A Rigorous Modeling and Simulation Package for Hybrid Systems

9361232泰勒现有的商业建模和仿真软件包不能充分预测当今正在开发和部署的复杂计算机控制系统的行为。这些“混合”系统涉及不连续的现象，如机械部件接合和脱离(例如，航天器对接)、控制单元切换和软件组件重新配置。不幸的是，这些影响的处理不准确，有时甚至完全忽略了。最近对非线性系统的研究表明，在许多情况下，这种缺陷是表明系统将按要求运行的主要障碍，或者相反，新设计的系统可能存在安全关键缺陷。例如，混合系统可能倾向于振荡或混沌行为(看似随机运动)，模拟器将无法及时预测这些问题，以避免代价高昂的事故或重新设计。在第一阶段，我们建议开发一种严格的建模语言来表示这种现象，并开发集成算法来完全准确地模拟不连续的非线性混合系统。该语言将根据现代标准开发，以促进正确的建模实践。积分算法将严格捕获并处理所有不连续事件。商业套餐将在第二和第三阶段制作。*

9361232 Taylor Existing commercial modeling and simulation software packages do not adequately predict the behavior of complex computer- controlled systems being developed and fielded today. These "hybrid" systems involve discontinuous phenomena such as mechanical parts engaging and disengaging (e.g., spacecraft docking), control units switching, and software components reconfiguring. Unfortunately, these effects are handled inaccurately and sometimes even missed completely. Recent research in nonlinear systems has revealed that there are many circumstances where this deficiency presents a major barrier to showing that a system will perform as required, or conversely that a newly designed system may have safety-critical defects. For example, a hybrid system may be prone to oscillation or to chaotic behavior (seemingly random motion) and the simulator will not be able to predict these problems in time to avoid costly accidents or redesign. We propose in Phase I to develop both a rigorous modeling language for representing such phenomena, and integration algorithms that will simulate discontinuous nonlinear hybrid systems with complete accuracy. The language will be developed according to modern standards, to facilitate correct modeling practices. The integration algorithms will rigorously catch and hand all discontinuous events. A commercial package will be produced in Phases II and III. ***