Download or read book Adaptive Sliding Mode Control with Application to a MEMS Vibratory Gyroscope written by Juntao Fei and published by . This book was released on 2007 with total page 168 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Gyroscopes are commonly used sensors for measuring angular velocity in many areas of applications such as navigation, homing, and control stabilization. Vibratory gyroscopes are the devices that transfer energy from one axis to the other through Coriolis forces. Fabrication imperfections result in some cross stiffness and cross damping effects that may hinder the measurement of angular velocity of MEMS gyroscope. Other noise sources such as thermal, mechanical noise also affect the performance. The angular velocity measurement and minimization of the cross coupling between two axes are challenging problems in the control of vibrating gyroscopes. This dissertation develops adaptive sliding mode control strategies for a MEMS z-axis gyroscope. The proposed adaptive sliding mode controllers for MEMS z-axis gyroscope make real-time estimates of the angular velocity as well as all unknown gyroscope parameters including coupling stiffness and damping parameters. Therefore, fabrication imperfection and time varying noise and disturbance can be compensated for. These estimates are updated using the tracking error between the reference model trajectory and mass' real trajectory. The reference model trajectory is designed to satisfy the persistence of excitation condition to enable parameter estimates to converge to their true values. The indirect adaptive sliding mode controller and direct adaptive sliding mode controller with proportional and integral sliding surface are proposed for MEMS gyroscope. In the presence of unmeasured velocity states, an adaptive sliding mode controller with a sliding mode observer that can reconstruct the unmeasured states is developed to estimate the angular velocity and the linear damping and stiffness coefficients of the gyroscope in real time despite parameter variations and external disturbance. Moreover, the adaptive sliding mode control for two axes angular sensor is extended to triaxial angular sensor and a novel concept for an adaptively controlled triaxial angular velocity sensor device that is able to detect rotation in the three orthogonal axes, using a single vibrating mass is proposed. The numerical simulations of MEMS gyroscope show the effectiveness of all the proposed adaptive sliding mode control schemes. It is shown that the proposed adaptive sliding mode control schemes offer several advantages such as consistent estimates of gyroscope parameters including angular velocity and large robustness to parameter variations and disturbance."--Abstract.

Download or read book Adaptive sliding mode control of a Mems vibratory gyroscope written by Juntao Fei and published by . This book was released on 2008 with total page 125 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book MEMS Vibratory Gyroscopes written by Cenk Acar and published by Springer Science & Business Media. This book was released on 2008-12-16 with total page 262 pages. Available in PDF, EPUB and Kindle. Book excerpt: MEMS Vibratory Gyroscopes provides a solid foundation in the theory and fundamental operational principles of micromachined vibratory rate gyroscopes, and introduces structural designs that provide inherent robustness against structural and environmental variations. In the first part, the dynamics of the vibratory gyroscope sensing element is developed, common micro-fabrication processes and methods commonly used in inertial sensor production are summarized, design of mechanical structures for both linear and torsional gyroscopes are presented, and electrical actuation and detection methods are discussed along with details on experimental characterization of MEMS gyroscopes. In the second part, design concepts that improve robustness of the micromachined sensing element are introduced, supported by constructive computational examples and experimental results illustrating the material.

