基于键合图法的活塞泵建模与仿真

基于由荷兰Twente大学控制工程系研发的机电一体化建模软件20-sim,提出利用键合图法实现活塞泵的建模与仿真。在实例模型中,首先实现了单向阀的20-sim模块构造,继而在20-sim环境中建立了活塞泵的键合图模型,仿真结果理想地显示了概念设计阶段的控制效果。     

模型参考自适应控制的20-sim软件实现

简要地介绍了李雅普诺夫稳定意义上模型参考自适应控制（MRAC）的基本原理,给出了设计MRAC控制系统的基本步骤。基于荷兰Twente大学控制工程系研发的机电一体化设计软件20-sim,以Twente大学先进控制演示仪为研究对象,在20-sim下建立了系统的图标化数学模型,编制了模型参考自适应和Lyapunov求解模块。在此基础上,构成了完整的MRAC控制系统。仿真结果显示基于20-sim建模与仿真方法直观简便,所设计的模块可移植性强,为控制系统的建模与仿真提供了新的思路。     

卡尔曼滤波器的20-sim软件实现

简要地介绍了线性二次型高斯(linear quardratic gauss,LQG)控制的基本原理,即利用卡尔曼滤波器估计未知状态变量,实现多变量系统的最优状态反馈控制.基于荷兰Twente大学控制工程系研发的机电一体化设计软件20-sim,编制了卡尔曼滤波器和最优状态反馈模块.在实例模型中,首先利用20-sim建立了控制系统图标化模型.在此基础上,应用了最优状态反馈控制和卡尔曼滤波器模块,构成了完整的LOG控制系统.仿真结果理想的显示了控制效果.由此可见,基于20-sim建模与仿真方法直观简便,为控制系统的建模与仿真提供了新的思路.     

基于系统辨识的模型参考自适应控制

介绍了荷兰Twente大学控制工程系研发的先进控制实验平台的基本组成、功能和基于机电一体化设计软件20-sim。以先进控制演示仪为研究对象,在20-sim环境下建立了系统的图标化数学模型,并从理论上对模型作了降阶分析。根据系统辨识的模型参考自适应控制（MRAC）原理,编制了模型参考自适应和Lyapunov求解模块。采用线性二次型调节器为控制模块,构成了完整的先进控制演示仪的MRAC控制系统。该系统仿真结果显示所建立的模型针对性强,可用于各种先进控制策略的仿真研究。     

基于伪键合图法的电磁泵建模与仿真

采用由荷兰Twente大学研发的机电一体化建模软件20-sim,用键合图法模拟并实现了电磁泵中磁场域、电场域和液压域的相互作用过程,仿真分析了电磁泵的进出水状况.根据电磁泵在工作过程中泵室的发热情况,利用伪键合图法对电磁泵中的热力系统进行了分析和仿真,结果显示了电磁泵系统的热力学性能和动态特征.在分析电磁泵进出水时纹波产生原因的基础上,通过调节参数消除了纹波的影响.总体仿真结果反映了在设计阶段的20-sim建模环境中利用伪键合图法建模的直观效果.     

V850E/MS1嵌入式处理器的实现

针对嵌入式系统软件的开发效率问题,通过对V850E/MS1体系结构建模研究,提出并实现一个高效的指令集模拟器V850E/MS1- sim,该模拟器主要由指令集系统、内存管理、终端系统和外设接口组成,采用指令集模拟和串行模拟的方法。仿真实验结果表明,V850E/MS1-sim在保证模拟精确性的同时,提高了模拟效率。     

基于SHML的CPS行为建模及仿真

信息物理融合系统（cyber-physical systems，简称CPS）是深度融合了计算进程和物理进程的统一体，是集计算、通信与控制于一体的下一代智能系统，具有广阔的应用前景.CPS的行为具有混成性、随机性等特征，建模及仿真CPS的动态行为对于开发高质量的CPS系统至关重要.但是目前缺乏面向CPS的领域建模方法及建模CPS的领域建模语言，也迫切需要支持仿真CPS领域模型的仿真工具.针对以上问题，提出一种面向CPS领域的随机混成建模语言（stochastic hybrid modeling language，简称SHML）以支持建模CPS系统的行为.首先，根据CPS的领域特征定义了SHML的元模型作为其抽象语法，并定义了SHML的具体语法和操作语义；其次，基于GEMOC框架实现了SHML的可视化建模工具.此外，集成GEMOC的序列化执行引擎和Scilab的连续行为仿真引擎，实现仿真CPS的混成行为.提出了一种面向CPS领域的建模及仿真方法，设计并实现了一个集成的面向CPS行为的建模与仿真平台，为CPS的建模及仿真提供了一种有效的方法及工具支撑.     

