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1
Content available Przegląd modeli rozwiązania problemu głównego balistyki wewnętrznej
Kagankiewicz Filip, Magier Mariusz
Problemy Techniki Uzbrojenia
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2023
|
R. 52, z. 163
7--25
PL
Współcześnie większość procesów projektowych odbywa się poprzez wyspecjalizowane narzędzia w postaci zaawansowanego oprogramowania komputerowego, jednak w przypadku balistyki wewnętrznej nie jest ono ogólnodostępne lub jest wręcz utajnione. Z innej strony rzecz ujmując, analityczne rozwiązanie układu nieliniowych równań różniczkowych, opisujących fazy zjawiska strzału w broni lufowej nie istnieje. Dlatego w celu uzyskania dokładniejszych rozwiązań układu równań warto wykorzystać metody numeryczne. W pracy przedstawiono opis teoretyczny zagadnienia na podstawie przeglądu modeli analitycznych i numerycznych rozwiązania problemu głównego balistyki wewnętrznej. Na podstawie tej analizy przyjęto, że możliwym kierunkiem rozwoju jest zaimplementowanie kilku modeli rozwiązania problemu głównego balistyki wewnętrznej w ujęciu numerycznym tak, by użytkownik końcowy (projektant) miał możliwość wyboru różnych modeli i sprawdzenia, który model sprawdza się najlepiej w jego warunkach. Dodatkowo, korzystając z technik optymalizacyjnych, można podjąć próbę implementacji algorytmów, które potrafiłyby poszukiwać np. najmniejszej wartości naważki prochowej przy określonych parametrach prochowych i zadanym ciśnieniu maksymalnym i prędkości wylotowej pocisku. Celem utylitarnym dalszych prac badawczych jest stworzenie nowego narzędzia analitycznego wspomagającego projektowanie broni lufowych.
EN
Nowadays, most design processes are computer-aided, but in the case of internal ballistics they are not generally available or are highly specialized and secret. On the other hand, an analytical solution of the system of nonlinear differential equations describing the phases of the phenomenon of a shot in a gun barrel does not exist. Therefore, in order to obtain more accurate solutions to the system of equations, it is worth to use numerical methods. The paper presents a theoretical description of the problem based on a review of analytical and numerical models solving the main problem of internal ballistics. Based on this analysis, it was assumed that a possible direction of development is to implement several models to solve the main problem of internal ballistics in numerical solution, so that the end user (designer) can choose different models and check which model works best in his conditions. In addition, using optimization techniques, an attempt can be made to implement algorithms that would be able to search for example, the smallest powder weight value at specific powder parameters and at given maximum pressure and projectile muzzle velocity. The utilitarian goal of further research is to create a new analytical tool supporting the design of barrel weapons.
2
Content available Comparison of long time simulation of Hamilton and Lagrange geometry dynamical models of a multibody system
Bai Long, Ge Xinsheng, Xia Lili
Journal of Theoretical and Applied Mechanics
|
2022
|
Vol. 60 nr 4
687--704
EN
The geometry dynamical modeling method for a double pendulum is explored with the Lie group and a double spherical space method. Four types of Lagrange equations are built for relative and absolute motion with the above two geometry methods, which are then used to explore the influence of different expressions for motion on the dynamic modeling and computations. With Legendre transformation, the Lagrange equations are transformed to Hamilton ones which are dynamical models greatly reduced. The models are solved by the same numerical method. The simulation results show that they are better for the relative group than for the absolute one in long time simulation with the same numerical computations. The Lie group based result is better than the double spherical space one.
