1 / 40

Nataliya Mulyar Laci Posta

Nataliya Mulyar Laci Posta. C oupling O f M ultidisciplinary M odels. Outline. Introduction: COMM within Bode-RC Rose-RT Simulink Rose-RT and Matlab/Simulink: how to couple? State-of-affairs in COMM. Boderc Project. Consequences of design decisions can be predicted as early as possible

palani
Télécharger la présentation

Nataliya Mulyar Laci Posta

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Nataliya Mulyar Laci Posta CouplingOfMultidisciplinaryModels

  2. Outline • Introduction: COMM within Bode-RC • Rose-RT • Simulink • Rose-RT and Matlab/Simulink: how to couple? • State-of-affairs in COMM

  3. Boderc Project • Consequences of design decisions can be predicted as early as possible • System-level decisions can be analyzed • Trade-offs can be made between functions, price, performance, etc. Goal: improve multi-disciplinary system design, i.e. combining mechanics, electronics and informatics, such that

  4. The COMM project • COMM = Coupling of Multidisciplinary Models • 9- month duo OOTI final project • Started on 1st of December 2003

  5. Problem Description Sequential development  long development cycle Parallel development  lack of communication btw.disciplines  incorrect assumptions  problems during integration  late time-to-market Possible solution:simulate an embedded system in its intended environment

  6. COMM Project Focuses on design of Multidisciplinary Coupling Tool (MCT) Business Case

  7. Concrete Goals • Explore possibilities of coupling of tools used in MD modeling • Use Rose-RT and Matlab/Simulink as a concrete case for coupling • Get better understanding of coupling: • relation simulation-reality • the notion of time in multidisciplinary modeling

  8. Simulation Simulationcontains a set of models of one or more dynamical systems and the interaction between those systems and their environment (Jim Ledin). Model is a physical, mathematical, or other logical representation of a system/process. Simulation advances through time and solves the equations for all models at each point in time.

  9. event 1 event 2 event 3 t1 t2 t3 t4 … t1 t2 t3 Time step Simulation Two basic representation methods of simulation models: • The discrete event simulation, where time is moving forward from one change of state to the next • The time step simulation, where time is divided into intervals

  10. Simulated system environment Rose-RT SW model Matlab/ Simulink physical model MCT Target system SW HW Real vs. Simulated Discrete Discrete and/or continuous Hybrid Simulate the real-time behavior of the embedded system

  11. Set-point generator Controller Motor Encoder + Case Study Motor Control Loop Model • Criteria for case-study selection: • Low level of model complexity • Multidisciplinary aspect: SW + HW components • Interaction btw. SW and HW components

  12. Rose-RT Matlab/ Simulink Set-point generator Controller Motor Encoder + Mapping on Tools Motor Control Loop Model Centralized Software Control

  13. Rose-RT Matlab/ Simulink Set-point generator Controller Motor Encoder + Mapping on Tools Motor Control Loop Model Distributed Software Control Decision 1: select Distributed Software Control

  14. Rose-RT and Matlab/ Simulink Rose-RT Matlab/ Simulink Computing resources 1 PC or 2 PC’s? Decision 2: use a single PC for simulation

  15. Outline • Introduction: COMM within Bode-RC • Rose-RT • Simulink • Rose-RT and Matlab/Simulink: how to couple? • State-of-affairs in COMM

  16. What is Rose-RT? Software development environment for: • Creating UML models using the elements and diagrams defined in the UML • Generating complete code implementations for those models • Executing, testing and debugging models • Uses the extensibility features of the UML for real-time reactive system development

  17. Capsule port S1 Environment S2 Rose-RT from inside • Stereotypes (special form) of class • – Capsules • • Template of active objects • – Protocols • • Template of ports Ports: created and destroyed along with their capsule

  18. Ports Active objects Encapsulation shell

  19. transitionS1toS2: {int x; x = 0; p2.send(s1); p3.send(s2); … }; S1 S1 S2 S3 Capsule: Behavior • Optional hierarchical state machine (signal handler with run-to-completion semantics) S1 S2

