE GLOBAL COORDINATION relates the control measures between zones. This feature is particularly important where it is critical for one zone to accommodate traffic supplied by a previous zone. Demand sensitive global coordination can also be used to control flow in zones which are approaching saturation levels by appropriately restraining the supply of traffic from adjacent zones.

The implementation of global coordination requires an extensive detection and monitoring subsystem and can therefore be utilized more fully in an "Advanced" rather than in a "Basic" system.

STRATEGIC LOCAL SIGNAL CONTROL AT SELECTED LOCATIONS makes it possible to respond immediately to fluctuations in traffic flow, incidents, and demands from transit or emergency vehicles. Flexible local signal control will be used to adjust local controls to traffic demand variations caused by predictable and, in some cases, unpredictable events. Traffic control measures restricting downstream flow can be effected at locations of special importance.

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The control measures used for the integrated operation of the North East LRT Line will be functional components of the entire control system. The proposed implementation of LRT operations necessitated the implementation of these measures before this study could be completed and its conclusions presented. The design of the LRT crossing control is such, however, that it can be incorporated into the overall system at a later date.

In the "Basic" system special control measures such as the LRT crossing system would, to a large extent, operate as separate subsystems. In the "Advanced" system there would be a far more extensive interaction between LRT subsystems and adjacent control areas. The signal control at adjacent intersections would be influenced directly by arrival of LRT trains at various at-grade crossings.

This ability to locally control at strategic locations serves, more than any other single feature, to distinguish the "Basic" from the "Advanced" system. This type of control will be used minimally in a "Basic" system.

However, the "Advanced" system will use this type of control at most intersections of major arterial roadways. The "Outlook System" would go one step further, utilizing this feature at every intersection under the control of the system. It must be emphasized that before a// controlled intersections could operate under these controls, new methods, (as yet unavailable) would have to be developed.

INTEGRATION OF LIGHT RAIL TRANSIT (LRT) AND TRAFFIC CONTROL is a vital feature in sustaining Light Rail Transit and other transportation operations in areas where the Light Rail Transit and other modes cross at-grade. This study addressed itself to the operations of Edmonton's North East Light Rail Transit Line in relation to the operation of the adjacent road network.

The integration of the controls of both modes is accomplished by three major measures: 1. Coordination of the Light Rail Transit schedule and control system with signal controls at adjacent intersections. The objective is the utilization of at-grade crossings

by Light Rail Transit vehicles at times when they are not used by road traffic because that traffic is being held at red signals at adjacent intersections (this feature is similar to but more extensive than the previously described Global Coordination).

2. Demand responsive zonal coordination, in which the control programs for intersections provide an adequate gap which can be used for Light Rail Transit passage in traffic travelling across the crossing.

3. Utilization of special features similar to the flexible local signal control described above.

Such features consist of dissipation of queues on the tracks by preemption of downstream traffic signals, or the introduction of special phase sequences in order to maintain traffic flow despite Light Rail Transit closure.

FLEXIBLE SIGN CONTROL will assist in the implementation of flexible zonal and local coordination, the conveyance of driver warnings and advisories and the implementation of other control measures such as lane controls. The existing message signs on turn bans, for example, are fixed and could not be utilized if responsive control strategies are established. In both the "Basic" and "Advanced" system such signs would be remotely controlled sof as to correspond to the differing control strategies in effect.

Furthermore, messages would be used advising traffic on disruptive incidents and alternate route selection. These signs would assist in identifying queueing in areas where physical limitations in the network cause accidents and follow-up accidents (e.g. Groat Road).

At intersections adjacent to the North East, Light Rail Transit Line such signs will advise drivers of queueing on the tracks and of unusual signal control measures. Speed control measures would utilize remotely controlled driver advisory signs indicating the existence of hazardous conditions on those portions of the network which show a correlation between accidents and speed. An

24

example of such a link is Kingsway Avenue, which, under certain critical combinations of traffic density and speed, experiences extremely hazardous conditions.

The sophistication of sign control is similar for "Basic" and "Advanced" systems. The extent of utilization is dependent on the number of intersections and zones which have flexible control capability. As has been stated previously, this is a function of the monitoring and detection subsystem, and would therefore have limited application in a "Basic" system, but would be utilized extensively in an "Advanced" system.

through manual instruction rather than through system instruction. Override of local function involves the implementation of information and warning signs, and the invocation of restraint strategies in the case of emergencies, maintenance work or equipment failure.

Manual override of system functions is intended primarily for zonal program selection, in response to developments which cannot be detected automatically. Manual override of both local and system functions are not intended as substitutes for automatic control.

However, they do provide important tools for man-machine interaction in the controlling of critical or unusual circumstances.

The level of manual override between "Basic" and "Advanced" systems does not differ greatly. The differences arise in the extent of system override that can be effected.

The "Basic" system, as has been described previously, is severely limited in comparison with the "Advanced" system.

FLEXIBLE LANE CONTROL (Tidal Flow Control) is presently in use on several routes in the City. This control measure is an economical technique for increasing the capacity of a roadway without physically expanding the roadway. It is intended to use this tactic to accommodate changes in transportation and possibly as a tool for upstream control of downstream traffic.

The utilization of lane control is relatively independent of the central control activity in use. The degree to which traffic responsive lane control is used is largely a function of the monitoring and detection subsystems. The "Basic" system would incorporate only a few lane control subsystems. The "Advanced" system, on the other hand, may make more extensive use of lane control measures.

VISUAL MONITORING OF CRITICAL LOCATIONS is a surveillance measure complementary to the automatic detection and monitoring system. Its use is limited to the surveillance of areas of strategic importance which cannot be monitored by more automatic means. Disruptive events, such as parades and accidents, can be controlled in an improved manner if they can be visually observed from a central location. The prevention of crime in transportation facilities (Light Rail Transit Stations) is another important application of visual surveillance. The visual monitoring system would use closed circuit television and remote control television cameras.

The application of visual surveillance is largely independent of the central control facility. Its use is, of course, tied

MANUAL OVERRIDE OF SELECTED LOCAL SYSTEM FUNCTIONS will make it possible for the Traffic Engineer on duty to respond quickly to situations for which control algorithms cannot be developed because of their unpredictable nature. The control features of the system would still be utilized, but

25

necessary to maintain continuous interaction between the agencies involved to ensure that the information flow meets the purposes of the agencies. In addition, a simple system of "Hot Lines" must be established in order to deal with situations requiring human intervention by two or more agencies.

This feature is common to both the "Basic" and "Advanced" system. The "Advanced" system, however, would incorporate more efficient software capabilities for channelling data.

directly to the response that is possible to an identified situation. The "Basic" system would therefore make limited use of visual surveillance. The "Advanced" system can make extensive use of visual surveillance.

VOICE COMMUNICATION WITH TRANSIT VEHICLES would provide radio communication between transit vehicles and a central facility for the identification of incidents (hold-ups, vehicle breakdowns and scheduling problems). The number of vehicles, extent of the bus system, and the manual interaction required limits the application to which this facility can be used and requires the adherence of rigid standards in its use. It is proposed that voice communication would form the transit vehicle communication subsystem of a basic system. It is also possible that, with the use of other measures in an "Advanced" system, voice communications may be adequate.

DIGITAL COMMUNICATION WITH TRANSIT VEHICLES would be the transit communication subsystem in an "Advanced" system. Digital communication would partially alleviate the limitations of a voice system by automatically monitoring the location of vehicles, their adherence to schedules, and in some cases taking corrective action. Other information will be summarized for use only in transit management and planning. Such a system will use specialized radio equipment for the transmission of data and, because of the large volumes of data being transmitted, would require a dedicated computing facility.

