Introduction In this unit we will investigate the basic principles of traffic signal design. We will consider only the case of an isolated intersection with no conflicting traffic movements. In this sense the notes lay the foundations to signalised intersection analysis.
Objectives: After completing this topic, students should: ÷ Understand the reasons for signalising an intersection ÷ Be able to define the main parameters of traffic signal operation ÷ Understand the saturation flow model for a signalised intersection ÷ Be able to analyse simple intersections ÷ Understand the basic elements of signal hardware ÷ Be aware of broader issues in signalised intersection operation.
Resources The major references for current Australian traffic signal practice are: Akçelik, R. (1981) Traffic Signals: Capacity and Timing Analysis, ARRB, Melbourne.
AUSTROADS (1993) Guide to Traffic Engineering Practice Part 7: Traffic Signals, AUSTROADS, Sydney.
A useful introduction to the general principles of intersection design, including isolated and networked traffic signals, can be found in Chapter 5 of: Ogden, K.W.
Typical light mounting in Calgary, Alberta, Canada...
Marshalite traffic signal. Formerly fitted in vari...
English: Installation of a traffic signal in San D...and Taylor, S.Y. (1996) eds. Traffic Engineering and Management, Monash, Clayton.
The above resources are all Australian based. A good start for an understanding of practice elsewhere in the world is Chapter 9 of: Pine, J.L. (1992) ed. Traffic Engineering Handbook, 4th Edition, Prentice Hall, Englewood Cliffs, N.J.
A very full account of intersection control is found in: Jourdain, S. (1992) Urban Intersection Control, The Book Guild, Lewes, Sussex.
Chapter 6 of this book presents a European perspective of the issues covered in this unit.
Traffic Signal History What are Traffic Signals? Modern traffic signals are generally banks of lights used to control traffic. By a universally agreed convention an illuminated green light means "go", a red one means "stop" while an amber light means something in between. In Australia an...