3
Content available Application of Smoothed Particle Hydrodynamics Method in Metal Processing: An Overview
Nguyen Trang Thi Thu, Hojny Marcin
Archives of Foundry Engineering
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2022
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Vol. 22, iss. 3
67--80
EN
Smoothed Particle Hydrodynamics (SPH) is a Lagrangian formula-based non-grid computational method for simulating fluid flows, solid deformation, and fluid structured systems. SPH is a method widely applied in many fields of science and engineering, especially in the field of materials science. It solves complex physical deformation and flow problems. This paper provides a basic overview of the application of the SPH method in metal processing. This is a very useful simulation method for reconstructing flow patterns, solidification, and predicting defects, limitations, or material destruction that occur during deformation. The main purpose of this review article is to give readers better understanding of the SPH method and show its strengths and weaknesses. Studying and promoting the advantages and overcoming the shortcomings of the SPH method will help making great strides in simulation modeling techniques. It can be effectively applied in training as well as for industrial purposes.
4
Content available Design, construction and control of a spherical rolling robot with internal two-wheel cart
Firlej S.
Automatyka / Automatics
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2015
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Vol. 19, no. 2
63--77
EN
This elaboration presents a spherical rolling robot with a 2-wheel cart. The custom design of the hardware and control software is presented to demonstrate the solution. The robot was started to realize an autonomous task. The embedded robot control system is based on a 32-bit microcontroller and uses a Bluetooth module for wireless communication. The simplified model has been proposed and its parameters identified. The results obtained at the simulation and experimental stages are shown and compared. Finally, the robot’s motion was recorded and analyzed with the support of image signal processing techniques.
PL
W artykule przedstawiony został opis sferycznego robota mobilnego z napędem w postaci dwukołowego wózka. Praca prezentuje dedykowany układ mechaniczny, elektroniczny oraz oprogramowanie sterujące. System wbudowany robota jest oparty na 32-bitowym mikrokontrolerze oraz wykorzystuje bezprzewodową komunikację Bluetooth. Parametry uproszczonego modelu matematycznego robota sferycznego zostały zidentyfikowane, a wyniki symulacji porównano do rezultatów rzeczywistych eksperymentów. Analiza obrazu zarejestrowanego za pomocą zewnętrznej kamery pozwoliła na obserwacje trajektorii ruchu robota.
5
Content available Average case analysis of the set packing problem
Szkatuła K.
Control and Cybernetics
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2014
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Vol. 43, no. 4
557--575
EN
The paper deals with the well known set packing problem and its special case, when the number of subsets is maximized. It is assumed that some of the problem coefficients are realizations of mutually independent random variables. Average case (i.e. asymptotical probabilistic) properties of selected problem characteristics are investigated for the variety of possible instances of the problem.
6
Content available Lagrange and practical stability criteria for dynamical systems with nonlinear perturbations
Krumov A. V.
Archives of Control Sciences
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2012
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Vol. 22, no. 1
43-58
EN
In the paper two classes of nonlinear dynamical system with perturbations are considered. The sufficient conditions for robust Lagrange and practical stability are proven with theorems, applying the theory of nonlinear operators of the functional analysis. The presented criteria give also the bounds of the analyzed dynamical processes. Three examples comparing the numerical computer solutions and the analytical investigation of the stability of the systems are given. The method can be applied to analytical and computer modeling of nonlinear dynamical systems, synthesis of computer control and optimization.
7
Content available remote Comprehensive mathematicaI modelling of a transversely vibrating flexible link robot manipulator carrying a tip payload
Loudini M., Boukhetala D., Tadjine M.
International Journal of Applied Mechanics and Engineering
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2007
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Vol. 12, no 1
67-83
EN
The purpose of this paper is to describe the application of the Timoshenko beam theory (TBT) to the mathematical modelling of a planar one link flexible robot manipulator pinned at its actuated base and carrying a payload at its free end-point. The emphasis has been put on obtaining accurate and complete equations of motion that display the most relevant aspects of structural propenies inherent to the modelled lightweight flexible link. So, in addition to the classical effects of shearing and rotational inertia of the link cross-section, two imponant damping mechanisms: external viscous air damping and internal structural viscoelasticity effect (Kelvin-Voigt damping) have been included. Gravity, torsion, and longitudinal elongation have been neglected. Numerical simulations, performed to show the free vibrational behaviour of the modelled system, demonstrate the imponant effect of the carried payload on the amplitude and the frequency of vibrations.
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