Model-Based Systems Engineering Approach to Distributed and Hybrid Simulation Systems

INCOSE defines Model-Based Systems Engineering (MBSE) as the formalized application of modeling to support system requirements, design, analysis, verification, and validation activities beginning in the conceptual design phase and continuing throughout development and later life cycle phases. One very important development is the utilization of MBSE to develop distributed and hybrid (discrete-continuous) simulation modeling systems. MBSE can help to describe the systems to be modeled and help make the right decisions and partitions to tame complexity. The ability to embrace conceptual modeling and interoperability techniques during systems specification and design presents a great advantage in distributed and hybrid simulation systems development efforts. Our research is aimed at the definition of a methodological framework that uses MBSE languages, methods and tools for the development of these simulation systems. A model-based composition approach is defined at the initial steps to identify distributed systems interoperability requirements and hybrid simulation systems characteristics. Guidelines are developed to adopt simulation interoperability standards and conceptual modeling techniques using MBSE methods and tools. Domain specific system complexity and behavior can be captured with model-based approaches during the system architecture and functional design requirements definition. MBSE can allow simulation engineers to formally model different aspects of a problem ranging from architectures to corresponding behavioral analysis, to functional decompositions and user requirements (Jobe, 2008)

An XML Application-Based Interface to Developing Modular System Simulations

We introduce a framework for the development of modular lumped and distributed parameter system models, the latter described by boundary value problems. The simulation of such systems requires careful analysis and a rigorous approach to development to provide both accuracy and computational efficiency. We explain the current implementation, which solves such systems in a MATLAB environment using object-oriented programming principles as part of the Modular Distributed Parameter System Analysis and Simulation (MDPSAS) package. We propose a mechanism for creating user-defined simulation elements using a web-based collaborative interface. The creation of a novel semantic vocabulary built into an XML application language called ModSimML is presented as a tool for data structuring and exchange. The development of a schema for the XML application formalizes of our data model. The utility of this interface is described via an application to research in Biological Micro-Electro-Mechanical Systems (BioMEMS), whose simulations require assembly from modular components.Advisor: Dr. Ray Adomaitis Institute for Systems Research and Department of Chemical Engineerin

StarL: Toward a web interface for distributed robotics

Most first-time users find it complicated to use the StarL programming framework, especially when they have little experience with Java. The major challenges for programming distributed robotic applications are (1) the learning curve for Java, (2) setting up the StarL development environment, and (3) learning curve for effectively using the Java functions in StarL. We therefore introduce the StarL web interface that provides a more user-friendly access to the StarL programming framework while emphasizing more on the StarL high-level coordination of distributed robots. The StarL web interface enables researchers to implement their applications on distributed robots in the StarL high-level language, run the project and then plot the experiment data for analyzing the robot's traces. The main contribution of this thesis is the user-friendly interface with syntax highlighting and data visualization of the robots' traces obtained through simulation. A Formation example application will illustrate the many aspects of the StarL web interface.Ope

Simulation System for the Wendelstein 7-X Safety Control System

The Wendelstein 7-X (W7-X) Safety Instrumented System (SIS) ensures personal safety and investment protection. The development and implementation of the SIS are based on the international safety standard for the process industry sector, IEC 61511. The SIS exhibits a distributed and hierarchical organized architecture consisting of a central Safety System (cSS) on the top and many local Safety Systems (lSS) at the bottom. Each technical component or diagnostic system potentially hazardous for the staff or for the device is equipped with an lSS. The cSS is part of the central control system of W7-X. Whereas the lSSs are responsible for the safety of each individual component, the cSS ensures safety of the whole W7-X device. For every operation phase of the W7-X experiment hard- and software updates for the SIS are mandatory. New components with additional lSS functionality and additional safety signals have to be integrated. Already established safety functions must be adapted and new safety functions have to be integrated into the cSS. Finally, the safety programs of the central and local safety systems have to be verified for every development stage and validated against the safety requirement specification. This contribution focuses on the application of a model based simulation system for the whole SIS of W7-X. A brief introduction into the development process of the SIS and its technical realization will be give followed by a description of the design and implementation of the SIS simulation system using the framework SIMIT (Siemens). Finally, first application experiences of this simulation system for the preparation of the SIS for the upcoming operation phase OP 1.2b of W7-X will be discussed

Worldsens: development and prototyping tools for application specific wireless sensors networks

International audienceIn this paper we present Worldsens, an integrated environment for development and rapid prototyping of wireless sensor network applications. Our environment relies on software simulation to help the designer during the whole development process. The refinement is done starting from the high level design choices down to the target code implementation, debug and performance analysis. In the early stages of the design, high level parameters, like for example the node sleep and activity periods, can be tuned using WS-Net, an event driven wireless network simulator. WSNet uses models for applications, protocols and radio medium communication with a parameterized accuracy. The second step of the sensor network application design takes place after the hardware implementation choices. This second step relies on the WSim cycle accurate hardware platform simulator. WSim is used to debug the application using the real target binary code. Precise performance evaluation, including real-time analysis at the interrupt level, are made possible at this low simulation level. WSim can be connected to WSNet, in place of the application and protocol models used during the high level simulation to achieve a full distributed application simulation. WSNet and WSNet+WSim allow a continuous refinement from high level estimations down to low level real-time validation. We illustrate the complete application design process using a real life demonstrator that implements a hello protocol for dynamic neighborhood discovery in a wireless sensor network environment

Generation of feasible deployment configuration alternatives for Data Distribution Service based systems

Data distribution service (DDS) has been defined by the OMG to provide a standard data-centric publish-subscribe programming model and specification for distributed systems. DDS has been applied for the development of high performance distributed systems such as in the defense, finance, automotive, and simulation domains. To support the analysis and design of a DDS-based distributed system, the OMG has proposed the DDS UML Profile. A DDS-based system usually consists of multiple participant applications each of which has different responsibilities in the system. These participants can be allocated in different ways to the available resources, which leads to different configuration alternatives. Usually, each configuration alternative will perform differently with respect to the execution and communication cost of the overall system. In general, the deployment configuration is selected manually based on expert knowledge. This approach is suitable for small to medium scale applications but for larger applications this is not tractable. In this paper, we provide a systematic approach for deriving feasible deployment alternatives based on the application design and the available physical resources. The application design includes the design for DDS topics, publishers and subscribers. For supporting the application design, we propose a DDS UML profile. Based on the application design and the physical resources, the feasible deployment alternatives can be algorithmically derived and automatically generated using the developed tools. We illustrate the approach for deriving feasible deployment alternatives of smart city parking system