US-Egypt Cooperative Research: Application of the Saturation- Based Controller to Self-Excited Oscillators and Systems with Limited Energy Sources

美埃合作研究：基于饱和的控制器在自激振荡器和有限能源系统中的应用

• 批准号: 0322101
• 负责人: Ali Nayfeh
• 金额: --
• 依托单位: Virginia Polytechnic Institute and State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-08-01 至 2008-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0322101&HistoricalAwards=false
• 关键词: US; Egypt; Cooperative; Research; Application

0322101 NayfehDescription: This award supports a cooperative research project between Professor AliNayfeh, Department of Engineering Sciences and Mechanics, Virginia Polytechnic Institute and State University (Virginia Tech.), Blacksburg, Virginia and Dr. Ayman El-Badawy, Department of Mechanical Engineering, Al-Azhar University, Cairo, Egypt. They plan to study the suppression of the large-amplitude vibrations of self-excited systems and systems with limited power supplies. The control strategy will be based on the saturation phenomenon exhibited by multi-degree-of-freedom systems with quadratic nonlinearities possessing a two-to-one autoparametric resonance. The strategy consists of introducing a second-order controller, and coupling it to the plant through a sensor and an actuator, where both the feedback and control signals are quadratic. Therefore, the desired nonlinearities can be introduced into the complete plant/control system even when the plant does not exhibit any nonlinear behavior. When the plant is forced near resonance, its response saturates at a small value, and the remaining oscillatory energy is channeled and absorbed by the actuator. The investigators will implement the technique by using a digital signal processing board and a modeling software. They will develop an adaptive control strategy using an effective frequency-tuning mechanism to maintain the two-to-one internal-resonance condition. Adaptive control makes it possible for the system (or structure) to adapt to a variable environment in the interest of continuously optimizing its performance. The investigators will examine the use of a logic gate with Schmitt-trigger action on the input to measure the system frequency because of its accuracy and because it is immune to noise disturbances.Scope: The project involves analytical and experimental approaches, and combines the complementary expertise of the US and Egyptian scientists. The self-excited oscillations are encountered in a number of important engineering systems, and the suppression of these oscillations, especially under the constraint of limited power supplies, is an important problem. The development of the active nonlinear feedback control will have many applications. The project will support an Egyptian scientist to work at Virginia Tech and will include interaction of students at both universities.

0322101 Nayfeh 描述：该奖项支持弗吉尼亚理工学院和州立大学（弗吉尼亚理工大学）（弗吉尼亚州布莱克斯堡）工程科学与力学系 AliNayfeh 教授与美国阿尔及尔机械工程系 Ayman El-Badawy 博士之间的合作研究项目-埃及开罗爱资哈尔大学。他们计划研究自激系统和电源有限的系统大幅振动的抑制。控制策略将基于具有二对一自参数共振的二次非线性多自由度系统所表现出的饱和现象。该策略包括引入二阶控制器，并通过传感器和执行器将其耦合到设备，其中反馈和控制信号都是二次的。 因此，即使设备没有表现出任何非线性行为，也可以将所需的非线性引入到整个设备/控制系统中。当设备被迫接近共振时，其响应在一个小值处饱和，剩余的振荡能量被执行器引导和吸收。 研究人员将通过使用数字信号处理板和建模软件来实施该技术。他们将开发一种自适应控制策略，使用有效的频率调谐机制来维持二对一的内部谐振条件。自适应控制使系统（或结构）能够适应变化的环境，从而不断优化其性能。 研究人员将检查在输入上使用具有施密特触发作用的逻辑门来测量系统频率，因为它的准确性和不受噪声干扰的影响。范围：该项目涉及分析和实验方法，并结合了互补的方法美国和埃及科学家的专业知识。 许多重要的工程系统都会遇到自激振荡，抑制这些振荡，特别是在有限电源的约束下，是一个重要的问题。 主动非线性反馈控制的发展将有许多应用。 该项目将支持一名埃及科学家在弗吉尼亚理工大学工作，并将包括两所大学学生的互动。