Manuel Collet是法国科学院(CNRS)的高级研究员,法国中央理工大学摩擦与系统动力学实验室(LTDS)主任,Carnot Ingénierie@Lyon研究院主席。他主要关注智能结构的基础理论研究及其在能量收集、振动噪声控制等方面的应用,是美国机械工程师协会(ASME)著名国际会议SMASIS系列的主要组织者之一。
2019年12月27日,应宇航学院胡更开教授邀请,美国科罗拉多博尔德大学(University of Colorado Boulder)航天工程与科学系Mahmoud I. Hussein教授来宇航学院进行学术访问与交流,并做了题为《Dissipation engineering in metamaterials by localized structural dynamics》的学术报告。
Mahmoud I. Hussein 是科罗拉多博尔德大学航天工程与科学系教授,并分别在应用数学系与工程和应用科学学院担任兼职教授和Pre-Engineering项目主任。Hussein教授的主要研究领域为材料和结构的动力学特性,尤其在声子晶体和局域谐振超材料方面成就显著。Hussein教授在2011年获得了DARPA Young Faculty奖,并在2013年获得了NSF CAREER奖,同时在2017年获得了科罗拉多博尔德大学Provost’s Faculty Achievement奖。Hussein教授与他人合编出版了《Dynamics of Lattice Materials》,同时也是ASME Fellow 以及 《Journal of Vibration and Acoustics》的副主编。此外,Hussein教授还是国际声子协会(International Phononics Society)的创始副会长,并共同创立了“Phononics 20xx”系列会议,该系列会议是国际公认的声子晶体领域顶级会议。
The term tensegrity, derived trom tensional integrity, refers to a ccrtain class of structural systems composed of bars and strings. Through adequate pre-stressing of their string members, tensegrity structures generally become mechanically stable. Traditional approaches for modeling their behavior assume that (i)bars are perfectly rigid. (ii)cables are linear elastic, and (iii) bars experience pure compression and strings pure tension. In addition, a common design constraint is to assume that the structure would fail whenever any ot its bars reaches the corresponding Euler buckling load. In reality, these assumptions tend to break down in the presence of dynamic events. In the first part of this talk. we will introduce a physics-based reduced-order model to study aspects related to the dynamic and nonlinear response of tensegrity bascd planetary landers. We will then adopt our model to show how, under dynamic events, buckling of individual members of a tensegrity structure does not necessarily imply structural failure. thus signilicantly expanding the design space for such vehicles. In the second part of this talk, we will show how lessons learned from our tensegrity planetary lander can be translated into to the development novel metamaterials. We will introduce the first known class-two 3D tensegrity metamaterial. and show that this new topology exhibits unprecedented static and dynamic mechanical properties.