INTERAGENCY COMMUNICATION is a major element in integrating the operations of the various subsystems under the control of individual agencies. Selected information collected by one agency will be automatically transmitted to central control and to other agencies requiring the data. It will be

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26

6.0 Hardware Concepts As discussed previously, the definition and application of system measures established parameters which were used to determine the allocation and responsibilities of individual hardware components in the system.

It is possible to assign hardware components in many ways in order to achieve desired system results. The various options of hardware components and their interacting configurations are referred to as hardware concepts.

Even though various concepts can produce the required system features, there are additional factors unique to Edmonton which make some concepts more feasible than others.

These additional factors are briefly discussed below:

presents a considerable investment which has not fully depreciated.

3. EXISTING SIGNAL CABLE A small but fully dedicated cable system forms part of the existing PR system. This system is in good condition and would be available for use in a future system.

4. `edmonton telephones' The City of Edmonton owns and operates the City's telephone system. This means that an extensive communication network is within reach of every intersection in the City.

The hardware concept that is selected for Edmonton must, therefore, provide the required features of the "Basic" and "Advanced" systems and accommodate a number of additional factors unique to Edmonton.

In order to identify such a hardware concept, diametrically opposed extremes in hardware concepts were evaluated and, through an understanding of the advantages and disadvantages of the extremes, an intermediate approach was identified which provided the best overall system utility.

The two hardware philosophies which are representative of the differing extremes are the centralized concept and the hierarchical concept (distributed). All hardware concepts are illustrated in Figure 6.1.

1. GEOGRAPHIC FEATURES OF THE CITY The City of Edmonton is divided into a number of distinct areas because of natural geographic barriers (North Saskatchewan River, ravines) and by a number of man made barriers (railways, roadways). The interaction between these areas, from a transportation perspective, is concentrated on several easily identifiable facilities (bridge, grade separations, railway crossings).

2. EXISTING SIGNAL EQUIPMENT The majority of existing signal equipment is of a reasonable electronic standard and

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Figure 6.1 Hardware concepts 27

The Centralized Concept

intelligence available within the hierarchy.

This severely limits the extent to which the implementation of restrictive control tactics, rapid responses to unpredictable events and the giving of preference to emergency and police vehicles can be provided.

Maintenance of system logic components takes place at several locations, rather than in one location as in the centralized concept.

Since both of the extreme hardware concepts offer distinct advantages, yet have severe disadvantages, two intermediate hybrid concepts were defined in an attempt to exploit the positive features of both the centralized and the decentralized forms. These forms were titled the "cellular" and the "regional" concepts.

This concept is characterized by the concentration of all logical functions in one single location (control center). All information is brought to the control center where it is evaluated and from where all commands are subsequently relayed. Information exchange, comparison and computation are all performed by a large general purpose computer. A typical, but very small, example of such a system is the existing PR System. Larger systems of this type are located in Toronto and New York.

The major advantage of this concept is that all changes and adaptions to the system logic can be performed from a single location. On the other hand, there are several serious disadvantages to this approach. It has only one level of operational hierachy. This means that in the event of computer or communication failure, the system degrades to isolated emergency operation of individual intersections. In addition, the computer is generally grossly under-utilized since it performs primarily simple routine input and output functions and places excessive demands on the communications network.

Finally, programming is complex because three control levels must be accommodated; local, zonal and global. This complexity substantially reduces the ability to adapt the system to changing user demands.

The Cellular Concept This control concept represents a geographically centralized but functionally distributed approach in which the large monolithic computer has been replaced by a number of smaller microprocessors and mini-computers. Within the control infrastructure different tasks are assigned to individual control cells (microprocessor/ minicomputer). Since each individual cell can be designed to overlap a number of functional areas and a number of cells can serve in duplicate back-up capacities, the reliability of the system is greatly increased in the event of failure of any one piece of equipment. This eliminates one of the major disadvantages of the centralized concept. The programming complexity is also considerably less than in the centralized concept, since individual cells are dedicated to specific programming levels.

One major advantage of this concept is the ability to introduce specialized computer technology for specialized requirements. This means that equipment sophistication can vary and therefore be tailored to specific applications. This feature is extremely important for system staging, adaptation, expansion and cost effectiveness. The information and command flows may still be centralized and therefore the demands on the communication network and degradation of system operation in the event of a communication failure are similar to those in a centralized system.

The Hierarchical Concept The Hierarchical concept, also referred to as the distributed concept, allocates logic functions geographically. This system allows local logic to perform local control tasks, zonal logic to control zonal tasks, and central logic to perform global tasks. The geographic distribution of control responsibilityis reflected in the sophistication of equipment required for the various levels. Local and zonal logic is performed by micro-processors of varying capabilities while global control is usually provided by a mini-computer. The major advantage of this approach is the back-up support the varying control levels provide in the event of equipment failure. If, for example, the central computer fails, or if a communication cable is cut, global coordination is lost but zonal coordination can be maintained. If zonal logic equipment fails, local control is introduced only in that zone, while other zones maintain normal operation. Another advantage of the hierarchical concept is the clear definition of programming levels, making logic software far less complex than in the centralized system.

Unfortunately, this concept is incapable of providing flexible local traffic control, since its ability to deal with local intersections is limited by the capability of the lowest level of

The Regional Concept This form is a combination of the centralized and the hierarchical concepts.

Some areas are controlled in a centralized manner, and some zones have decentralized control. A central computer performs all functions for the areas under central control and provides global control of areas under

28

supervision of distributed logic. In addition, central control can override some zonal and local functions in those portions of the system which operate in a hierarchical manner.

The major advantage of this concept is that it can incorporate two control concepts. This provides considerable flexibility in tailoring control to individual areas. The main disadvantage arises from the use of a monolithic computer for more than one level of control, making the software even more complex than for the centralized concept. The reliability of this concept is somewhat better than that of the centralized system, since some zones are assigned control responsibilities.

However, those portions of the system under direct control have no hierarchical support.

The "cellular" and "regional" concepts go much further than the "centralized" and "hierarchical" concept toward satisfying the suitability criteria for the city's system.

Their disadvantages can be substantially reduced by once again merging the best features of each, which has led to the development of the "combination concept".

sub-areas or zones.

This concept extracts the advantages of the centralized and decentralized concepts and minimizes their disadvantages. All major functions are performed from a single location.

There is a reasonable back-up capability and a logical system structure in that local strategy is handled at the local level, zonal logic at the zonal level, and important strategic functions are dealt with at the central level.

Evaluation of Hardware Concepts Each of these concepts is capable of providing the system characteristics that were outlined in Chapter 5.

In order to provide these characteristics, the systems vary considerably in their use of existing facilities, level of hierarchical control, maintenance characteristics and programming complexity. These factors, therefore, determine the differences between the concepts in their degree of utility to the City of Edmonton. The variance of the system utility is illustrated in Figure 6.2 where the factors contributing to a variance are cross tabulated and ranked with various hardware concepts. Concept E is clearly the most suitable.

The Combination Concept This form is a mixture of the regional and cellular concepts. Centralized functions are performed by a cellular grouping of central control equipment. The individual cells are assigned to different functional levels as in the cellular concept, and to geographic

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29

30

7.0 Recommended System Components and Configuration for the Transportation Management System The definition of a recommended hardware concept made it possible to correlate system responsibilities and functions to system components and to define the required interaction between system components. The system equipment falls into five major categories:

CENTRAL CONTROL EQUIPMENT Hardware The grouping of components in the central facility is termed the "system configuration".

