Optimal control of ultrasoft cantilevers for force microscopy
Optimal control of ultrasoft cantilevers for force microscopy
复制标题
用于力显微镜的超软悬臂的优化控制
DOI：
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发表时间：
1998
期刊：
影响因子：
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通讯作者：
J. Sidles
中科院分区：
文献类型：
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作者：
K. J. Bruland;J. Garbini;W. Dougherty;J. Sidles
力显微镜最优控制的目标是：(1)获得良好的悬臂梁动态特性；(2)将悬臂梁控制到所需的幅度；(3)施加尽可能小的控制力；(4)保持未受控悬臂梁的力信噪比。本文描述了实现这些目标的最优控制器的实验实现。将该控制器应用于弹性常数为110μN/m、温度为10 K的超柔性悬臂梁，使其谐振质量从15 000降至2 2 0，布朗幅值从11 2 A降至1 4 A，所需控制力小于7×10−17 N，力灵敏度保持在9 8×10−18 N/ Hz不变，并证明了反馈控制能迫使悬臂梁运动跟踪参考输入。
The goals of optimal control in force microscopy are: (1) to obtain favorable cantilever dynamic properties and (2) to control the cantilever to a desired amplitude, while (3) exerting as little control force as possible, and (4) preserving the force signal-to-noise ratio of the uncontrolled cantilever. This article describes the experimental implementation of an optimal controller that achieves these goals. The application of this controller to an ultrasoft cantilever with spring constant of 110 μN/m at 10 K reduced the resonant quality from 15 000 to 220, reduced the Brownian amplitude from 11.2 A to 1.4 A, used less than 7×10−17 N of control effort, left the force sensitivity unaltered at 9.8×10−18 N/ Hz, and demonstrated feedback control can force cantilever motion to track a reference input.