Solid State Phenomena Vol. 196

Abstract: Main problem in operation of diagnostic systems of power transmission systems is analysis of the energy of these harmonic components of the signal, which could be considered as diagnostic symptoms. Measured values can be affected i.a. by energy of random effects or other, less important components of the signal. Coherence and correlation functions are ones of classical methods of signal analysis being applied to analyze deterministic signals affected by random noise. In time domain autocorrelation function allows to determine time cohesion between adjacent fragments of analyzed process, shifted by different time values. In the paper author describes the method of minimization the impact of disturbances on signals being analyzed using basic properties of autocorrelation function. For the analysis of deterministic phenomena (including nonlinear) ordinary coherence function was applied. Showed examples were implemented and solved in MATLAB environment. The method was verified by analysis of model signals and signals (vibration accelerations) recorded on real object.

Abstract: The process of identification of the parameters of a mathematical model of any dynamic real object necessitates performing the relevant number of measurements with the accurate precision of the quantities that characterize the current temporal state of this object (i.e. object’s vector of state). The accurate identification of the parameters of such a model is achievable only with the help of an especially designed system of acquisition and measurement. This article describes the mathematical model of ship’s synchronous generator with the presupposed simplifications, the parameters of this model and the methods of its determining. There is also presented the conception of the system of acquisition and measurement (based on CompactDAQ platform produced by National Instruments), which is indispensable for identifying the parameters of this model.

Abstract: Applying diagnostics consisting in evaluation of deformation based on corrosion potential measurements it is possible to extend lifetime of technical structures and make them safe for people and environment. Development of anticorrosion techniques and staff training is a fundamental requirement for safe exploitation of technical structures made of 7xxx aluminum alloys. Corrosive marine environment enforces engineers and technicians to implement advanced anticorrosion methods to make life on ship much safer. The paper presents selected problems connected with safety of exploitation of welded constructions made from 7020 and 7020M alloys in marine environment and a new method of corrosion diagnostics. Mechanical properties of the welded joints made from different kinds of binder have been determined. Corrosion resistance of these joints without anticorrosion protection has been investigated in seawater environment.

Abstract: The paper presents a physical and mathematical model of a short range missile launcher based onboard a warship. The conducted numerical simulation allowed for developing an analysis of the anti-aircraft assembly dynamics. The selected responses of the system are demonstrated in the form of physical values characterizing the launcher motion.

Abstract: This paper contains hyperbaric test facility equipped with swimming simulator description dedicated to diving apparatuses decompression research. This stand has been constructed within two scientific projects financed from research funds from the Polish Ministry of Sciences and Higher Education in 2009-2012 and it was realised in the Naval Academy of Gdynia.

Abstract: Ship shock tests have been conducted for shock qualification of hull integrity and proper operation systems and subsystems. The ship shock trial identifies design and construction and it also validates shock hardening criteria. The main problem is that ship shock trials are costly. Numerical modeling and simulation, using FEM, may provide information to look into the details of fluid model, dynamic characteristics of ship hull and its internal component. The ship shock modeling and simulation has been performed and the predicted results were compared with ship shock test data made into sea trials. The preliminary studies of shock analysis approach are presented and the important parameters are discussed

Abstract: In the paper an application of vision methods and algorithms in various domains that contribute to mechatronics is presented. Regarding mechatronics devices and machines as robots, a vision system employed for a testing station simulating an industrial assembly line is discussed. Some numerical aspects concerning image pre-processing, analysis and geometrical transformations commonly used in robotics were introduced. To accomplish an effective investigation, the developed methodology and algorithms were implemented and verified on an experimental setup composed of two industrial robots and automation devices cooperating with two various vision systems. In the case of underwater robots for tank inspection, image pre-processing and analysis algorithms for the robot's position estimation, an image scale calculation and wall crack detection were investigated. An active vibration control system is treated as a mechatronic device which contains mechanical parts, electronics and software. In this example, a visual servoing architecture based on image features for controlling an active vibration control system was examined. For an effective investigation and synthesis of visual servoing algorithms, a MATLAB/Simulink/dSPACE hardware–software environment was employed. A vision system was used to analyze vibration amplitude of the vibro-isolation mass of the active suspension system and to provide a feedback control signal. The connection of 3D vision techniques with modal analysis was shown. Within the confines of the project a methodology for amplitude of vibration measurement and a software tool for modal analysis realization based on visual data were developed. The 3D measurements and structure of the construction were obtained by application and development of passive 3-D vision techniques. From this area, ‘structure from motion’ techniques were developed. In the experimental research, a mechatronic test stand was designed and manufactured enabling automatic two-axis control of a camera. A frame structure was built, in which a guiding-rail system was mounted enabling straight-line motion of a camera. Additionally, a system realizing rotational motion of a camera was built in. To control the experiment stand, software was created enabling the combination of the hardware-software part of the stand with the software part of a vision system. A tool was developed for the purpose of modal analysis and estimation of the quantities characterizing dynamic properties of the structure based on vision signals. As a conclusion, the presented, implemented and tested vision methods in various hardware-software programming platforms are discussed

Abstract: Contemporary empirical researches on the object, which is combustion engine, are processed basing on the theory of experiment. Available software applications to analyze the experimental data commonly use the multiple regression models, which enables studying effects and interactions between input values of the model and single output variable. Using multi-equation models gives free hand at analyzing measurement results because it enables analysis of effects and interaction of many output variables. It also allows analysis of the measurement results during dynamic process. In this paper author presents advantages of using the multidimensional regression model on example of researches conducted on engine test stand.

Abstract: Striving for a perfect imitation of fish motion is one of assumptions of building autonomous biomimetic underwater vehicle. Usage of typical servomechanisms gives good results, but it is important to eliminate their two main disadvantages: large power consumption and constant torque in whole range of motion. In the paper, an analysis of possibilities of using set consisting of a permanent magnet and an induction coil for electromagnetic drive of the vehicle was included. Values of driving torque and character of its change in comparison with muscle system of fish were estimated.