Use of MATLAB and 20-sim to simulate a flash separator

This work presents the simulation of a two-phase flash separator, one of the processes of an industrial natural gas liquefaction plant. The model simulated was developed using the bond graph methodology, and MATLAB and 20-sim software were used to obtain the dynamic behavior of the flash. MATLAB was used to determine the input conditions of the separator as they were not provided by the plant information, and 20-sim was used to simulate the bond graph model. The simulation results were validated using real operating conditions of the plant. The paper shows how this two widely used computer programs can help in the understanding of the behavior of real process.     

20-sim与Matlab交互实现倒立摆系统的稳定性分析

本文简要介绍了20-sim软件的主要功能、编程环境和仿真方法。在讨论倒立摆系统是自动控制理论专业的理想实验对象的基础上,介绍了一阶倒立摆系统的构成和数学模型,提出利用20-sim软件对倒立摆系统的稳定性进行判断,在此基础上,应用自动控制技术中的最优状态反馈控制,利用SIDOPS＋仿真语言将20-sim与Matlab相结合进行仿真,理想地显示了控制效果。     

基于20-sim软件的非线性电路仿真

利用20-sim软件的功能,可以对非线性电路进行直接面向方程的仿真分析,也可以在现有非线性电路的基础上,转换成相应的键合图模型,利用键合图理论进行仿真分析.为了对这两种仿真分析方法进行对比分析,选取杜芬方程作为研究对象,提出了运算放大器的键合图模型,分别用图形化的方法与键合图方法进行了仿真,并对两种方法进行了结论性的比较.     

HSWAP:适用于高性能计算环境的数值模拟工作流管理平台

针对高性能计算（HPC）环境中的"建模、计算、分析、优化"一体化应用构建的问题，设计了支持数值模拟软件封装和数值模拟工作流交互设计的数值模拟工作流管理平台——HSWAP。首先，基于对数值模拟活动的运行特征共性建模构建组件模型；然后，利用工作流表达数值模拟活动间的控制、数据依赖关系，建立形式化的数值模拟工作流模型，所形成的工作流模型可在平台中自动解析并适配高性能计算资源，从而实现批量关联数值模拟任务的自动生成与调度，为领域用户屏蔽高性能计算资源的使用细节。平台提供Web Portal服务，支持图形数值模拟程序的交互界面推送。目前该平台已在超算中心实际生产环境得到部署应用，可在2人月内完成包含10个以下数值模拟软件、20个以内计算任务节点的数值模拟工作流的集成。     

矿用电动轮车交流传动系统的建模与仿真

矿用电动轮自卸车的交流传动系统是一个复杂的多能域系统,主要由功率变换器和电机组成。采用可调变换器附加导通电阻Ron的方式建立功率变化器开关器件的键合图模型,并以其为基本部件建立功率变换器的键合图模型。根据其建立的模型在所有开关模式下具有同样的因果关系,不需要因为系统模式的变化而重新指派计算因果关系。根据d-q坐标系下电机的等效电路图建立电机的键合图模型,并由键合图模型推导出电机的状态方程。采用MTLAB/Simulink和20-sim软件对功率变换器和电机的键合图模型分别进行仿真,实验结果验证了模型的正确性,说明键合图理论能够用于复杂多能域系统的统一建模。     

Simulating simulation-agnostic SysML models for enterprise information systems via DEVS

Systems Modeling Language (SysML) is used as the modeling infrastructure in systems engineering, especially for complex systems design, independently of the system domain. Simulation is a common method to perform system model verification, during the systems development process. However, simulation code generation and execution is not integrated within the system design activity, as it is facilitated by SysML. It is either conducted as an external activity, after system design, or it affects the system design environment and practices, according to specific simulators requirements.This paper presents how existing, simulation-agnostic SysML models from the domain of Enterprise Information System (EISs), can be transformed to executable simulation code and in addition how the simulation results can be incorporated into the source SysML model through the exploitation of Model Driven Architecture (MDA) principles and techniques. To this end, several tools and technologies are utilized, while the verification process is triggered and finalized via the system modeling environment. Adoption of MDA provides a solid, high-level infrastructure and tool availability to the proposed approach.     

陈述式基于方程仿真模型的约简

为解决复杂多领域连续系统的高效仿真问题,研究了陈述式基于方程仿真模型的约简策略.基于符号处理技术,提出了一种模型约简方法.该方法从方程的规范转换入手,通过消除特定形式方程缩减系统规模,将整个方程系统规划分解为一个可顺序求解的子系统序列.给出的实例表明文中约简方法效果显著.文中策略与算法已在多领域物理系统混合建模与仿真平台EMWorks中实现.     

