INTELLIGENT TRAFFIC LIGHTS CONTROL BY FUZZY LOGIC

Describes the design and implementation of an intelligent traffic lights controller based on fuzzy logic technology. A software has been developed to simulate the situation of an isolated traffic junction based on this technology. It is highly graphical in nature, uses the Windows system and allows simulation of different traffic conditions at the junction. A comparison can be made between the fuzzy logic controller and a conventional fixed-time controller. Simulation results show that the fuzzy logic controller has better performance and is more cost effective. In the city of Kuala Lumpur, the registration of new vehicles each year increased by about twenty per cent. This increment is rather alarming and even with the development of the LRT and new roads other measures have to be stepped up and introduced as quickly as possible. In Kuala Lumpur the problem of traffic flow during peak hours has somewhat been under control by city traffic policemen. In last February the movement of traffic in the city was chaotic when traffic policemen were taken off their duties of manning the junctions. It was learnt that the Kuala Lumpur City Hall wanted to test their automatic traffic control system that had recently been installed which was still in its initial stage. It is understandabl e that automatic control systems should relieve humans from manual control, however, such automatic system does not work well in many circumstances especially during oversaturated or unusual load conditions which could be due to limitations of the algorithms or sensing devices. In this respect manual control seems to be better due to the intelligence of the traffic policemen in understanding the traffic conditions at the respective junctions. In this paper we discuss the implementation of an intelligent traffic lights control system using fuzzy logic technology which has the capability of mimicking human intelligence for controlling traffic lights. A software based on Visual Basic has been developed to simulate an isolated traffic junction. The control of the traffic lights using both conventional fixed-time and fuzzy logic controllers can be simulated in the software. Analysis on the traffic lights simulation such as waiting time, density, cost, etc. can also be made using the software. The software can also be used as an exercise for undergraduate and graduate students to understand the concept of fuzzy logic and its application to a real environment. The rules and membership functions of the fuzzy logic controller can be selected and changed and their outputs can be compared in terms of several different representations. The software is highly graphical in nature and runs under the Windows environment.