  20. Traffic Lights example

  21. Goal: Understand the notion of time in multidisciplinary modeling Timing in Rose-RT

  22. Goal: Understand the notion of time in multidisciplinary modeling Timing in Rose-RT • Time in Rose-RT is strongly connected with the system clock • Precision is dependent on the granularity of the OS • Accuracy is not guaranteed • Timing in Rose-RT is unpredictable • Simulation in Rose-RT can be achieved only by step-by-step execution

  23. Outline • Introduction: COMM within Bode-RC • Rose-RT • Simulink • Rose-RT and Matlab/Simulink: how to couple? • State-of-affairs in COMM

  24. x (states) u (input) y (output) What is Simulink? Simulink is a software package for modeling and simulating dynamic systems process of computing a system’s states and outputs over a span of time, using information provided by the system’s model

  25. y1 (output) x1 (states) x2 (states) u1 (input) u2 (input) y2 (output) Components of a Simulink model • Continuous blocks respond continuously to changing input. • Discrete blocks respond to changes in input only at integer multiples of a fixed interval called the block’s sample time.

  26. Structure of a Simulink model • A typical Simulink model includes sources, systems and sinks. • Simulink provides: • graphical block diagram capability • drag-and-drop blocks facility

  27. Simulink Environment The Library Browser displays a tree-structured view of the Simulink block libraries installed on your system.

  28. Motor model

  29. Components of a Simulink model • Solvers A program, called ordinary differential equation (ODE) solver, updates block inputs and computes block outputs and states at intervals from the simulation start time to the simulation end time.  You can specify the solver to use in the model or when running a simulation.

  30. Goal: Understand the notion of time in multidisciplinary modeling Timing in Matlab/Simulink • The simulation time in Matlab/Simulink and real clock are not the same The amount of time it takes to run a simulation depends on - model complexity, computer’s speed, solver’s type, etc. • Simulation time and real time are not proportional Simulation time can run faster  time acceleration slower  time stretching • Facilities for scheduling and dealing with concurrencyare not offered  is not suitable for simulation of SW

  31. Goal: Understand the notion of time in multidisciplinary modeling TrueTime Real-time kernels and network transmissions can be simulated • Different processing times, priorities, and arbitrary scheduling policies in the computer nodes can be specified • Various network protocols may be evaluated • By introducing disturbing traffic on the network, the effects of unpredictability in the network communication can be studied • Limitations • Code generated by other applications cannot be directly used in TrueTime framework

  32. Outline • Introduction: COMM within Bode-RC • Rose-RT • Simulink • Rose-RT and Matlab/Simulink: how to couple? • State-of-affairs in COMM

  33. ROSE-RT MATLAB/ SIMULINK MCT ROSE-RT MATLAB/ SIMULINK Goal: Explore ways of coupling of tools used in MD modeling Rose-RT and Matlab/Simulink: How to couple? Approach 1 Approach 2 Decision 3: select loosely-coupled architecture

  34. MCT Timing request Timing request Data Data Provide timing Provide timing ROSE-RT MATLAB/ SIMULINK Goal: Explore ways of coupling of tools used in MD modeling Rose-RT and Matlab/Simulink:Where to place timing? • Not feasible due to the timing service of Rose-RT

  35. MCT Timing request Timing request Data Data Provide timing Provide timing ROSE-RT MATLAB/ SIMULINK Goal: Explore ways of coupling of tools used in MD modeling Rose-RT and Matlab/Simulink: Where to place timing? • Timing is enforced to both modeling toolsets • No advantage of Matlab/Simulink timing is taken

  36. MCT Timing request Timing request Data Data Provide timing Provide timing ROSE-RT MATLAB/ SIMULINK Goal: Explore ways of coupling of tools used in MD modeling Rose-RT and Matlab/Simulink: Where to place timing? • Rose-RT timing is not used • Matlab/Simulink provides a well-defined notion of simulation time Decision 4: use Matlab/Simulink as a timing provider

  37. Outline • Introduction: COMM within Bode-RC • Rose-RT • Simulink • Rose-RT and Matlab/Simulink: how to couple? • State-of-affairs in COMM

  38. MCT Design

  39. ToDo • Rose-RT automated step-by-step execution  changes in RTController needed (complex!) • Rose-RT timing compatibility with Simulink replacement of Windows NT Timing Services • Simulation in intended target environment  durations of execution of Rose-RT functions on a target OS should be available

  40. Questions

More Related