l'analisi multibody nell industria automotive: Adams/Car Paolo Gervasio MSC.Software Project Manager Mercoledì 30 aprile 2014
Agenda ADAMS: Automatic Dynamic Analysis of Multibody System Presentazione di Adams quale solutore di sistemi multicorpo, I diversi software della suite Adams e la loro integrazione in Adams/Car. Adams/Car Perché A/Car e sua struttura. Organizzazione dei dati e realizzazione dei modelli utente mediante il sistema template->subsytem->assembly. Simulazioni con A/Car Tipologie di simulazioni affrontabili con Adams/Car, peculiarità e ambito di applicazione. Realizzazione di nuovi modelli Il template builder e la creazione di modelli parametrici. SmartDriver Il pilota di A/Car, dove interviene e suo utilizzo. Adams/Tire Modelli di pneumatico disponibili in A/Car, cosa sapere per un uso corretto. Adams/Controls Cosimulazione in ambiente Adams/Car Adams/Flex Introduzione di corpi deformabili in un modello Adams.
Introduzione alla dinamica dei sistemi multi-body Definizione di sistema Multi-Body Sistema di parti meccaniche rigide / flessibili Interconnesse da giunti rigidi / elastici Soggette a qualsiasi sistema di forze Compiono grandi spostamenti nello spazio 3D
Introduzione alla dinamica dei sistemi multi-body Definizione di sistema Multi-Body Dinamica descritta da equazioni differenziali Vincoli descritti da equazioni algebriche Sistema di equazioni DAE non-lineare Risoluzione di tipo numerico Integratori ODE (Ordinary Differential Equations) Integratori DAE (Differential Algebraic Equations)
Introduzione alla dinamica dei sistemi multi-body Basic Concepts
Introduzione alla dinamica dei sistemi multi-body Kinematics: Basic Concepts o Study of motion of a system without regard to motivating forces o All degrees of freedom are prescribed as functions of time o Forces cannot affect motion o Forces calculated as a consequence of motion o Displacement, Velocity, Acceleration and Reaction force solution is algebraic in nature o No need to solve differential equations Statics: o Study of equilibria of a system without regard to inertia forces or velocity dependent forces o System velocities and accelerations are zero at each configuration o Force affects configuration only o Governing equations are algebraic in nature Dynamics: o Study of motion of a system as a consequence of applied forces and inertia forces o Forces affect accelerations o Accelerations are integrated to velocities o Velocities are interated to give displacements o 2nd order differential equations are to be solved Linear Analysis: o Study of the modes of vibration of a system at any specified operating point: o Equations of motion are linearized about operating point to getare constant matrices o Vibration mode shapes and frequencies are analyzed by solving the associated eigenvalue problem
Introduzione alla dinamica dei sistemi multi-body ADAMS Automated Dynamic Analysis of Mechanical System GENERAL PURPOSE COMPUTER PROGRAM
Applicazioni dell Analisi Multibody
Applicazioni dell Analisi Multibody ADAMS/Controls ADAMS/Durability ADAMS/Flex ADAMS/Linear ADAMS/Postprocessor ADAMS/Insight ADAMS Full Simulation ADAMS/View(Pre/Post) & ADAMS/Solver ADAMS/Exchange
Applicazioni dell Analisi Multibody nella grande industria Bridges departments by sharing models and data Facilitates quick subsystem changes Templates Test lab Engine Advanced Engineering Suppliers Driveline Chassis engineering Body engineering
Applicazioni dell Analisi Multibody nella grande industria ADAMS/Controls ADAMS/Durability ADAMS/Flex ADAMS/Linear ADAMS/Postprocessor ADAMS/Insight ADAMS Full Simulation ADAMS/View(Pre/Post) & ADAMS/Solver ADAMS/Exchange
Adams/Car
Adams/Car: gerarchia dei modelli
Adams/Car: organizzazione dei dati A database is a collection of tables (directories) stored on the hard drive. The top directory, which has the extension.cdb, stores a number of tables (directories). Each table is a placeholder for model information.
Adams/Car: file di simulazione Adams/Car Interface Driver control data file (.dcd) Event file (.xml) Adams command file (.acf) Adams dataset file (.adm) Adams/Car Solver.msg.req.res Output files.gra.out
Adams/Car: tipologie di simulazione
Adams/Car: tipologie di simulazione
Adams/Car: Template builder
Adams/SmartDriver 1. Calcola con un solutore quasistatico un profilo di velocità coerente con la traiettoria e i limiti del veicolo 2. Il solutore interno (modello rigido semplificato) verifica l applicabilità della velocità richiesta in quel punto di simulazione e ne richiede la eventuale correzione 3. Il veicolo viene risolto nelle condizioni previste con il modello semplificato
Adams/Tire
Adams/Tire
Adams/Controls (Co-simulation)
Adams/Controls (Function evaluation) Function evaluation (or continuous) mode lets the MATLAB (or EASY5) integrators solve the entire problem made up of the Adams equations and the MATLAB (EASY5) equations. In this mode, Adams simply acts as a function evaluator for the MATLAB (EASY5) integrator. Mode Integrators used Comments Co-simulation MATLAB and Adams MATLAB solves Simulink model, Adams/Solver solves Adams model. Data exchanged periodically. Function Evaluation MATLAB MATLAB solves both, Simulink model and Adams model. Adams/Solver just acts as function evaluator for MATLAB integrator.
Adams/Controls (Control system import) If you can satisfy these requirements: 1. MATLAB with a Real Time Workshop license available. 2. Microsoft Visual C++ for compilation in RTW. Other C/C++ compilers (for example gcc) will not work properly. 3. An available Adams/Controls license. *.dll
Adams/Controls (FMI Co-simulation) Adams will support the Functional Mock-up Interface (FMI) standard
Adams/Flex: Component Mode Synthesis free-free mode static correction mode
Adams/Flex: Coupling Equation of Motion Use Lagrangian Formulation: The Flexible Body Extended DOF table ξ Rigid Modal 1. Compute position of point P in Global Ref. 2. Use Modal Expansion approximation for u p u p Σ Φ i (P)q i 3. Derive w.r.t. time and compute v p 4. Compute Kinetic and Potential Energy for the FB 5. Solve Equations
Adams/Flex
MSC & University
MSC Student Editions MSC Nastran Student Edition (with Patran) FEA Solver Used by Large Manufacturers MSC Nastran-Patran Marc Student Edition (with Mentat) FEA Solver for Tough Nonlinear Problems Marc-Mentat Adams Student Edition (with View) Kinematic and Dynamic Analysis of Systems Actran Student Edition Adams-View Powerful Acoustic Simulation Software Actran
Learning Resources for Teachers
Learning Resources for Students MSC Learning Center - $99 Subscription for Students Video Tutorials Student Edition Tutorials Actran Student Edition Tutorials Problem Sets SimCompanion Knowledge Base Portal 32
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