Download or read book Whole Angle MEMS Gyroscopes written by Doruk Senkal and published by John Wiley & Sons. This book was released on 2020-05-11 with total page 176 pages. Available in PDF, EPUB and Kindle. Book excerpt: Presents the mathematical framework, technical language, and control systems know-how needed to design, develop, and instrument micro-scale whole-angle gyroscopes This comprehensive reference covers the technical fundamentals, mathematical framework, and common control strategies for degenerate mode gyroscopes, which are used in high-precision navigation applications. It explores various energy loss mechanisms and the effect of structural imperfections, along with requirements for continuous rate integrating gyroscope operation. It also provides information on the fabrication of MEMS whole-angle gyroscopes and the best methods of sustaining oscillations. Whole-Angle Gyroscopes: Challenges and Opportunities begins with a brief overview of the two main types of Coriolis Vibratory Gyroscopes (CVGs): non-degenerate mode gyroscopes and degenerate mode gyroscopes. It then introduces readers to the Foucault Pendulum analogy and a review of MEMS whole angle mode gyroscope development. Chapters cover: dynamics of whole-angle coriolis vibratory gyroscopes; fabrication of whole-angle coriolis vibratory gyroscopes; energy loss mechanisms of coriolis vibratory gyroscopes; and control strategies for whole-angle coriolis vibratory gyro- scopes. The book finishes with a chapter on conventionally machined micro-machined gyroscopes, followed by one on micro-wineglass gyroscopes. In addition, the book: Lowers barrier to entry for aspiring scientists and engineers by providing a solid understanding of the fundamentals and control strategies of degenerate mode gyroscopes Organizes mode-matched mechanical gyroscopes based on three classifications: wine-glass, ring/disk, and mass spring mechanical elements Includes case studies on conventionally micro-machined and 3-D micro-machined gyroscopes Whole-Angle Gyroscopes is an ideal book for researchers, scientists, engineers, and college/graduate students involved in the technology. It will also be of great benefit to engineers in control systems, MEMS production, electronics, and semi-conductors who work with inertial sensors.

Download or read book Adaptive Control Strategies for MEMS Gyroscopes written by Sungsu Park and published by . This book was released on 2000 with total page 382 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Sliding Mode Control and the Least Squares Estimation of Angular Rate for a MEMS Vibratory Gyroscope written by Sreeram Reddy Tadvai and published by . This book was released on 2004 with total page 172 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Advanced Control Design of MEMS Vibratory Gyroscopes written by Juntao Fei and published by . This book was released on 2011-10 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: MEMS (Micro Electro Mechanical Systems) technologies were developed by applying semiconductor microfabrication technologies to make three-dimensional microstructures and mechanical systems. MEMS technologies offer the advantages of batch fabrication of numbers of devices as well as an ability to integrate multiple functional units in a small area, which is important for developing smart and sophisticated devices. Gyroscopes are commonly used sensors for measuring angular velocity in many areas of applications such as navigation, homing, and control stabilisation. Fabrication imperfections and thermal, mechanical noise may hinder the measurement of angular velocity of MEMS gyroscope. This book presents a comprehensive treatment of the analysis and advanced control design of MEMS gyroscope for the problem of angular velocity measurement and minimisation of the cross coupling between two axes.

Download or read book Sliding Mode Control Using MATLAB written by Jinkun Liu and published by Academic Press. This book was released on 2017-05-25 with total page 348 pages. Available in PDF, EPUB and Kindle. Book excerpt: Sliding Mode Control Using MATLAB provides many sliding mode controller design examples, along with simulation examples and MATLAB® programs. Following the review of sliding mode control, the book includes sliding mode control for continuous systems, robust adaptive sliding mode control, sliding mode control for underactuated systems, backstepping, and dynamic surface sliding mode control, sliding mode control based on filter and observer, sliding mode control for discrete systems, fuzzy sliding mode control, neural network sliding mode control, and sliding mode control for robot manipulators. The contents of each chapter are independent, providing readers with information they can use for their own needs. It is suitable for the readers who work on mechanical and electronic engineering, electrical automation engineering, etc., and can also be used as a teaching reference for universities. Provides many sliding mode controller design examples to help readers solve their research and design problems Includes various, implementable, robust sliding mode control design solutions from engineering applications Provides the simulation examples and MATLAB programs for each sliding mode control algorithm

Download or read book Adaptive Control System for a Vibrational MEMS Gyroscope with Time varying Rotation Rates written by Lili Dong and published by . This book was released on 2005 with total page 236 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Adaptive Control for Conventional Modes of Operation of MEMS Gyroscopes written by Sungsu Park and published by . This book was released on 2002 with total page 34 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Adaptive Force Balancing Control of MEMS Gyroscope System with Magnitude Constraints written by Hameed Abdul Mohammed and published by . This book was released on 2003 with total page 140 pages. Available in PDF, EPUB and Kindle. Book excerpt: "This thesis work presents a suite of adaptive force-balancing control schemes with magnitude constraints on the input for a MEMS (Microelectromechanical systems) z-axis gyroscope."--Abstract, p. iii.