The form for the recommended system was predetermined to a large extent by the recommended hardware concept. The intention was that central control functions would be performed primarily by a cellular grouping of central control equipment.

However, a number of options are available for arranging equipment centrally in a cellular manner.

Each processing component located at central control is capable of providing a variety of process control functions.

In order to determine the most suitable configuration alternative, the assignments of the process control elements to processing hardware were analyzed.

CENTRAL CONTROL EQUIPMENT includes all of the central process control logic.

SURVEILLANCE HARDWARE embraces the full range of detection equipment located in the network for purposes of measuring the characteristics of traffic flow.

COMMUNICATIONS EQUIPMENT encompasses the devices and communication lines that transmit information between the various components in the system.

INTERSECTION CONTROL EQUIPMENT consists of all of the hardware that is located on the network (usually at intersections) which provides variable information for the control of transportation.

1. INTERSECTION CONTROLLERS: The actual field control of the intersections from the central computer is performed via the communication processors, intersection communication units and controller interface cards. Successful central control is dependent upon monitoring of intersection equipment and of transportation flow characteristics.

TRANSIT CONTROL SUBSYSTEM describes the area which surveys and supervises transit operations.

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Figure 7.1 Grouping of functions and hardware components 31

2. COMMUNICATIONS: The connection of the local controller to the central computer system is via edmonton telephones' lines.

traffic control plans and the creation of optimized control strategies for the entire network.

8. DATA LOGGING: The recording of all information transfers in the system, in the event that such information may be required for future reference.

3. COMMUNICATIONS INTERFACE: This element is involved in the transmission and recovery of data from the communication lines.

9. ENGINEERING and RESEARCH ACTIVITY: The set of software programs and analytical techniques used by the traffic engineering staff for design of traffic facilities, collection of traffic data, off-line signal timing plan preparation and before and after surveys.

4. WATCHDOG SUPERVISOR: Automatic release of control of the intersection controllers in the event of failure of communications or central control is carried out by this device.

5. INFORMATION PROCESSING: (Data Collection, Selection, Processing) This refers to the processing of input and output data and their routing to the appropriate devices.

10.HUMAN INTERFACE: The human interface for input of control information to the system and display of responses.

It was determined that the optimum configuration is the one which assigns the process control elements into three logically separate modules: - Watchdog Supervisor and communications interface - Data collection and logging - Real time control Figure 7.1 illustrates the grouping that emerges with the assignment described above.

The system schematics for both the "Basic" and "Advanced" Systems are illustrated in Figures 7.2 and 7.3.

6. TACTICAL REAL TIME CONTROL: A central computing device to control actual operation of each local controller in response to the volumes of traffic flow. Tactical control also includes the co-ordination of intersections on major streets or within entire areas in a traffic responsive manner.

7. STRATEGIC DECISION-MAKING: The use of a central computing device to assist in the organization and implementation of area

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32

Figure 7.2 Central control configuration for the "Basic" system

Basic System

provide the linkages between the various process control components.

The input/output typewriter is a two way link between the operator and the computer.

In the "Basic" System, this device provides all printed records of system performance.

The Operator Control console provides for power supply and back-up power switches, alarm identification, real time clocks and manual status device displays. The operator console should be constructed at the outset so as to accommodate future requirements at an advanced control level.

The Cathode Ray Tube (CRT) terminals provide a linkage between operator and computer and traffic signals. This CRT display will be programmed to display signal status, vehicle flow and management records. At the "Basic" level, it is recommended that CRT displays and communication linkages be provided for transit control and `edmonton telephones' maintenance purposes.

The proposed Programmable Data Terminal has been included in both the "Basic" and "Advanced" level systems, in order to facilitate interactive type programming, engineering analyses and some limited data storage.

The three modules illustrated in Figure 7.2 are provided by the communication processor, disk storage and larger mainframe processors (computers).

Communication processors are used as interfaces between the intersections and the main frame processors. They have the ability to format and to concentrate the input data and provide a reserve control in the event of failure in higher level processors or peripheral equipment. These devices are the watchdog supervisor and communication processing module.

Real time control and information processing takes place in mainframe digital computers. In the "Basic" system, several mainframe processors will be used. At the "Basic" level, these processors will be dedicated to specific control tasks such as the LRT crossings system or the CBD system and will have only limited interaction with other mainframe processors.

The data logging module consists of a magnetic disk storage device. The remaining equipment shown in the schematics, such as the input/output typewriters, the cathode ray tube displays and the operators' console Cenh-81 Conl-rol Confiquraiion advanced C.onfrol Le.vel

-

-

CoMMUni cat on

J El

r

vc

Level Computer

1st Level

I-

Corriputer5

@ Input/Output Tainewrita-

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Operator Corio

CRT Nlastar Diaplay

CRT Display

CRT Display

11111_1 -

Transit-

Voice arri Radio System for Transi-1-

Remote Teleprinter

5,

COCCI Figure 7.3 Central control configuration for the "Advanced" system

L

vlimionton l

1,5wer

Remote TelePrinter

Firo

12e.

TeleprinIsr

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Edmonton 1:72war

"Programmable 'Data lgrminal

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33

Advanced System

form of executable processor instructions and is called software.

Control of the proposed transportation management system will be performed by two major software components; the Operating System, and the Application Programs.

The Operating System is the collection of system programs that organizes the central processors and peripheral devices into a working unit for the development and execution of the Application Programs.

The Application Programs perform tasks specific to the control of individual signals, as well as management reporting. Generally, these application programs are any programs written on a program development operating system that is not the Operating System in use.

It is possible for the City of Edmonton to adopt or adapt existing software systems for the needs of the Transportation Management System or, on the other hand, to develop the required software " in house".

Since each computer manufacturer has developed effective and comprehensive Operating Systems programs relevant to his own equipment, it would be redundant and costlrfor the City to redevelop these programs. It is therefore recommended that the computer manufacturer chosen to supply the hardware system should also supply the Operating System. The extent to which the manufacturer will be required to adapt the existing Operating System programs will depend upon the specifications to be developed in the implementation stages of the system.

It is recommended at this stage that the Operating System to be supplied permit concurrent operation of either City or manufacturer supplied real time application programs and application system input/output processing.

In particular the Operating System should include the following functions: - Multiple buffering and queue requests for input/output without delay to the requesting programs.

- Detection, notification and corrective and

Since the "Basic" level of control differs from the "Advanced" level only in terms of degree and complexity of control, the configuration for the "Basic" level need not be significantly different from the configuration of the "Advanced" level in terms of hardware components, except that the "Advanced" system would have more peripheral equipment and more central processors.

The "Advanced" system will have more communication processors since the number of intersections under "Advanced" control is doubled.

At the "Advanced" level, the mainframe processing requires a greatly increased reliability because of the extent of the system.

The mainframe processors would be re-organized in such a way that some processors would be used for process control, while others would be used for strategic decision making and engineering and research activities. The processor not included in process control would continually interrogate the active processors to determine whether they were functioning correctly. In the event that a control processor failed, another one would assume control without impacting the signal system.

The peripheral devices remain much the same as in the "Basic" system. The only changes would be the addition of remote teleprinters as linkages to Police, Fire, Ambulance services and possibly to radio stations in order to provide up-to-date traffic commentaries.

