Piotr Szymak

Decision system for a team of autonomous underwater vehicles-Preliminary report

The paper presents preliminary research whose main goal is to build a ship protection system. One of the elements of the system will be a sub-system responsible for capturing and destroying/neutralizing all dangerous objects occurring inside a guarded area. This task will be performed by a team of autonomous underwater vehicles. To construct a decision system for the vehicles, i.e. the system whose task is to provide high-level decisions regarding direction and velocity of move, many different methods can be applied. Examples are evolutionary neural networks and expert systems with fuzzy decision rules. To test usefulness of the above methods in a role of the decision system, experiments in a predator-prey problem were carried out. In the experiments, the task of vehicles-predators was to capture a vehicle-prey behaving by a simple deterministic strategy. The current paper is a report on all the experiments mentioned.

Analysis of parameters of traveling wave impact on the speed of biomimetic underwater vehicle

The paper is focused on presenting first steps in attempting to build model of the motion of the biomimetic underwater vehicle (BUV) based on experimental studies of traveling wave parameters on the robots speed. In the introduction the mechanical and electronic part of the fifth version of BUV called CyberFish is shortly presented as well as its enhanced motion principle based on traveling wave. The second paragraph covers experiment description and discusses its results.

Selection of Method for Underwater Robot Control

Automatic control of motion of underwater robots, particularly along desired trajectory, requires application of proper controllers taking into account dynamics of the underwater robot and features of the marine environment. In the paper the mathematical model of an underwater vehicle [2] and the architecture of designed control system [4] have been presented. Moreover, selected results of numerical analysis in the form of comparison of different course controllers have been provided.

Course Control of Unmanned Surface Vehicle

The paper considers the problems of controlling a course of an Unmanned Surface Vehicle USV. To select proper course controller, following three methods were tested: PID, slide and fuzzy control. Moreover, to counteract sea current two methods were presented and compared by means of numerical research. In the introduction, the USV called edredon is presented. In the next section, principles of operation of the tested controllers are described. Then, the methods for sea current counteracting are inserted. In the end, the results of numerical research and conclusions from carried out comparisons are presented.

Microprocessor System for Measurement of a Thrust Generated by an Underwater Vehicle

One of the most important elements of a stand for measurement of a thrust generated by an underwater vehicle UV is a microprocessor measurement system. The system is responsible for processing signals from a force sensors and then for delivering processed data to a measurement system. The paper describes the microprocessor system which was built for measurement of a thrust generated by a biomimetic underwater vehicle BUV [4].The paper includes an introduction, technical description of the measurement system and at the end, selected results of its working.

Software architecture of biomimetic underwater vehicle

Autonomous underwater vehicles are vehicles that are entirely or partly independent of human decisions. In order to obtain operational independence, the vehicles have to be equipped with a specialized software. The main task of the software is to move the vehicle along a trajectory with collision avoidance. Moreover, the software has also to manage different devices installed on the vehicle board, e.g. to start and stop cameras, sonars etc. In addition to the software embedded on the vehicle board, the software responsible for managing the vehicle by the operator is also necessary. Its task is to define mission of the vehicle, to start, to stop the mission, to send emergency commands, to monitor vehicle parameters, and to control the vehicle in remotely operated mode. An important objective of the software is also to support development and tests of other software components. To this end, a simulation environment is necessary, i.e. simulation model of the vehicle and all its key devices, the model of the sea environment, and the software to visualize behavior of the vehicle. The paper presents architecture of the software designed for biomimetic autonomous underwater vehicle (BAUV) that is being constructed within the framework of the scientific project financed by Polish National Center of Research and Development.

Research on biomimetic underwater vehicles for underwater ISR

Autonomous Biomimetic Underwater Vehicles BUVs driven by an undulating propulsion are a new branch in an area of an underwater robotics. They imitate both the construction and kinematics of a motion of underwater living organisms, e.g. fishes. Such vehicles have several features crucial from the point of view of military applications, e.g. larger secrecy and potential range of operation. The paper presents results of the research on BUVs carried out within two (Polish and EDA) projects both led by Polish Naval Academy. At the beginning, the initial efforts in building Polish BUV called CyberFish are included. Then, selected results of the tests of subsystems, e.g. navigational and 3D model of BUV built within national project are described. Next, the initial research achieved in the international project are showed. At the end, the schedule of the research planned to carry out within both projects is inserted. The paper is mainly focused on the hardware development of the BUVs.

The hardware implementation of demonstrator Air Independent Electric supply system based on PEM fuel cell

Abstract The paper presents results of the research project whose the main goal was to build a technology demonstrator of an electric supply system based on the PEM fuel cell. The electric supply system is dedicated to operation on a board of a submarine during emergency situations. The underwater conditions influence on a specific architecture of supply subsystems of the PEM fuel cell system. In this case the fuel cell stack is supplied by both clean hydrogen and clean oxygen stored in pressurized tanks. The hydrogen has to be delivered in a closed loop, while the oxygen can be delivered in a closed or an open loop. In the technology demonstrator, the supply of the fuel cell stack by the hydrogen in the closed loop and the oxygen in the open loop with a precise control of its flow were used. In the paper, a hardware and a software structures of the technology demonstrator are presented. Then, selected results of the PEM fuel cell system operation are included. The results of the research show precise control of the oxygen and a response of the system on rapid changes of an electric load responding to the loads working during an emergency situation on a board of a submarine. Mainly, results of the real fuel cell system operation are presented. The results of numerical research can be found in several publications of the authors included in the bibliography of the paper.

Research on Subsystem of Obstacles Detection Based on Physical Model of Biomimetic Underwater Vehicle

One of the most important subsystems of an Autonomous Biomimetic Underwater Vehicle ABUV [3][4] is a navigation subsystem. The subsystem is responsible for safe navigation under and above the surface of water. One of the key function of the subsystem is an obstacles detection. The paper describes the tests of the obstacles detection performed by means of the physical model of the ABUV in a real environment – the marina in Gdynia.

Accuracy of Positioning Autonomous Biomimetic Underwater Vehicle Using Additional Measurement of Distances

Abstract The article describes a study of problem of estimating the position coordinates of Autonomous Biomimetic Underwater Vehicle (ABUV) using two methods: dead reckoning (DR) and extended Kalman filter (EKF). In the first part of the paper, navigation system of ABUV is described and scientific problem with underwater positioning is formulated. The main part describes a way of estimating the position coordinates using DR and EKF and a numerical experiment involving motion of ABUV along the predetermined test distance. The final part of the paper contains a comparative statistical analysis of the results, carried out for assessing the accuracy of estimation of the position coordinates using DR and EKF methods. It presents the generalized conclusions from the research and the problems relating to the proper placement of the components of the system measuring distances.