Discrete Event Simulation-Based Reliability Evaluation of a Traffic Signal Controller

Joong Soon Jang,Sang C Park

doi:10.1155/2018/5986826

Abstract

A mission reliability evaluation methodology for a signal traffic controller is presented in this paper. To develop the new evaluation methodology, this paper combines the Discrete Event System Specification (DEVS) formalism which has been popular in manufacturing area for three reasons: (1) its features compatible with the object-oriented modeling; (2) its rigorous formal definition; and (3) its support for the specifications of discrete event models in a hierarchical and modular manner. By using the DEVS formalism, we construct a simulation model which takes into account not only the characteristics of a traffic signal controller but also the operating environment. Once a model is constructed, it is possible to perform simulation experiments. The proposed methodology computes the mission reliability of a traffic signal controller by using a simulation record, and this information plays a vital role in preparing optimized maintenance policies that maximize availability or minimize life cycle costs.

Highlights

Traffic signals are lights used to control the movement of traffic, and they are electronically operated control devices. e major objective of traffic signals is to control and coordinate to ensure that traffic moves as smoothly and safely as possible [1, 2]
Approach to Simulation Model Construction e strategy of this paper is to evaluate the mission reliability of a traffic signal controller by using simulation technologies
Each simulation experiment generates a simulation log file containing a record of the simulation, which is a sequence of total states, Qi 􏼈(si, ei)|si ∈ S, 0 ≤ ei ≤ ta(si)􏼉, where 1 ≤ i ≤ n

Summary

Introduction

Traffic signals (or traffic lights) are lights used to control the movement of traffic, and they are electronically operated control devices. e major objective of traffic signals is to control and coordinate to ensure that traffic moves as smoothly and safely as possible [1, 2]. A traffic signal controller has four major objectives: (1) maximizing the traffic handling capacity of roads; (2) reducing collisions and waiting time for both vehicles and pedestrians; (3) encouraging travel within the speed limit to meet green lights; and (4) reducing unnecessary stopping and starting of traffic. The definition can be applied to a single component, it is not sufficiently specific to be applied to a traffic signal controller that can be assigned to various missions under various environments. For this reason, we use the concept of a mission reliability to evaluate the reliability of a traffic signal controller. Mission reliability is the probability of nonfailure of the system in the time required to complete a mission profile [6, 7]

Traffic signal controller

SH SL

Discussion and Conclusions