The "Advanced" system will also have a line printer, since the input/output typewriter will not be able to accommodate all printing requirements at this level. The input/output typewriter will be dedicated to logging all keyboard inputs, outputs, status messages and error messages.

Software The actual process, that is the operation of the various components, is brought about by predetermined logic. This logic is in the

34

re-entry action resulting from peripheral equipment failures.

- Servicing of all interrupts and return of network control to the interrupted program upon termination of the interrupt.

As there exist a number of application programs that are either in the public domain, (such as ASCOT and UTCS) or that have been developed by manufacturers, and the requirements of both the "Basic" and "Advanced" systems can be satisfied to a large extent with a number of these existing programs, it is recommended that: The functional specification for the ,application programs to be developed in the implementation stage utilize the more desirable features and algorithms of available programs in conjunction with the unique requirements of the Basic system.

Signal timing base plans required as input to the application programs be defined in the implementation stage of the system.

These timing plans should be developed from the off line signal optimization programs made operational in this study.

The application program to be used should be modular, well documented, fully tested and debugged, proven operational in real environments and written in a higher level language such as FORTRAN, PLI or APL. These recommendations would allow the City to exploit, to a large extent, existirtg programs in order to satisfy the individual short term (2-5 years) demands of the control system. After the five year period, City forces should have developed sufficient expertise to develop their own software for future stages of the system.

expansion may be easily accomplished.

Air conditioning and humidity control: The site environmental control required by the processors and peripheral equipment should include the capacity for cooling, humidification, air reheating and air purification.

Electrical services: The electrical services required on site include lighting, outlets, air conditioning and wiring, under floor power duct systems, emergency power supply and emergency night and exit lighting.

Protection The two classes of protection required relate to fire and personnel. A fire detection and protection system should be given priority. Security control to protect the system from unauthorized personnel is also essential.

SURVEILLANCE HARDWARE Surveillance hardware is required to measure traffic flows and characteristics.

These measurements are derived from sensing devices in the road surface. The majority of sensing devices presently in use in Edmonton are magnetic detectors (200). Most of the existing detectors will not be used in either the "Basic" or "Advanced" system, because of operational deficiencies.

The system will utilize inductive loop detectors because of their relatively low costs and operational advantages.

At present, the cost of installing a complete set of detectors at a typical intersection, with induction loops to detect presence, volume, speed and queue buildups can range from $2,500 to almost $4,000, depending on the location and the extent of use of conduit. In establishing the cost estimates for system detection, it is assumed that the existing detectors in the CBD area, as well as the bulk of the other magnetic detectors, will not be utilized in either "Basic" or "Advanced" level systems, since the placement of these detectors is not required with either the "Basic" or "Advanced" level control systems.

To replace the detectors in the core area with induction loops and to improve a number of key areas, it was estimated that the "Basic" system would require sets of detectors at about 40 locations. This would result in a cost of about $120,000.

In contrast with this, it was estimated that the "Advanced" system would require detector installations at about 130 areas. This would include the previously mentioned 40 locations.

The incremental costs of reaching the "Advanced" system level, in terms of detectors, would be about $270,000.

Space Requirements The central processors and peripheral equipment required in both the "Basic" and "Advanced" systems will require a controlled environment which should be located in an area near the City Hall and Traffic Operations Personnel, yet situated such that communication linkages from the closest 'edmonton telephones' wire centre to Central Control can be minimized. It is recommended that the site requirements, as described below, which are more related to the "Advanced" system, be adopted for both the "Basic" and "Advanced" levels. This will prove more economical since continuing structural and mechanical changes will not be required during system evolution.

Elevated flooring: An elevated floor system is essential to provide space for carrying conditioned air and for easy access to electrical connections and cables. This floor will also provide protection against static electricity build-up and be modular in design so that

35

SYSTEM COMMUNICATION The most reliable method of connecting a local controller to the Central Control processors involves the use of wire pairs. In Edmonton the telephone system is municipally owned, therefore there is already sufficient capacity to meet the needs of the Transportation Management System.

The cost of installing new (dedicated) cable is prohibitive, consequently, it is recommended that 'edmonton telephones' lease the necessary communication linkages to the System.

A prime objective of the communication network is to minimize wire requirements and lease costs while maintaining desired levels of system reliability. Therefore each intersection would be connected to the Central Control via 2 or 4 wire pairs and a limited modulation technique for the transmission of data would be used. This will involve frequency shift keying modulation techniques at a standard 1200 baud data rate. The communication channels will be required to function in a full duplex operating mode with a two to four wire termination at 300 to 600 baud or the standard voice grade type (Class C or type 3002) telephone lines. The communication system would use a polled response technique. Detector data transmission and command and status data transmission would occur on the same communication channel.

It is expected that up to 8 intersections can transmit the detector data on a single channel. The annual lease cost for the provision of communication lines has been estimated, based on the standard 'edmonton telephone' rates. Attempts have been made to have the annual lease cost reflect the increase in communication requirements that would

36

accompany the evolution of the system from the initial control of the Light Rail Transit and Central Business District areas, to the control of the proposed 500 intersections that will require controlling within the planned 10 year design life of the system.

The staging of these costs will parallel, in part, the growth in the number of controlled intersections.

INTERSECTION CONTROL The City of Edmonton presently utilizes vehicle-actuated control equipment. The Transportation Management System would not require such sophisticated local control equipment for intersections under central control.

Intersection controllers would be of the fixed time type. The installation of a fixed time controller as opposed to a vehicle-actuated controller can result in a cost saving of $2,000 to $4,000 per intersection.

The available traffic actuated controllers could be used for expansion of signalized intersections outside of the system.

Some existing controllers, such as those in the existing PR system, will require modification because they cannot be used for isolated control. Such a modification would mainly involve the installation of controller interface and intersection communications equipment.

TRANSIT OPERATIONS

extent, since there is no communication between drivers and control centers.

A number of specific measures in the Transportation Management System are included specifically to improve Transit Operations. The major benefit to Transit Operations will be derived from the co-ordination of signals. Special signal "pre-emption" was also investigated, but was determined to have limited application. In order to provide effective signal priority on a real time basis, it is essential that the system be capable of monitoring individual bus locations and their status. The monitoring of transit vehicles also provides an opportunity for incident reporting, emergency handling and improving schedule adherence. The Transportation Management System design can improve Transit Operations through co-ordination designs, providing pre-emption at required critical locations and by direct communication of the Transit Control Center with the Transportation Management Center.

The extent to which transit measures can be provided is primarily a function of the Transit Monitoring Subsystem and its ability to quickly interpret the data received so that appropriate measures can be taken.

There are a number of hardware approaches which can be used to monitor buses. Discriminatory detectors at intersections can signal the presence or status of a bus to the control center. Signalling devices of the automatic or driver-actuated types can also transmit this data to the control center.

BUS STATUS MONITORING AT SPECIFIC SIGNALIZED INTERSECTIONS In this sub-system, a transit vehicle transmits status information to detectors located at intersection approaches. This data is then transmitted to a control center via land lines. Signal modifications are thus placed on a priority basis and data can be collected for future analysis of bus operations. Limitations on route supervision and emergency handling are similar to those in the system above.

The detection of vehicles and instituting of measures for improving their performance can reach a number of levels of sophistication.

The study examined the full range of existing techniques and their associated costs and benefits.

A brief description of alternative levels of bus monitoring and control techniques is provided below:

DISCREET BUS STATUS MONITORING AT ALL SIGNALIZED INTERSECTIONS This would involve the use of detectors at all signalized intersections plus a transponder on each bus to transmit status information to a control center by digital radio communication.

