Universität Stuttgart

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Institute: search.filters.UBSInstitut.Institut für Technische und Numerische MechanikAuthor: search.filters.author.Bestle, Dieter

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Now showing 1 - 7 of 7
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    Analyzing and optimizing multibody systems
    (1992) Bestle, Dieter; Eberhard, Peter
    Optimization of holonomic as well as non-holonomic multibody systems is presented as a nonlinear programming problem that can be solved with general-purpose optimization codes. The adjoint variable approach is used for calculating design derivatives of a rather general integral type performance measure with respect to design parameters. The resulting equations are solved by numerical integration backward in time. A multi-step integration algorithm with order and step-size control is adapted for this application by including an interpolation scheme. Numerical experiments and a comparison to the common approach of approximating the gradient of the performance measure by finite differences show that high efficiency, accuracy, and reliability are achievable.
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    An orthogonal complement matrix formulation for constrained multibody systems
    (1994) Blajer, Wojciech; Bestle, Dieter; Schiehlen, Werner
    A method is proposed for the automatic generation of an orthogonal complement matrix to the constraint matrix for the dynamic analysis of constrained multibody systems. The clue for this method lies in the determination of local constraint matrices and their orthogonal complements relative to the local reference frames of particular constrained points. These matrices are then transformed into the system's configuration space in order to form the final constraint matrix and its orthogonal complement. The avoidance of singularities in the formulation is discussed. The method is specially suited for the dynamic analysis of multibody systems with many constraints and/or closed-loops.
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    Automated approach for optimizing dynamic systems
    (1994) Bestle, Dieter; Eberhard, Peter
    The optimal design of nonlinear dynamic systems can be formulated as a multicriteria optimization problem. On the basis of a multibody system model integral type objective functions are defined evaluating the dynamic behavior of the system under consideration. Multicriteria optimization methods reduce the problem to nonlinear programming problems which can be solved with standard algorithms like the SQP method. The gradients required for such an efficient optimization procedure are computed by solving, additional differential equations resulting from an adjoint variable approach. The whole design process can be highly automated by using computer algebra packages.
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    Mehrkriterienoptimierung von Mehrkörpersystemen
    (1994) Eberhard, Peter; Bestle, Dieter
    Mit Strategien wie der Zieloptimierung kann man Konflikte zwischen verschiedenen Gütekriterien erkennen und es läßt sich durch geeignete Wahl der Optimierungsziele für jedes Kriterium ein für den Anwender "optimales" Ergebnis ermitteln. Alle Verfahren sind jedoch nur als wertvolle Hilfsmittel anzusehen, die es ermöglichen, das Wissen über den mehrdimensionalen Kriterienraum zu erweitern. Die Entscheidung für einen bestimmten Entwurf ist und bleibt eine echte Ingenieuraufgabe.
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    Integrated modeling, simulation, and optimization of multibody systems
    (1994) Eberhard, Peter; Bestle, Dieter
    Design of nonlinear dynamic systems is a challenging task. Computers may help to analyze and optimize virtual prototypes in an earl design phase, but there is a lack of design tools. In this paper, a design concept on the basis of a multibody system approach is described. Programs for modeling, simulation, sensitivity analysis, optimization, and animation are operating under a common administration which ensures model consistency. The designer is supported by a graphical user interface, distributed computation improves efficiency.
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    Optimal damping of multi-story buildings under wind excitation
    (1994) Bestle, Dieter; Schiehlen, Werner
    Wind excited vibrations of high-rise buildings can be reduced by installing additional damping devices like tuned mass dampers. The design of tuned mass dampers on different levels of the building is performed via a computer-aided modeling and design approach. A multi body system model is used for describing the dynamic behavior of the structure and the problem of optimizing the parameters of the damping devices is formulated as a nonlinear programming problem. An application to a building of the University of Stuttgart shows that optimal designs with minimal accelerations of the building can easily be obtained.
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    Optimizacija transportnogo sredstva s aktivno upravljaemymi podveskami
    (1993) Bestle, Dieter; Schiehlen, Werner; Eberhard, Peter
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