COLLISION PREVENTION IN SINGAPORE STRAIT BY USING TIMED PETRI NET

Rino Bošnjak,Pero Vidan,Zvonko Kavran,Danko Kezić

doi:10.3846/transport.2019.11623

Abstract

The problem of maritime traffic in Singapore Strait is traffic density, also the probability of collision, which is increased beside the existing Vessel Traffic System (VTS). The paper discusses the synthesis early warning system, or automatic crossing supervisor for Singapore Strait by using the Timed Petri Nets (TPN). Authors proposes dividing the strait in zones, so called crossings, where routes are crossing and in which the number of ships must be limited. The maximum number of vessels in period of time of the highest traffic density through the crossings are determined. Derived constraints are used for synthesis of crossing supervisor. The authors uses Petri nets to make model Singapore Strait, and use P-invariant method to syntheses crossing supervisor, which limits the number of ships in all critical crossings. Finally, the author verified derived supervisor by using Visual Object Net ++ programme for computer simulation. With the aid of Transas nautical simulator, the traffic in the strait is analysed.

Highlights

The safety of maritime traffic is influenced by a number of factors that may, to a certain extent, affect the safety of vessels, people, property and environment
The presented diagrams indicate the times needed for all vessels to pass through the sectors: S3 = 270 min, S6 = 275 min, S2 = 245 min and S7 = 280 min, naturally, the drawback of the supervisory system is that the traffic flow has to be restricted and, the duration of passage prolonged, in order to increase the safety of navigation
This article suggests an automated supervisory system for early warning, which should be installed to the maritime traffic control centres in order to significantly enhance the safety of navigation

Summary

Introduction

The safety of maritime traffic is influenced by a number of factors that may, to a certain extent, affect the safety of vessels, people, property and environment. Research from the web (MPA Singapore 2019; Singapore DOS 2019) deals with the potential collision risks and possibilities of enhancing the safety of naviga- Approach in this article is collision prevention problem, and it is proposed a new application in VTS centre, so called supervisor. The authors propose a supervisor that monitor traffic in predefined routes in the sectors, and warns a VTS operator in case of TSS violation. In this article research studies is based on enhancing collision prevention in the area of restricted manoeuvring In this area it is not possible to change routes significantly. Authors proposes implementation of early warning computer based supervisor in the VTS centres, which on time alerts VTS operator in case of irregular traffic situations. Verification of proposed supervisor is carried out on computer simulation on example of Singapore Strait

Analysis of marine traffic in Singapore Strait

Methodology for collision supervisor design by using Petri net

Simulation and results

Collision prevention supervisor synthesis and simulation

R3T3 4 R4T3

Conclusions