System-wide impacts could be assessed and signal timing could be modified, at critical signalized intersections. Advisory information such as optimal speeds in order to coincide with green lights could be displayed to drivers.

Status information could also be stored for later off-line analysis in the updating of signal timing plans. The costs to achieve this, however, are three to six times the costs of achieving simpler forms of priority, while the benefits will not likely be in proportion to those of the simpler approaches to signal priority.

This sytem can produce meaningful benefits to traffic and transit operations only if bus monitoring (and not necessarily bus priority) is tied closely to all transit operating functions; that is to the planning of routes and frequencies, to the scheduling and dispatching of vehicles and manpower, to the maintenance of vehicles, to the supervision of bus operations on the street, to the handling of emergencies and relations with the public and to the reporting of system performance to management. This system also has the disadvantage of not having a communication link with the bus driver.

BUS PRESENCE MONITORING AT SPECIFIED SIGNALIZED INTERSECTIONS. This type of monitoring is contrived through the use of discriminatory detectors at approaches to specific intersections. These detectors indicate the presence of a bus to central control. The detection of a transit vehicle is used as the trigger in modifying signal timing to favour transit vehicles.

It is possible to perform route supervision and emergency handling only to a limited

CONTINUOUS BUS STATUS MONITORING In this technique, the presence and status of transit vehicles are monitored not only at intersections, but continuously for traffic and transit control purposes. The transit vehicle location and status is transmitted via radio, rather than through detectors.

This system is based on two-way digital transmission of information between buses and central control. The capacity to communicate with drivers improves the

Techniques for Transit Vehicle Monitoring and Associated Operations Measures

37

associated transit operations strategies.

All of the monitoring and communication requirements should be reviewed upon completion of the various pilot studies and a 10 year development plan should be outlined.

This development plan would then be incorporated in the Transportation Management System.

effectiveness of both normal route supervision and emergency response.

The estimated costs for the systems outlined range from $330,000 to $4,000,000, depending on the degree of automation and extensiveness of the information which will be provided to the bus driver.

Recommended Approach for Transit Monitoring Since any monitoring system can only begin to be efficient if both traffic and transit operations improvements can be effected, and since full scale vehicle monitoring costs are prohibitive, a combination of strategies is recommended.

Communication with drivers is essential for effective emergency handling and route supervision and the Edmonton Transit System should continue its analysis of voice radio requirements. Should this analysis indicate that a voice-only radio system is practical, it is recommended that a pilot test be initiated, involving all vehicles on one major route. This pilot test should be concerned with: - using the voice radio for all classes of emergencies - using the voice radio for a minimum level of route control using voice polling procedures for location loading and other data.

- equipment performance and reliability - transmission characteristics relative to Edmonton.

Should the pilot test indicate that a voice only radio system can be economically justified at the "Basic" level, and can adequately meet Edmonton Transit System requirements, monitoring for signal pre-emption purposes would be via a land line system.

Should the pilot test indicate that voice radio is not adequate and digital capability is required, careful consideration should be given to the type of radio purchased.

Specifications should be such that the radio will be compatible with all future data transmission requirements.

The collection of transit passenger flows is another important monitoring function. The study evaluated a number of passenger counting systems that can be interfaced with the transit monitoring subsystem. Digital radio systems can transmit passenger data in the same manner as vehicle location. If it is determined that digital radio capabilities are required, the transmission of passenger counts should be considered. At present the economic value of continual monitoring of passenger loadings is questionable.

It is recommended that Edmonton Transit System proceed with the development of the portable passenger counter and determine resultant data base requirements and

38

8.0 Costs and Benefits cards. This modification is essential if the computer is to take control of existing controllers and to transmit detector data to central control.

The detailed description of the recommended system makes it possible to outline in sufficient detail the impacts and associated costs of the system. These costs can then be evaluated in the light of expected benefits accruing from such an investment.

-

System Detection: It is estimated that the "Basic" level, when fully installed, will contain 40 fully detector controlled areas, while the "Advanced" system will contain 130 similar areas. Installation costs of $3,000 per intersection were used for the detection system estimates.

-

Software Preparation: The costs indicated for preparing the software include a limited amount of software preparation for management and monitoring reporting and control algorithms. Since the management component of the software system can vary considerably, the costs of creating the system could also vary quite dramatically.

System Costs In order to assess the financial implications of the system and to be able to assess the cost/benefit relationships, system costs were estimated. It is important to note that these costs are indicative of the general magnitude of costs associated with implementation of the "Advanced" system. The cost estimates include the following items: -

-

Master Site Preparations:This includes the preparation of a (preferably) City-owned site of about 900-1,200 square feet. The preparation costs include the installation of air conditioning, humidity control and dust control, in addition to the provision of adequate sub-flooring and wiring, security measures and ensuring of adequate and continuous power supplies.

Technical Implementation Assistance: This component of the project was designed to allow for such activities as the development of functional specifications, tendering, continuing development of signal timing plans, staff training and equipment performance evaluation.

Central Control Displays And Peripheral Devices: This system component includes all computers and peripheral devices required to control the system and to communicate the controlled monitoring and management activities to all divisions, departments and emergency type services. The Basic system configuration is to be implemented in 1978 and 1979 with communication processor costs continuing through. The additional equipment needed to achieve the Advanced system level is to be installed in 1983.

The above system costs, summarized in Table 8.1, do not include the estimates for staffing nor the maintenance associated with the continuing operation and maintenance of the traffic signals outside of the system. In addition, costs for implementing transit monitoring and/or communication/information systems for transit operations have not been included.

In present value terms, the "Advanced" control system would cost about $1,225,000 if implemented over a 10 year period. This translates into an average annual expenditure of $122,000â&#x20AC;&#x201D; $166,000 per annum in 1976 dollars depending upon the method of calculation.

Communication Lease Costs: These costs are associated solely with the lease of dedicated cable from 'edmonton telephones'. The costs shown are based on published tariffs and the use of Bridging techniques to reduce communication lease costs.

System Benefits

Communication Equipment: This component of the system includes the cost for wire terminations and multiplexing equipment.

The major benefit of the proposed Transportation Management System is the ability to manage the City's transportation resources. The ability to control the usage of the system cannot be quantified. However, several specific criteria which are generally used to describe increased transportation performance can be quantified or described in more detail.

Existing Controller Modifications: The cost of modifying some existing controllers involves the installation of controller interface and intersection communications

39

estimates were not utilized in the cost benefit analysis.

The Transportation Management System can be expected to improve: - travel speeds for both auto and transit systems - traffic flow and signal monitoring and management practices - responsiveness to changes in travel demands and planning requirements and to reduce: - travel delays, stops and accidents - local traffic signal controller expenditures and - roadway widening and maintenance costs.

The introduction of a Transportation Management System utilizing a computerized traffic control facility is expected to achieve benefits in each of the above described areas for the City of Edmonton.

SYSTEM STOPS By judicious selection of cycle length, and through the use of fixed and variable progression systems, system stops can be reduced significantly. System stop savings in this sense refer to the vehicle cost savings associated with a reduction in the number of stops. Using average system benefits developed in a number of municipalities that have installed computerized traffic control systems, and by estimating very roughly the number of stops associated with existing levels of congestion, it is estimated that a saving in vehicle costs in the order of 200,000 to 300,000 dollars per annum can be achieved.

These savings arise from reductions in fuel consumption and general vehicle wear and tear (tires, brakes, transmission).