基于键合图的汽车悬架系统建模与仿真

键合图是一种图形工具,它可以清晰形象地描述系统内部的能量结构.文中给出了功率键合图理论对汽车1/4、1/2悬架系统建模的详细方法,建立了1/4、1/2悬架的键合图模型.对1/2悬架键合图模型进行仿真时,文中没有采用传统的推导状态方程方法,而是将键合图模型按照键合图与方块图的转化关系直接转为方块图模型,再利用MATLAB软件的Simulink工具箱对1/2悬架的方块图进行建模仿真.给出了仿真模型,得到了较好的仿真结果.验证了键合图结合方块图理论对系统建模和分析的优越性.     

A scalable multiscale LATIN method adapted to nonsmooth discrete media

The simulation of discrete systems often leads to large scale problems, for instance if they result of a discretization technique, or a modeling at a small scale.A multiscale analysis may involve an homogenized macroscopic problem, as well as a coarse space mechanism to accelerate convergence of the numerical scheme. A multilevel domain decomposition technique is used herein as both a numerical strategy to simulate the behaviour of a non smooth discrete media, and to provide a macroscopic numerical behaviour of the same system.Several generic formulations for such systems are discussed in this article. A multilevel domain decomposition is tested and several choices of the embedded coarse space are discussed, in particular with respect of the emergence of weak interfaces, characteristics of the discrete media substructuration. The application problem is the quasi-static simulation of a large scale tensegrity grid.     

IMPROVEMENTS IN THE SYSTEMS-BASED MODELS GENERATOR SIGEM

Program generators, for us, are computer programs that produce other computer programs. SIGEM is an expert system program generator that can help in the modeling process of real systems. It is associated with a methodology well adapted to modeling practice. In this paper, we present and compare this methodology with other similar ones. Static models (databases), dynamic models, rule-based expert systems, literal and/or numerical variables, probabilistic uncertainty in data and in functions, dimensioned variables, discrete event simulation, and other related problems can be treated with this methodology. We suggest a systems modeling methodology and a programming tool to increase generality of application and easiness of use.     

Construction method of shop-floor digital twin based on MBSE

Digital twin (DT) technology is essential for achieving the fusion of virtual-real cyber-physical systems. Academics and companies have made great strides in the theoretical research and case studies of constructing the shop-floor digital twin (SDT), which is the premise of applying DT technology on the shop floor. A shop floor is a large complex system that involves many elements including people, machines, materials, methods, and the environment and processes, such as the technical flow, business process, logistics, and control flow. However, most of the developed cases lack a hierarchical, structured and modularized implementation framework for the development of an SDT system, which leads to problems such as a low reuse rate of the system blocks, lack of scalability, and high upgrade and maintenance costs. In response to these issues, we propose a construction method of the DT for the shop floor based on model-based systems engineering from the perspective of the system. In this method, a comprehensive DT model for the shop floor is gradually constructed by using system modeling language, the modeling method “MagicGrid,” and the “V model” of systems engineering. The model includes four dimensions of the shop-floor requirements, structure, behavior, and parameters, as well as three stages (the problem domain, solution domain, and implementation domain), and connects nine steps of the “V model,” including the system requirements, system architecture, subsystem implementation, subsystem integration, and system verification. Then, based on an example of a real NC machining shop floor, subsystems including a visualization system, synchronization system, and simulation system, are discussed. Finally, the functions of the integrated systems are verified based on the requirements, including the real-time synchronization of “man, machine, material, and method” and the transient simulation in real time. The numerical indicators of the integrated system are verified, including the model completeness and synchronization timeliness.     

A model-based computer-aided prototyping system

Computer aided prototyping systems which allow application domain experts to compose prototypes using domain specific components, semantics, and primitives can reduce the time and effort needed for prototyping considerably.The notion of domain model is introduced as a vehicle for defining, generating, and categorizing domain specific components. Facilities to compose the components generated from the domain model to implement complex functionality are presented.A rapid prototyping system which provides a domain modeling tool and a visual direct manipulation composition tool is described. The main element of the domain modeling tool is a domain modeling language which provides: (i) a class construct to define object, (ii) rule, trigger, event, and relationship constructs to define interactions among objects, and (iii) process, task, and signal constructs to define the activities in the domain.The composition tool is the extension of a visual tool called IntelligentPad (IP) which supports unified data and control flows through a simple paste and connect metaphor. Domain models are translated to generate components, which are then composed using the extended IP.