The Atomic Force Microscope as a Machine Tool: Modelling, Robust Control Design, and Hardware

9632820 Dahleh精密加工是一项重要的新兴技术，在光学、微电子、磁和光记录以及传感器和执行器等多个领域具有制造应用。随着小型化的趋势，预计开发工具来塑造微米和纳米尺度的材料的需求将继续增加。鉴于此，我们建议设计、制造和使用一种基于原子力显微镜(AFM)概念的机床。原子力显微镜是最近的一项发明，到目前为止，它已经被用于以原子尺度、横向和垂直分辨率对表面进行成像。它在样品表面扫描锋利的触针探头，同时通过反馈控制系统保持探头尖端和样品表面之间的恒定接触力。我们建议使用测针作为刀具，该系统具有以下特点：(1)切深范围为1 nm-10um，表面光洁度为0.1 nm-1 nm；(2)刀具上的法向力和切向力将以10nN到1un的分辨率同时测量；(3)刀具-工件相对运动可以是旋转和/或平移的；(4)闭环系统的鲁棒控制将保持恒定的刀具-样品力或刀具-样品距离；(5)可以在1 nm范围内以空间和垂直分辨率成像工件表面；(6)可将工件表面图案化为任何所需形状--旋转对称或非对称；(7)可在30 nm-10微米范围内进行横向分辨率的加工。这些特点将使拟议的设计优于现有的精密加工工具。该项目的目标有两个--(1)开发一种自动化和多功能的精密加工和成像工具；(2)建立一个原型设备，用于研究和验证纳米级的控制方法、识别方法、控制接口和机械加工。***

9632820 Dahleh Precision machining is an important emerging technology with manufacturing applications in diverse fields such as optics, microelectronics, magnetic and optical recording as well as sensors and actuators. With trends in miniaturization, the need to develop tools to shape materials as micrometer and nanometer scales is expected to keep increasing. In view of this, we propose to design, fabricate and use a machine tool which is based on the concept of the atomic force microscope (AFM). The AFM is a recent invention which has so far been used to image surfaces with atomic scale lateral and vertical resolution. It scans a sharp stylus probe across a sample surface while maintaining a constant contact force between the probe tip and the sample surface through a feedback control system. We propose to use the stylus probe as a cutting tool with the system having the following features--(1) depths-of-cut will range from 1nm - 10um with surface finishes ranging from 0.1 nm -1 nm; (2) normal and tangential forces on the tool will be simultaneously measured with 10 nN to 1 uN resolution; (3) tool-workpiece relative motion can be rotational and/or translational; (4) closed loop robust control will maintain constant either the tool-sample force or the tool-sample distance; (5) workpiece surface can be imaged with spatial and vertical resolution in 1nm range; (6) workpiece surface can be patterned to any desired shape - rotationally symmetric or non-symmetric; (7) machining can be done with lateral resolution in the 30 nm - 10 um range. These features will make the proposed design superior to existing precision machining tools. The objectives of this project are two-fold -- (1) to develop an automated and versatile precision machining and imaging tool; (2) to build a prototype device for the study and validation of control methodologies, identification methods, and the interface of control and the mechanics of machining at a nano-scale. ***