The reduction in number of vehicle stops also reduces vehicle noise and emissions. On truck routes, the co-ordination of signals significantly reduces noise emissions resulting from truck accelerations and decelerations.

REDUCED TRAVEL DELAYS By improving such elements as signal phasing, splits, offsets and cycle lengths, reduction in travel delays in the order of 10% to 40% have been achieved in cities using such systems.

In addition, the introduction of effective progression systems can improve travel speeds by 10% — 15%. An extremely conservative estimate of the reduction in system delays that will occur on a typical peak period work trip is 10 to 30 seconds. Such improved travel speeds could reduce bus and auto peak period work trip times by 1.5 — 3.0 minutes.

Translating the delay improvements into user benefits at an estimated $4 per user hour, annual savings in excess of 1 million dollars per annum may be generated. Since the benefits from reduced stops and accidents are expected to be significant, as noted below, and the use of a monetary value for travel time is at best a debatable procedure, these

ACCIDENTS The introduction of improved signal system controls along major arterial streets tends to minimize the factors which cause certain types of accidents. For example, as the number of stops are reduced, there can be a reduction in the rear-end type of accidents. In addition, improved system operations tend to create more consistent flow patterns, which in turn should lead to reduced lane changing and other risky maneuvering.

The accident related benefits resulting from the system operations are difficult to quantify, but empirical evidence (from such cities as Toronto, New York, and San Jose)

Table 8.1

City of Edmonton Transportation Management Control Study System Cost Estimates (In thousands COMPONENTS 1977 1978 1979 SYSTEM 25 1. Master Site Preparation 75 50 2. Central Control, Displays and Remote Terminals 5 15 3. Communication Lease Costs — 20 10 4. Communication Equipment — — 10 10 5. Existing Controller Modification 40 40 6. System Detection — 25 25 7. Software Preparation (Spec. & Algorithms) 40 60 50 8. Technical Implementation Assistance 85 240 175 TOTALS: 1.0 .935 .873 PRESENT VALUE @ (7%) 85 224 153 PRESENT VALUE:

of 1976 dollars) 1980 1981 1982

1983

1984

1985

1986 Totals 25 10 270

15

15

15

60

15

15

20 30 10

30 40 10

35 40 10

40 50

50 60 —

60 70 —

70 80

325 400 50

40 —

45 —

45 —

45 —

45 —

45 —

45

390 50 150

115 .816 94 40

140 .763 107

145 .713 103

195 .666 130

170 .623 106

190 .582 111

205 .544 112

1660 — 1225

system cannot create it. Through the use of specific strategies, congestion can be spread over a larger area and to alternate routes, thus relieving critical points in the network The application of Transportation Management techinques will have to be closely co-ordinated with the City of Edmonton's operations improvement program, and any savings in expansion construction may be somewhat offset by minor construction, such as bus bay construction and intersection improvements.

If benefits resulting from reductions in vehicle stops, reduction in accidents (with value of personal time omitted ) and lower controller expenditures are compared to system costs, then the sum of these benefits exceeds the system capital costs by a factor of greater than five to one.

Should these quantifiable benefits be ignored, it would still be possible to justify the introduction of the system based solely on the non-quantifiable benefits. These include: - improvements in the ability to respond to changes in travel demands, patterns and management reporting requirements.

- improvements in the ability to monitor system failure, to improve maintenance practices and to provide consistent and accurate traffic data for planning purposes.

Figure 8.1 is an attempt to summarize the system costs and benefits associated with the operation of an "Advanced" control system.

indicates that a reduction in rear-end type accidents by 10% to 20% is not uncommon. If these estimates are applied to the property damage and personal injury type costs associated with rear-end accidents at intersections in Edmonton, savings between .25 and .5 million dollars per annum may be achieved.

LOCAL CONTROLLERS The City of Edmonton presently utilizes vehicle actuated control equipment throughout the City. Introduction of a computerized traffic control system would change this equipment to intersection controllers of the fixed time type. The installation of a fixed time controller, as opposed to a vehicle actuated controller, can result in cost savings of $2,000 to $4,000 per intersection. This suggests that, over the next ten years, the City's plans to add 250 signalized intersections to the system can result in capital savings of .5 to 1 million dollars in expenditures on local controllers.

ROAD WIDENING/CONSTRUCTION By increasing vehicular performance as a result of improved control and monitoring capabilities, it will be possible to defer some construction acitvity by one to five years.

However, it must be pointed out that in areas where capacity does not exist, the signal

'Reductions câ&#x201A;Ź:

Befom

!:::1 a-Rer

Travel Time 15 - zo% Number of 5+ops tz-28%

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Figure 8.1 Expected benefits of the Transportation Management System

Cosf of Local

Controller 50-60%

0%

41

42

9.0 System Staging The successful implementation of the Transportation Management System is greatly dependent on the staging strategy that is undertaken. Although it is technically possible to install the entire system in one stage, it would not be practical. Two major reasons for a staged implementation are discussed below:

STAGE 1 1977-1978 1. Light Rail Transit Crossing control with adjacent intersections. Partial integration of Light Rail Transit and road signal system, demand responsive zonal coordination and flexible local signal control. Detailed specifications have been prepared and the contract will be let in the first quarter of 1977.

a) A detailed traffic engineering analysis and design is required for portions of the network to be placed under system control. The introduction of flexible control strategies will cause significant changes in existing network characteristics. It is impossible to adequately anticipate all of these changes and include them in one design. Through staging, it becomes possible to implement a portion of the system and then include the analysis of its performance in the design of the next stage.

2. Downtown Area Control System. Upgrading and partial substitution of the existing PR System. Demand responsive global and zonal coordination.

b) A staged approach will make it possible to gradually develop the extensive expertise required to design and maintain the "Advanced" system. Such step by step implementation and concomitant analysis will result in increased levels of expertise available for subsequent designs.

The system development should be, therefore, an iterative process that incorporates network priorities and increases the level of expertise of the forces responsible for implementation and maintenance of the system.

These principles led to the definition of three principle stages. These stages are defined below and illustrated in Figures 9.1 and 9.2.

STAGE 1 1977-1978: Inclusion of high (2 years) priority portions of the system, such as the Light Rail Transit Crossings and the Central Business District.

STAGE 2 1978-1981: Gradual development (3 years) of the "Basic" system.

STAGE 3 1981-1986: Gradual development (5 years) of the "Advanced" system.

One of the major benefits of the recommended hardware concept and system configuration is the available staging flexibility. As stages are implemented they do not predetermine the implementation of subsequent stages. This makes it possible to accommodate changing priorities that may result from the development of new areas, changes in the transportation networks, social and political considerations and available finances.

5. 75 Street from Argyll Road to 101 Avenue.

Demand responsive zonal coordination.

3. 87 Avenue from 109 Street to 116 Street.

Demand responsive zonal coordination stragegic local signal control. Designated as testing area.

4. Argyll Road from 75 Street to 111 Street.

Demand responsive zonal coordination.

6. Stony Plain Road from 136 Street to 170 Street. Demand responsive zonal coordination.

STAGE 2 1979-1981 1. 109 Street (88 Avenue - 72 Avenue) Demand responsive zonal coordination.

2. 51 Avenue (111 Street - 75 Street) Demand responsive zonal coordination.

3. 97 Street (144 Avenue - 103A Avenue) Demand responsive zonal coordination.

4. 82 Street (137 Avenue-Jasper Avenue & 95 Street) Demand responsive zonal coordination.

