Thoralf Noack

Concept for an integrated PNT-unit for maritime applications

The provision of robust position, navigation and timing (PNT) information is a fundamental element of the e-Navigation initiative proposed by the International Maritime Organization (IMO). In this context the single Electronic Position Fixing System (EPFS), which currently conforms to the minimum carriage requirement, should be replaced by an integrated PNT unit as future onboard integrated system. This unit has the task to collect and integrate data from individual PNT sensors in order to deliver robust PNT information with a specified performance. In this paper the current status of PNT sensors for maritime application is reviewed and first ideas towards an integrity concept for a maritime PNT unit are presented.

ASSESSMENT OF AIS VESSEL POSITION REPORT UNDER THE ASPECT OF DATA RELIABILITY

Abstract Since its introduction the Automatic Identification System (AIS) has played an important part in improving safety at sea, making bridge watchkeeping duties more comfortable and enhancing vessel traffic management ashore. However the analysis of a AIS data set describing the vessel traffic of the Baltic Sea came to conclusion, that specific parameters with relevance to navigation seemed to be defective or implausible. Essentially, it concerned the true heading (THDG) and the rate of turn (ROT) parameters. With the paper we are trying to clarify, which parameters of the AIS position report and to what extent, are affected. The detailed data analysis gives answers on how reliable the AIS data in different traffic areas is.

Initial Realization of a Sensor Fusion Based Onboard Maritime Integrated PNT Unit

This paper introduces the basic concept of the Position Navigation and Timing (PNT) Module as future part of a ship side Integrated Navigation System (INS). Core of the PNT Module is a sensor fusion based processing system (PNT Unit). The paper will focus on important aspects and first results of the initial practical realization of such a PNT Unit, including a realization of a Consistent Common Reference System (CCRS), GNSS/IMU tightly coupled positioning results as well as contingency performance of the inertial sensors.

Deterministic framework for parallel real-time processing in GNSS applications

Starting from the goal developing deterministic realtime applications for high-rate GNSS data this paper shows a number of possible program structures depending on the chosen algorithm complexity using a DLR own software framework. Single-threaded and multi-threaded applications will be compared using a simple example and a real project.

Motion-based consistency audit of onboard Global Navigation Satellite System reference as reported by static Automatic Identification System data

The Automatic Identification System (AIS) is widely used for reporting vessel movements and broadcasting additional information related to the current voyage or constant parameters like the IMO number or the overall dimension of the hull. Since dynamic AIS data is shared mostly without human interaction, and is not flawless, the static AIS content edited manually is vulnerable to human error. This work introduces a simple vessel motion pattern approach that determines the probable foredeck/afterdeck location of the GNSS reference used by the AIS transponder, and compares it to the hull parameters obtained from the static AIS data, to find observable errors in the static AIS configuration of the mount point of the GNSS reference antenna.

Comparison Of AIS-Based Prediction Of The Distance At The CPA With Factual Separation Between Vessels

Abstract Since its deployment in 2004, the Automatic Identification System (AIS) has been considered a significant improvement of watchkeeping duties at sea. According to current regulations, AIS has not been recognised as an approved anticollision instrument yet. However, it would be difficult to rule out a possibility that AIS, being an essential part of the onboard SOLAS — compliant configuration, is unaidedly used for collision avoidance tasks. Recent research activities of DLRs Department of Nautical Systems have shown that AIS transmissions may contain a lot of incomplete data and the system does not have any dependable information on its data integrity. For that reason, the computation of the closest point of approach (CPA) and the time to the CPA (TCPA) are analysed based on AIS data involving multiple vessels, in order to compare the predictions with factual approaches between vessels and to evaluate the usability of AIS data, in its present form, for the appraisal of the traffic situation around each vessel.