Semi-automated optimal vibration suppression of flexible structures

拟议研究计划的总体目标是开发一种创新的方法来优化柔性结构的振动抑制。由于结构的变化，通常使用的被动减振器会随着时间的推移而失谐。为了补偿这些偏差，需要采用主动振动控制方案。然而，这些技术除了需要大量的控制努力外，还受到控制引起的不稳定性的影响。利用半主动和主动分段并行使用的特点，提出了一种智能半自动替代方案。半主动部分包括从ER/MR阻尼器到磁致伸缩致动器的智能结构，而一组特定的压电致动器构成了主动部分。通过改变可调结构属性(在半主动单元中)和控制参数(在主动单元中)，进行搜索以最小化受约束的目标函数，该目标函数可以反映性能特性。在实践中，工程师在回路中解释所产生的性能，并可能启动多个选项：控制优化、半主动部件优化或两者的组合。拟议研究的主要活动将是通过数字工具发展和促进这一解释性决策。通过智能材料的适当调整，应使用半主动单元(耗电最小的努力)将振动抑制到可能的程度，而主动吸振器单元则处理剩余的振动抑制要求。如果所产生的设计不可接受或如果系统参数显示变化，则触发解释程序以改变半主动单元的参数，或重新调整主动单元的控制参数，或同时调整两者。这些特点是非常重要的，并将扩大减振器在工业应用中的用途，在工业应用中遇到广泛的结构变化。通过对单自由度系统的仿真，验证了该方法的可行性。当在具有复杂动力学和可控性的现实系统上实施时，挑战在于开发用于混合治疗的智能决策过程。

The overall objective of the proposed research program is to develop an innovative approach for optimum vibration suppression of flexible structures. Commonly used passive vibration absorbers become de-tuned over time due to the structural variations. In order to compensate for these deviations, active vibration control schemes are needed. These techniques, however, suffer from the control induced instability in addition to the large control effort requirement. Utilizing concurrent use of semi-active and active subsections, an intelligent semi-automated alternative is suggested. The semi-active subsection includes smart structures ranging from ER/MR dampers to magnetostrictive actuators, and a particular set of piezoelectric actuators forms the active subsection. By altering the adjustable structural properties (in semi-active unit) and control parameters (in active unit), a search is conducted to minimize an objective function subject to constraints, which may reflect performance characteristics. In practice, an engineer in-the-loop interprets the resulting performance and may initiate a number of options: control optimization, semi-active component optimization, or combination of the two. The predominant activity of the proposed study will be to develop and facilitate this interpretive decision making via numerical tools. The vibration should be suppressed to the possible extent using a semi-active unit (the least power consuming effort) through proper adjustment of smart materials, while the active absorber unit handles the remaining vibration suppression requirement. If the resulting design is not acceptable or if system parameters show variations, an interpretation procedure triggers to alter the parameters of the semi-active unit, or retune the control parameters of active unit, or concurrently adjust both. These features are very important and will broaden the utility of the vibration absorbers in industrial applications where a wide range of structural variations is encountered. The feasibility of the proposed method is demonstrated through the simulations of a SDOF system. The challenge lies in the development of intelligent decision-making processes for hybrid treatment when implemented on realistic systems with complex dynamics and controllability.