5. 66 Street (137 Avenue - Fort Road) Demand responsive zonal coordination.

6. 127 Street (137 Avenue -118 Avenue) Demand responsive zonal coordination 7. 118 Avenue (127 Street - 124 Street) Demand responsive zonal coordination.

8. 109 Street (103 Avenue - Kingsway) Demand responsive zonal coordination.

43

1977-1978 Stage 1.

Legend Demand 5ensi4ive Zonal Coorclina+ion 5-h-a-kgic Local

â&#x20AC;&#x201D;6â&#x20AC;&#x201D; Signal Control

area of I rai-ecl Vapid Tr&isft and Traffic Control

Figure 9.1 Transportation Management System, Stage 1

44

1979-1981 5-fage

pâ&#x20AC;˘Mr

LEAgend Demand Sensi-l-ive Zona I Coord flexible 5pcecl Con-frol

Figure 9.2 Transportation Management System, Stage 2

45

Therefore, rather than attempt to provide a description of the staff requirements of the Traffic Management System, an attempt was made to describe a conceptual framework for the activities of the Traffic Management group, and a definition of the activities and the number of staff required to implement, over the next years, the Traffic Management System.

Figure 9.3 illustrates the conceptual framework for the traffic control process. The objective of the diagram is to illustrate the level at which Traffic Management staff involvement is required for operating the system.

The activities, as described, will require the full time services of two to three professionals. That is, one to two intermediate engineers and one specialist or junior engineer under the supervision of a senior engineer. The specialist would be responsible for the hardware/software activities. Whether two or three professionals are used depends upon the training and experience of the individuals, as well as the ability of the City to provide nominal support services in terms of technicians.

The question of whether or not this staff requirement can be accommodated within the present structure and priorities of the existing Traffic Engineering Department can only be answered through an assessment of the existing staff loadings, an analysis of the extent to which priorities and existing staff can be re-assigned, and through the use of external resources such as Management Services personnel, Edmonton Power, 'edmonton telephones' or external consultants.

9. 111 Avenue (95 Street - 124 Street) Demand responsive zonal coordination.

10. 124 Street (118 Avenue - Jasper Avenue & 116 Street) Demand responsive zonal coordination.

11. 107 Avenue ( 95 Street - Mayfield Road) Demand responsive zonal coordination.

12. 111 Avenue (124 Street - Mayfield Road & 107 Avenue) Demand responsive zonal coordination.

13. 137 Avenue (Fort Road - 137 Street) Demand responsive zonal coordination.

Staffing The implementation and operation of a Traffic Management System for the City of Edmonton will require changes or increases in City Traffic Engineering staff.

Although guidelines are available for determining the number and class of staff required to administer and maintain the traffic engineering function of the City of Edmonton, these guidelines should be used only in conjunction with a thorough assessment of the existing goals and activities of the Traffic Engineering group and an assessment of the experience and level of training of the individuals that comprise this group.

"Personnel adrivity LevEl

ManElgerriertf Proccss ivlailum and Long Term "Plennall

5fratelic.

TIc+ics1

Operafonal

Figure 9.3 Personnel Management Process 46

Appendix 1

Appendix 2

Transportation Management System Study Working Papers

Bibliography

WP

#1

1. Alberta Department of Transportation, Vehicle Detection Methods, 1975, Upublished.

Agency Goals and Objectives

#2 Existing Traffic Signal System (excluding the downtown 'PR' System) #3 The Existing Traffic Signal System (The Downtown 'PR' System) #4

Management Aspects of Transportation Control and Monitoring

5. Bakker, J.J. & Palmer, F.M., Operating Strategies for Bus Transit in Edmonton Annual Conference Proceedings, RTAC, Calgary, Sept., 1975.

Light Rail Transit At-Grade Crossing Designs

6. Barney, A.F., Communication System Technology and Its Use in Traffic Control Systems Traffic Eng., August, 1971.

#7 Data Collection #8 The Data Interpretation System

7. Bisell, H.H. & Kay, J.L., Evaluation of First Generation Computer Traffic Signal Control Strategies, ITE 45th Annual Meeting, 1975.

#9 Definition of Data Flow #10 IBI Interim Report Hardware Concepts Alternative Configuration Costs Staging Benefits #11

8. Brand, D., Urban Traffic Control: How Far Can We Take It?, Traffic Eng., August, 1972.

9. Bulman, D.H., Cost Utility Experience in the New York State Topics Program, ITE Annual Meeting, 1974.

LRT Crossing Control Tender Documents

10. Casper, G.W., Mancini, R.A., Sultan, G., The Development of Boston's Computerized Traffic Control System, Traffic Eng., April, 1975.

#12 Loop Detector Evaluation and Installation Analysis #13

PR System Conversion to Time Clock Operation

11. Chapman, H.R. & Raynor, I-1.M., Measures of Effectiveness of a Centralized Traffic Control System, Traffic Eng. March, 1972.

#14 PR System Data Collection Program

12. Chapman, M.R. & Clark, J.E., Application of RUNCOST for Evaluation of a Hybrid Traffic Control System, Traffic Eng., April, 1975.

#15 Evaluation of PR Timmings #16

3. B.C. Hydro Publication, A Proto-type Transit Vehicle Monitoring System, March, 1975.

4. B.C. Hydro Publication, Vehicle Location System, Pilot Project, Report on Computer Facility, February, 1975.

#5 Light Rapid Transit Crossings and Intersection Control #6

2. Asim, J. Al-Khalili, Criteria for Defining Sub-Areas for Use in Computer-Controlled Area Traffic Networks, Traffic Engineering & Control, June, 1975, pp. 280-281.

Computer System for Signal Design

13. Civil Engineering, Los Angeles Tackles Freeway Congestion, Editorial, September, 1975.

47

14. Federal Highway Administration, Dallas Freeway Corridor, Research and Development Program Fiscal 1974, (FHA).

29. Klatt, R.T. & Wilshire, R.L., Buying a Signal System: A Two Step Procedure, Traffic Eng., April, 1975.

15. Federal Highway Administration (FHWA), Manuals of Project 2B, Development and Testing of Advanced Control Strategies in the Urban Traffic Control System (UTCS).

30. Kligman, E.J., Automated Traffic Control Software - How Much Does It Cost?

Traffic Eng., October, 1973.

16. Foss, W.B., A Buyer's Guide to Computers, Financial Post, November 15, 1975.

17. Gillam, W.J., Leicester Signals the Way Ahead, Traffic Engineering & Control, November, 1974.

18. Godfrey, K.A., Computerized Traffic Signals: Good For My City?, ASCE Civil Eng., Vol. 45, No. 11, November, 1975, pp. 76-81.

31. Kreek, J.B., A Cornparision of Predictor Algorithms for Computerized Traffic Control Systems, Traffic Eng., April, 1975.

32. Long, H.H. Jr., Arvada's Signal Control System, Traffic Eng., May, 1972.

33. MacGowan, C.J. & Lum, H.S., SIGOP or TRANSYT?, Traffic Eng., April, 1975.

34. MacGowan, C.J., Bus Priority and Bus Preparation in the Urban Traffic Control System, ITE 45th Annual Meeting, 1975.

19. Hall, P.W., Auckland Central Area Traffic Signal Control System, Traffic Engineering & Control, January, 1975.

35. Mierzejewski, E.A., The Economics of Transportation Control Strategies For Reducing Air Pollution, Traffic Eng., October, 1973.

