Janusz Magaj

Fuzzy logic in the navigational decision support process onboard a sea-going vessel

Ship collisions make up one of the major hazards in marine navigations. The problem of collision prevention in ship encounter situations are characterized. Described with fuzzy logic tools, criteria for the choice of track are discussed. The presented algorithm of ship track optimization in collision situations is based on the method of multi-stage control in fuzzy environment. Finally, the algorithm integrated into the navigational decision support system is presented.

The Problem of Route Determination in Ship Movement in a Restricted Area

Abstract This article focuses on the problem of determining a safe trajectory of a ship proceeding in a restricted area. An algorithm of trajectory choice has been developed, taking into account the parameters of the area, own ship, target ship and other vessels sailing in vicinity. The ship domain has been adopted as a safety criterion. The research results for selected test trials are presented and analyzed. The applicability of the proposed method of trajectory choice in real conditions is considered.

Navigators’ Behavior in Traffic Separation Schemes

One of the areas of decision support in the navigational ship conduct process is a Traffic Separation Scheme. TSSs are established in areas with high traffic density, often near the shore and in port approaches. The main purpose of these schemes is to improve maritime safety by channeling vessel traffic into streams. Traffic regulations as well as ships behavior in real conditions in chosen TSSs have been analyzed in order to develop decision support algorithms.

NAVIGATION DECISION SUPPORTING SYSTEM (NAVDEC) — TESTING ON FULL MISSION SIMULATOR

ABSTRACT The known navigational systems in use and methods of navigational decision support perform information functions and as such are helpful in the process of safe conduct of a vessel. However, none of these known systems provides a navigator with ready solutions of collision situations taking account of all the vessels in the proximity of own ship, where the Collision Regulations apply. Another shortcoming of these systems is that they do not explain the assessment of a navigational situation and proposed manoeuvre parameters. Results of testing in simulation condition of NAVDEC - new Navigational Decision Supporting System developed by research team of prof. Pietrzykowski [Pietrzykowski et al., 2012a], [Pietrzykowski et al., 2012b] - were presented in this paper. STRESZCZENIE Znane, będące obecnie w użyciu systemy nawigacyjne, jak również metody nawigacyjnego wspomagania decyzji pełnią funkcje informacji i jako takie są pomocne w procesie bezpiecznego prowadzenia statku. Żaden z tych znanych systemów nie dostarcza jednak nawigatorowi gotowych rozwiązań sytuacji kolizyjnej z uwzględnieniem wszystkich statków znajdujących się w pobliżu oraz odpowiednich przepisów międzynarodowych. Inna wadą istniejących systemów jest to, że nie podają one oceny sytuacji nawigacyjnej i proponowanych parametrów manewru. W artykule przedstawiono wyniki testowania w warunkach symulowanych systemu NAVDEC - nowego nawigacyjnego systemu wspomagania decyzji tworzonego przez zespół badawczy prof. Pietrzykowskiego.

Safe Ship Trajectory Determination in the ENC Environment

The paper presents the problem of determining a safe ship trajectory in real conditions with the use of information comprised in electronic navigational charts (ENC). Ship trajectory optimisation is one of essential functionalities of decision support systems which are part of intelligent transport systems. An ENC data transformation method herein presented is aimed to reduce the time of creating the numerical terrain model for an optimization problem. Trapezoidal meshes are proposed for this purpose. Water area parameters as well as moving targets are considered. The three dimensional ship domain is used as a safety criterion. The implementation of the presented method is discussed.

Ship Domain as a Safety Criterion in a Precautionary Area of Traffic Separation Scheme

The ship domain is one of the criteria for navigational safety assessment. It is particularly important in restricted areas with high intensity traffic, where the criteria of closest point of approach (CPA) and time to CPA are difficult to apply. This research continues to examine ship domains in Traffic Separation Schemes (TSS). We have analyzed precautionary areas established within TSSs in connection with changed arrangements of vessel traffic. Besides, we have defined ship domains in a precautionary area of a specific TSS, and compared them to domains of vessels proceeding along traffic lanes. http://www.transnav.eu the International Journal on Marine Navigation and Safety of Sea Transportation Volume 11

Ship domains in Traffic Separation Schemes

Ship movement processes in selected Traffic Separations Schemes (TSS) of Southern Baltic Sea were analyzed. Ship domains in the analyzed water areas were calculated from Automatic Identification System (AIS) registered data. The purpose of investigation was identification of ship domain parameters taking into account different domain determination criteria. The results were compared and discussed. The conclusions were drawn.

Automation of Communication and Co-operation Processes in Marine Navigation

The problem of information exchange and communication in marine navigation is presented. The authors propose a sub-ontology for automatic inter- ship communication as a supplement to the ontology of navigational information. The application of the sub-ontology enables the improvement of information ex- change and co-operation between navigators steering the ships. The automation allows to reduce the impact of human errors resulting from the failure to effectively communicate and coordinate actions. The human factor is often to blame for ma- rine accidents. Applications in the ship communication and co-operation system are shown.