Chen Xianfeng, de Lint Tjebbe, Alijani Farbod, Steeneken Peter G
Department of Precision and Microsystems Engineering, Delft University of Technology, Mekelweg 2, 2628 CD Delft, The Netherlands.
A*STAR Quantum Innovation Centre (Q.InC), Institute for Materials Research and Engineering (IMRE), Agency for Science, Technology and Research (A*STAR), 2 Fusionopolis Way, 08-03, Innovis, 138634 Singapore, Singapore.
Nonlinear Dyn. 2024;112(21):18807-18816. doi: 10.1007/s11071-024-10018-x. Epub 2024 Jul 20.
The ultimate isolation offered by levitation provides new opportunities for studying fundamental science and realizing ultra-sensitive floating sensors. Among different levitation schemes, diamagnetic levitation is attractive because it allows stable levitation at room temperature without a continuous power supply. While the dynamics of diamagnetically levitating objects in the linear regime are well studied, their nonlinear dynamics have received little attention. Here, we experimentally and theoretically study the nonlinear dynamic response of graphite resonators that levitate in permanent magnetic traps. By large amplitude actuation, we drive the resonators into nonlinear regime and measure their motion using laser Doppler interferometry. Unlike other magnetic levitation systems, here we observe a resonance frequency reduction with amplitude in a diamagnetic levitation system that we attribute to the softening effect of the magnetic force. We then analyze the asymmetric magnetic potential and construct a model that captures the experimental nonlinear dynamic behavior over a wide range of excitation forces. We also investigate the linearity of the damping forces on the levitating resonator, and show that although eddy current damping remains linear over a large range, gas damping opens a route for tuning nonlinear damping forces via the squeeze-film effect.
The online version contains supplementary material available at 10.1007/s11071-024-10018-x.
悬浮所提供的终极隔离为研究基础科学和实现超灵敏浮动传感器提供了新机会。在不同的悬浮方案中，抗磁悬浮很有吸引力，因为它能在室温下实现稳定悬浮且无需持续供电。虽然抗磁悬浮物体在线性区域的动力学已得到充分研究，但其非线性动力学却很少受到关注。在此，我们通过实验和理论研究了在永磁阱中悬浮的石墨谐振器的非线性动态响应。通过大幅度驱动，我们将谐振器驱动到非线性区域，并使用激光多普勒干涉测量法测量其运动。与其他磁悬浮系统不同，在此抗磁悬浮系统中，我们观察到共振频率随振幅降低，我们将其归因于磁力的软化效应。然后，我们分析了不对称磁势，并构建了一个模型，该模型能在广泛的激发力范围内捕捉实验非线性动态行为。我们还研究了悬浮谐振器上阻尼力的线性度，并表明尽管涡电流阻尼在很大范围内保持线性，但气体阻尼通过挤压薄膜效应为调整非线性阻尼力开辟了一条途径。
在线版本包含可在10.1007/s11071-024-10018-x获取的补充材料。