20. Hemhill, J. & Surti, V.H., A Feasibility Study of a Reversible-Lane Facility for a Denver Street Corridor, TRR No., 514/1974.

36. Muzyka, A., Fantasia, J.F. & Goodman, J.M., Bus Operation and Energy Conservation, Traffic Eng., November, 1975.

21. Heymann, G., Verkehrstechnische Systeme und Wirksamkeit Rechnergesteuerte Lichtsignalanlagen in Staedtischen Strassennetzen, Strassenverkehrstechnik, Heft 2 & 3,,1970.

37. NCHRP, Guidelines for Design and Operation of Ramp Control Systems, Research Result Digest #86, March, 1976.

38. Nenzi, R. & Anglisani, G., Real Time Computer System Controls The Naples To//way, Traffic Engineering & Control, February/March, 1974.

22. Hindiyeh, 0. & Muchowski, S.J., User Selected Information Retrieval System, Traffic Eng., August, 1971.

23. Holroyd, J. & Hillier, J.A., Area Traffic Control in Glasgow, Traffic Engineering & Control, 11(5), September, 1969.

39. Peat Marwick Livingston & Co., Traffic Signal System Study, Summary Report Dept. of Transit and Traffic, City of Baltimore, Maryland, February, 1969.

24. Hoppe, K. & Vincent, R.A., Public Transport Priority in Signal Controlled Networks, UIPT Revue 4/1972.

40. Pinell, C., DeShazo, J.J. & Wilshire, R.L., Area Wide Traffic Control Systems, Traffic Eng., April, 1975.

25. I.T.E., Traffic Signal Timing Optimization Techniques for Area Networks, Newsletter, Can. District, Vol. 2, No. 2, July, 1974.

41. Pinell, C., Rosen D., Wilshire, R.L., Development of a Traffic Control Systems Handbook, Public Roads, Vol. 38, No. 2, September, 1974.

26. Kaplan, J.A. & Powers, L.D., Results of SIGOP-TRANSYT Comparison Studies, Traffic Eng., September, 1973.

42. Rach., L., et.al., Improved Operation of Urban Transportation Systems, Traffic Signal Control Strategies, MOT Canada, MOT Ontario, Metropolitan Toronto, March, 1974.

27. Kay, J.L., Signal Systems Studies: A New Approach, Traffic Eng., January, 1970.

43. Rach. L., Lam J.K., Kaufman, D.C. & Richardson, D.B., Evaluation of Off-Line Traffic Signal Optimization Techniques, TRR #538/1975.

28. Kay, J.L., Cost Utility Analysis Procedure for Evaluating Alternative Systems.

ITC - Annual Meeting 1974.

48

44. Rebeiro, R.B., The Birth and Future of the Traffic Management Centre, Annual Conference Proceedings RTAC, Calgary, Sept., 1975.

51. Sperry Systems Management, Traffic & Bus Transit Study City of Los Angles.

52. Stadtplanung Bern, Area Traffic Control in Bern, Bern, 1974- Visitor Kit.

45. Raus, J., Urban Traffic Control/Bus Priority System (UTCS/BPS), A Status Report, Public Roads, Vol. 38, No. 4.

53. Steierwald, G., Bewertung verschiedene Konzeptionen zur verkehrabhaengigen Signalsteuerung, Strasse, Bruecke,

46. Robertson, Dl., Program to Keep Traffic Flowing, Plessey Electronics, Publication No. 6618.

Tunnel 8/1971.

54. Stockfish, C.R., Guidelines for Computer Signal System Selection in Urban Areas,

47. Robertson, Dl., TRANSYT, R.R.L. Report LR 253, 1969.

Traffic Eng., December, 1972.

55. Stout, T.L., Summary of Project 3 - 18 (3)

48. Robertson, D.I., The Use of the TRRL TRANSYT Method, Traffic Engineering & Control, December, 1975.

"Traffic Signal System Surveys",

National Cooperative Highway Research Program, Research Results Digest No. 88/March 1976.

49. Robertson, D.I. & Vincent R.A., Bus 56. Tarnoff, P.J., The Results of FHWA Urban

Priority in a Network of Fixed-Time Signals, R.R.L. Digest, LR 666.

Traffic Control Research: An Interim Report, Traffic Engineering, April, 1975.

41. Rosdolsky, H.G., A Method For Adaptive Traffic Control, Transportation Research, Vol. 7, 1973.

57. Teply, S., Koordinierte, verkehrsabhaenige Signalsteuerung.

Strassenverkehrstechnik, 3, 1971.

42. Rudland, P., Cableless Linking of Traffic Signals (Plessey Traffic & Instrumentation), Traffic Engineering & Control, May, 1973.

58. Teply, S., Integrated System of Area Traffic Control in Towns, 10th International Study Week in Traffic and Safety Engineering, Rotterdam, September, 1970.

43. Ruhnke, D., Collection and Evaluation of Traffic Volume Data for Traffic Dependent Selection of Signal Plans in Hamburg,

59. Teply, S. & Bell, W.P., Are We Demanding

Siemens Review, January, 1969.

Enough From Our Computers?

Compendium of Technical Papers, ITE 45th Annual Meeting 1975.

44. Sacuto, E., A Methodology to Improve Traffic Regulations on an Urban Signalized Network, (Unpublished M.Sc.

60. Traffic Engineering, Computerized Traffic Control Systems, Editorial, April, 1975.

Thesis) Department of Civil Engineering, University of Alberta, 1974.

45. Schlaefli, J.L., Computerized Traffic Control Systems: A Future, Traffic Engineering, June, 1972.

61. Traffic Engineering, Chicago Project

46. Siemens Publication, Parkplatz Information System, 1974.

62. Vincent, R.A., Area Traffic Control in Bern, Traffic Engineering & Control, February, 1972.

Named Outstanding by NSPE,

Editorial, May, 1972.

47. Siemens Publication, Traffic Dependent 63. Vincent, R.A., Traffic Survey Equipment

Signal Control by Means of Traffic Control Computers VSR, 1969.

for Measuring Journey Time and Stopped Time, RRL Report LR 65/1967.

48. Siemens Publication, Siemens Traffic Control Computer System 16000, 1973.

64. Vincent, R.A. & Hoppe, K., Public Transport Priority at a Signal Controlled Junction: An Experiment in Bern, Switzerland, Traffic Engineering &

49. Signalbau Huber Munich, Park Guiding Systems - PLS.

Control, December, 1970.

50. Signalbau Huber, Verkehrsautomation, Munich, 1967.

65. Weinber, Ml., etal., Digital- ComputerControlled Traffic Signal System for a Small City, HRB Program Report 29/1966.

49

66. Whitehead, D. & Beere, D.M., Bus Priority at Traffic Signals, Annual Conference Proceedings RTAC, Calgary, September, 1975.

67. Wilshire, R.L., The Benefits of Computer Traffic Control, Traffic Engineering, April, 1969.

68. Wohrabe, W., Verkehrsabhaen gig gesteuerte Strassenverkehrssignalanlagen, Der Verkehrsingenieur, October, 1969 (21.JGNG).

69. Woods, D.L, Fundamentals of the Induction Loop Detector, ITE Technical Notes, Vol. 1, #4, July, 1976.

70. Wright, C.C., Speeds, Flows, and Journey Times on Road Links in West Central London, Traffic Engineering & Control, January, 1975.

71. Yagoda, H.M., Principe, E.H., Vick, C.E. & Leonard, B., Subdivision of Signal Systems into Control Areas, Traffic Engineering, September, 1973.

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