CAREER: Modeling, Dynamical Analysis, and Control of Microcantilever Based Devices

在过去的十年里，Salapaka微悬臂使显微镜发生了革命性的变化。巧妙地使用它们的方法已经被用来在非常小的范围内探测和操纵材料。这种结构使研究成为可能，这就是为什么在《科学》和《自然》等知名期刊上发表了大量文章。它们在生物学(DNA链已被用微悬臂梁操纵)和半导体加工等不同领域得到了广泛的应用。最近利用微悬臂梁的一些研究是在纳米加工和电子自旋检测领域，尽管控制设计对这类系统很重要，但对控制器的作用的系统研究一直被忽视。拟议的项目将进行这样一项研究，其主要目标是获得基于微悬臂梁的设备的面向控制的模型，并利用这些模型来设计和实施控制器。在这些模型的基础上，将制定一种评估这种装置的性能极限的方法。初步研究表明，这样的研究可以取得巨大的进步。为了有效地设计这样的系统的控制器，需要对基本的物理原理有很好的理解。有一些新奇的现象会对性能产生不利影响，但有助于签名过程。例如，使用微悬臂梁的系统中的热噪声可能是可实现性能的限制因素。然而，利用热噪声，可以直接获得标称模型和建模误差的界。这些现象将被研究和利用来建模。正在进行的研究表明，在悬臂-样品动力学中，复杂的行为是可能的。控制设计对于稳定存在于复杂动力学中的期望行为具有重要作用。提高运行速度和更好的分辨率是这种设计的重要好处，这将在本项目下进行。此外，随着微型化程度的提高，微悬臂梁中的量子力学效应开始变得相关，控制这种效应的需要变得重要。悬臂梁设备的任何模型中的不确定性都是不可避免的。这种不确定性的原因之一是，悬臂的动力学是由悬臂所探测的材料决定的。此外，在这种设备中存在的一些干扰被描述为随机框架，而其他干扰被描述为确定性的、时间域设置。因此，能够在存在不确定性的情况下处理与此类扰动有关的性能规范的控制器可能特别有价值。提出了在使用微悬臂梁的设备中更好地研究此类控制器的技术、软件开发和实现。将开发一门课程，培训学生关于设计的建模、验证和实现问题。这门课程将包括理论和实验的适当结合。与基于微悬臂的设备相关的方面也将包括在内。企业家的演讲将突出一个项目成功需要考虑的财务问题。在另一门课程中，将介绍基于凸性理论的控制器设计的最新方法。本课程将统一在控制器设计中使用的大多数凸性分析技术。将给出设计此类控制器的有效计算工具。***

9733802SalapakaMicro-cantilevers have revolutionized microscopy in the past decade. Ingenious ways of using them have been deviced to probe and manipulate material at very small scale. Research made possible by such structures is the reason for numerous articles in reputed journals such as Science and Nature. They have found widespread use in diverse areas such as biology (DNA strands have been manipulated using micro-cantilevers) and semiconductor processing. Some of the recent research which utilize micro-cantilevers are in the areas of nano-machining and electron spin detection.Inspite of the importance of control design for such systems, a systematic study of the role of controllers has been neglected. The proposed project will perform such a study where the primary objective is to obtain control-oriented models for micro-cantilever based devices, and the utilization of such models to design and implement controllers. Based on such models a methodology to assess the limits of performance of such a device will be developed. Initial research has indicated that vast advances can be made by such a study.For effective design of controllers for such systems a good understanding of the underlying physical principles is required. There are novel phenomena which affect the performance adversely but can aid the sign process. As an example, thermal noise in systems utilizing micro-cantilevers can be the limiting factor in the achievable performance. However, using thermal noise, nominal model and bounds on modeling errrors can be obtained in a straightforward manner. Such phenomena will be studied and exploited for modeling.Ongoing research has indicated that complex behavior is possible in the cantilever-sample dynamics. Control design can play an important role in stabilizing desirable behavior that exist amidst the complex dynamics. Increased speeds of operation and better resolutions are the important benefits of such a design, which will be pursued under this project. Also, with increasing miniaturization the quantum-mechanical effects in the micro-cantilever start to become relevant and a need to control such effects becomes important.Uncertainty in any model for a cantilever based device is unavoidable. One of the reasons for such uncertainty is that the cantilever dynamics is determined by the material being probed by the cantilever. Moreover, some disturbances present in such devices are characterized in a stochastic framework while others are described in a deterministic, time-domain setting. Thus controllers which can handle performance specifications with respect to such disturbances in the presence of uncertainty can be particularly valuable. The study of better techniques, software development and implementation of such controllers in a device which employs a micro-cantilever is proposed.A course which educates the student in modeling, validation and implementation issues of design will be developed. This course will comprise of an appropriate combination of theory and experiment. Aspects relevant to micro-cantilever based devices will also be incorporated. Lectures to be given by entrepreneurs will highlight the financial issues to be considered for the success of a project. In another course, recent methodologies ofcontroller design which rely on convexity theory will be presented. This course will unify most of the convex analysis techniques that are being utilized in the design of contollers. Efficient computational tools to design such controllers will be given. ***