SBIR Phase I: An Improved Method for High-Speed Solution of Stiff Problems in Real Time

*9660755 Hannauer这个小企业创新研究第一阶段项目是开发和评估一种有前途的新集成算法，用于实时解决刚性问题。此类问题经常出现在航空航天、化工、核能、电力和汽车应用中。在这种应用中，一种常见的设计技术是将被评估系统部分的计算机模型(通常由常微分方程式组成)与实际系统硬件相结合。这种“硬件在环”应用程序需要实时操作；模拟一秒的系统操作可能不会花费超过一秒的计算机时间。有些模型包含非常快的子系统(例如，机械系统中的“紧”控制器或电气系统中的小寄生阻抗)。如此大的特征值(高频、短时间常数)需要非常短的计算步骤才能稳定。如果计算机不能在这么短的时间内求解整个系统方程组，实时操作是不可能的。提出的积分算法，称为LIMP(线性化隐式)方法，允许对给定系统采取更大的步骤，使许多以前难以解决的问题能够实时解决。潜在的商业应用包括飞机、导弹、化学反应堆、发电机和汽车的设计。***

*** 9660755 Hannauer This Small Business Innovation Research Phase I project is to develop and evaluate a promising new integration algorithm for solving stiff problems in real time. Such problems occur frequently in Aerospace, Chemical, Nuclear, Electric Power, and Automotive applications. In such applications, a common design technique is to combine a computer model of part of the system under evaluation (usually consisting of ordinary differential equations) with actual system hardware. Such "hardware in the loop" applications require real-time operation; the simulation of one second of system operation may take no more than one second of computer time. Some models contain very fast subsystems (e.g. a "tight" controller in a mechanical system or a small parasitic impedance in an electrical system). Such large eigenvalues (high frequencies, short time constants) require a very short computational step for stability. If the computer can't solve the entire set of system equations in this short time, real-time operation is impossible. The proposed integration algorithm, called the LIMP (Linearized IMPlicit) method, allows much larger steps to be taken for a given system, enabling real-time solution of many previously "intractable" problems. Potential commercial applications include the design of aircraft, missiles, chemical reactors, power generators, and automobiles. ***