Dynamic Friction Models for Micro and Nanosystems

摘要：该项目的目的是将独特的实验和悠久的摩擦建模传统相结合，开发可用于NEMS和MEMS系统摩擦补偿的动态摩擦模型。由于独特的实验设备的可获得性，加州大学伯克利分校微系统表征实验室的Hysitron纳米压痕中心提供了通过精确实验改善摩擦模型技术水平的有趣可能性。PI和Co-PI将建模和实验微尺度力学的专业知识结合在一起，试图对观察到的实验现象进行建模。微压头的一个有趣特性是，通过改变尖端的设计，可以在不同的尺度上进行类似的实验。这可能使在类似的实验中比较原子摩擦和宏观摩擦成为可能。这一建议的智力优点在于不仅能够建立基于物理的摩擦模型，而且能够进行精确的实验来验证这些模型，并产生改进的模型。在这项可行性研究(探索性基础研究)中，研究小组打算探索纳米压头可以做些什么，并对改进的摩擦模型进行初步调查。一个特别的重点将是在慢速度下的小位移的摩擦力的性质。其假设是，这样的实验将带来相当大的洞察力。如果这是真的，那么包括纳米和宏观尺度在内的更详细的研究计划就有很大的余地。PI和Co-PI在本科生教育中都非常活跃。如果这个项目成功，本科生研究人员将通过REU补充参与进来。此外，开发的模型将被纳入加州大学伯克利分校机械工程本科课程的MEMS课程。由于这是为期一年的SGER，初步工作将主要以研究为基础，许多更广泛的影响成果将在资金期限之后产生。

Dynamic friction models for micro and nano-systemsAbstract: The purpose of this project is to combine unique experiments with a long tradition of friction modeling to develop dynamic models of friction that can be used for friction compensation in NEMS and MEMS systems. The availability of unique experimental equipment, the Hysitron nanoindenter in the Microsystems Characterization Lab at UCSB offers interesting possibilities to improve the state of the art of friction models through precise experiments. The PI and Co-PI bring together expertise in modeling and experimental microscale mechanics to attempt to model the observed experimental phenomena. An interesting property of the microindenter is that is may be possible to make similar experiments in different scales by changing the tip design. This may make it possible to compare friction atomic and macro-scale in similar experiments.The intellectual merit of this proposal lie in the ability to not only create physically based friction models, but in performing precise experiments which will verify such models, and yield improved ones. In this feasibility study (exploratory basic research) the team intends to explore what can be done with the nanoindenter and to make a preliminary investigation of improved friction models. A particular focus will be on the nature of friction forces for small displacements at slow velocities. The hypothesis is that such experiments will give considerable insight. If this is true there is significant scope for a more elaborate research program including both the nano and the macro scale. Both the PI and the Co-PI are very active in education of undergraduates. Should this project be successful, undergraduate researchers will be involved though REU supplements. In addition, the models developed will be incorporated into the MEMS curriculum in the undergraduate Mechanical Engineering courses at UCSB. As this is a one-year SGER, preliminary work will be primarily research-based, and many broader impact outcomes will occur after the duration of the funding.