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Abstract

The article presents the analysis of the automatic alternate current motor control system, carried out by the author. The automatic control system has been implemented on the existing laboratory stand, containing: the squirrel-cage asynchronous motor and the frequency inverter. The existing stand imposed one of the available speed control methods for the motor and the necessity of the appropriate elements selection for the automatic control system [1]. The automatic control system has been designed and created as the constant value follow-up digital controller. To designate the parameters of the control object the unit step method of was used. After registering the output changes caused by the unit step, the characteristic curve was received that allowed to determine the alternative transmittance of the control object which, in turn, has made possible to find the appropriate controller settings.

Abstract

The article, on the basis of the underwater vehicle ‘Głuptak’ intended to combat naval mines, outlines the general concept of the microprocessor system of registration of change of electricity stored in batteries for the underwater vehicle at the implementation time of the set task. Registration system the amount of energy allows you to optimize the implementation of the working time of the underwater vehicle drive system in conditions of interference type underwater sea current.

Abstract

The article presents an analysis of performance of an energy storage element used in uninterruptible power supply systems built with the use of supercapacitors. It describes the operation of the voltage balancing system during charging and discharging of the capacitors. Attention has been drawn to the energy conditions of the system's operation and solutions that provide enhanced energy efficiency have been described.

Abstract

This article is one of the series articles relating to the DiveSMART project conducted to improve coordination procedures used in international underwater rescue operations in the Baltic Sea. The project DiveSMART Baltic has received the ‘flagship status’.

The article is the third in the planned cycle of articles relating to efforts made at the Naval Academy within the framework of DiveSMART Baltic project. It includes scenarios of treating decompression sickness acquired by divers during a rescue operation or after completed their decompression. These issues are connected with the work package four ‘Medical treatment’ of the DiveSMART Baltic project: Identifies methods for different medical treatments in operational areas.

Abstract

NATO standardization documents are the basis for action in many areas of NATO military activity and their affiliated organizations. The development of the NATO standardization documentation has been on-going for more than 60 years, and their content provides a reliable basis for joint action in a unified manner, enabling interoperability in many areas of NATO operations. The article is divided into three parts, the first of which deals with the general principles of NATO standardization, the second part describes the standardization documents related to the measurement of the ship’s signatures in aspect of the mine countermeasures and the third describes the participation in research project of NATO — RIMPASSE 2011 Trial. One of the their task was to verify and update NATO standardization documents including AMP-15.

Abstract

This article is a continuation to the theme of the article Operational diagnostics synthesis of the naval gas turbines operated by the Polish Navy published in SJ of PNA No. 1/2017. This article presents examples of results of energy research carried out by the Polish Naval Academy in the years 1985–2016, for the purpose of operational diagnostics of this type of engine, operated by the Polish Navy. The research conducted since 1985 covered four types of naval gas turbines (DE 59, DR 76, DR 77 and LM 2500), with a total of 24 engines. Currently in operation there are four LM 2500 type engines. In the near future, another LM 2500 engine will commence operations, along with a project 661M patrol ship. The energy research covers the engine start-up process, their operation in idle mode and within the whole range of load variations, as well as the process of engine stopping. The article presents examples of characteristics specific to the above processes, determined based on the results of studies of individual types of engines. Currently ongoing studies allow for constructing strategies for naval gas turbines, operated in the Polish Navy, according to technical condition.

Abstract

Due to the growing interest in the problems of cooperation among unmanned vehicles, in the article the proposition of the system for launching a mini unmanned aerial vehicle (mini-UAV) from an unmanned surface vehicle (USV) has been presented. The solution differs from the previously used in this that instead of the commonly used rotorcrafts it concerns the ability to start the mini aircraft with the help of pneumatic or rubber launcher. The results of the computer simulation have con-firmed the possibility of implementation of that kind of system.

Abstract

The paper presents the first part of the final report on all the experiments with biomimetic autono-mous underwater vehicle (BAUV) performed within the confines of the project entitled ‘Autonomous underwater vehicles with silent undulating propulsion for underwater ISR’, financed by Polish National Center of Research and Development. The report includes experiments in the swimming pool as well as in real conditions, that is, both in a lake and in the sea. The tests presented in this part of the final report were focused on low-level control.

Abstract

The article presents the possibility of using unmanned aerial vehicle to perform selected photogrammetric studies. The first part shows the mathematical basis of aerotriangulation based on a series of images. Next, a photogrammetric system consisting of an unmanned aerial vehicle (UAV) equipped with a camera and specialized software for recording and processing images was presented. The main part shows the stages of the photogrammetric processing from the images i.e. mission plan of the incursion, creation of a thick cloud of points and a three-dimensional model. It also shows the analysis of the quality of the developed orthophotomap and a numerical model of the surface area, including photopoints by comparing them to orthographic images that are shared on Google. The final part contains generalized conclusions derived from the conducted research.

Abstract

Due to the safety reason, the ship movement on the littoral area should be monitored, tracked, recorded and stored. Automatic Identification System (AIS) is the perfect tool to ensure this requirement. The limit probability for the AIS dynamic data availability can be limited by the lack of Global Position System (GPS) signal, heading (HDG) and rate of turn (ROT) data in position report. Availability of data link is an additional limitation. For this purpose, it is possible to attach the Discrete Kalman filter (KF) for the position, and course estimation. Coordinate estimation in the absence of a transmission link can improve the quality of AIS service at Vessel Traffic Service (VTS) stations. This article presents Kalman filtering algorithm to improve the possibilities of ship motion tracking and monitoring in the TSS (Traffic Separation Scheme) and fairways area. Only 39 iterations were presented to familiarize how the Kalman filter algorithm works. The archival data from 2006 were used deliberately. During that time, there were problems with the AIS availability service. With the use of measurements series from those years, it is easier to observe the effectiveness of Kalman filter in absence of AIS data.