Vibration reduction by energy transfer using shape adaption

轻量化设计是工程设计中的重要问题之一。其目的是减少结构部件的质量，以节省制造和运营过程中的成本，能源和资源。然而，结构越轻，就越容易产生不必要的振动。减振措施可以通过被动、半主动或主动措施来实现，其中被动措施是指不需要外部能量，而半主动和主动措施分别利用外部能量来控制耗散或直接抵消振动运动。由于主动措施通常不依赖于耗散，因此它们不属于招标范围，也不在本项目中考虑。在被动和半主动措施领域中，可以使用两种一般方法来减少结构中的振动，即阻尼方法，其是将动能耗散成另一种形式的能量，或者吸收方法，这种设想的方法将以一种新的方式将阻尼和吸收的概念联合收割机结合起来，因此，本发明的目的在于将阻尼的调谐质量吸收器的功能性转化为形状自适应结构。通过使用横截面的形状适应来动态适应细长梁状结构的刚度，动能将从临界低频弯曲模式转移到专门设计的较高频率吸收器模式中，然后可以以最佳方式进行阻尼。形状自适应机构和吸收器模式的优化设计将采用柔顺机构。耗散将通过专门设计的摩擦阻尼器进行优化。

Lightweight design is one of the most important issues in engineering design. The objective is to reduce the mass of structural components for the purpose of saving costs, energy and resources in manufacturing and operation processes. However, the lighter the structure is, the more it is prone to unwanted vibrations. Such vibrations should be minimized in order to prevent the environment, products and human beings from being harmed and to maximize the lifetime of the products.Vibration reduction can be achieved by passive, semi-active or active measures, where passive means that no external energy is needed, while semi-active and active measures employ external energy to either control dissipation or directly counteract the vibrational motion, respectively. Since active measures usually do not rely on dissipation, they do not fall in the scope of the call for proposals and will not regarded in this project. In the realm of passive and semi-active measures, two general approaches can be used to reduce vibration in structures, namely that of damping, which is the dissipation of kinetic energy into another form of energy, or that of absorption, which is the transfer of kinetic energy from a critical mode into an uncritical mode.The envisioned approach will combine the concepts of damping and absorption in a novel way by integrating the functionality of a damped, tuned mass absorber into a shape adaptive structure. By dynamically adapting the stiffness of a slender, beam-like structure using shape adaption of the cross-section, kinetic energy will be transferred from the critical low-frequency bending modes into a specifically designed, higher frequency absorber mode, which can then be damped in an optimal way. Optimal design of the shape adaption mechanism and of the absorber mode will be pursued using compliant mechanisms. The dissipation will be optimized by a specifically designed friction damper.