Download or read book Adaptive Control for MEMS Gyroscopes written by Sungsu Park and published by . This book was released on 2002 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Contribution to Adaptive Sliding mode Control with Gaussian Radial basis function Networks written by Lei Ma and published by . This book was released on 2006 with total page 129 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Digital Implementation of Adaptive Control Algorithms for MEMS Gyroscopes written by Sungsu Park and published by . This book was released on 2002 with total page 35 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Adaptive Control for a Simulated Micro Electro Mechanical Vibrating Gyroscope written by Qais A. Khasawneh and published by . This book was released on 2002 with total page 156 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Mechanical Design Dynamics and Control of Micro Vibratory Gyroscopes written by Seyed Parsa Taheri Tehrani and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Micro-machined vibratory gyroscopes are very small devices (up to a few millimeters in dimension) that work based on Coriolis force coupling between two resonance modes. The small size, low power consumption, and cheap price make these sensors popular in automotive, gaming, smart phones, and robotics industries. These sensors referred to as MEMS (microelectromechanical system) gyroscopes are currently not used for navigation applications because due to their miniature size and imperfections in fabrication methods they do not have enough accuracy. In this thesis, we present methods in design and control algorithms for MEMS vibratory gyroscopes to cancel the effect of imperfections in fabrication and improve gyroscopes' performance. First chapter of this thesis is an introduction on MEMS vibratory gyroscopes and their principles and standard operations modes.The second chapter presents the structural design and analysis of a single-structure 3-axis MEMS gyroscope. The gyroscope has four resonant modes of interest and uses a decoupling mechanism whereby auxiliary masses are used to actuate the drive mode of the gyroscope in order to reduce drive-force coupling to sense modes' motion (one of the sources of errors in MEMS gyroscopes). The use of auxiliary masses results in a two degree-of-freedom (DOF) mechanism of the drive mode. To compare the effectiveness of using auxiliary masses two gyroscope types has been design one actuated from auxiliary masses (type A) and one actuated from major masses (type B). The two designs are simulated analytically to study the displacement of each mass in each design while comparing the force required to achieve that displacement for drive mode. Experimental data from fabricated devices show how using auxiliary masses will decrease drive force coupling and as a result improve the gyroscope's performance. Third chapter describes the operation of a high quality factor gyroscope in various regimes where electromechanical nonlinearities introduce different forms of amplitude-frequency (A-f) dependence. Experiments are conducted using an epitaxially-encapsulated 2 x 2 mm2 quad-mass gyroscope (QMG) with a quality factor of 85,000. The device exhibits third-order Duffing nonlinearity at low bias voltages (15 V) due to the mechanical nonlinearity in the flexures and at high bias voltages (35 V) due to third-order electrostatic nonlinearity. At intermediate voltages (26 V), these third-order nonlinearities cancel and the amplitude-frequency dependence is greatly reduced. A model is developed to demonstrate the connection between the electromechanical nonlinearities and the amplitude-frequency dependence, also known as the backbone curve. Gyroscope operation is demonstrated in each nonlinear operating regime and the key performance measures of the gyroscope's performance, angle random walk (ARW) and bias instability, are measured as a function of drive-mode vibration amplitude. While the bias instability is nearly independent of the drive-mode’s nonlinearity, we find that ARW increases when the third-order nonlinearities are minimized, and the decrease in ARW due to increase of amplitude is independent of drive mode's type of nonlinearity.In the fourth chapter we present a direct angle measurement method in gyroscopes. Towards the objective of direct angle measurement using a rate integrating gyroscope (RIG) without a minimum rate threshold and performance limited only by electrical and mechanical thermal noise, in this chapter we present the implementation of a generalized electronic feedback method for the compensation of MEMS gyroscope damping asymmetry (anisodamping) and stiffness asymmetry (anisoelasticity) on a stand-alone digital signal processing (DSP) platform. Using the new method, the precession angle dependent bias error and minimum rate threshold, two issues identified by Lynch for a MEMS RIG due to anisodamping are overcome. To minimize angle dependent bias, we augment the electronic feedback force of the amplitude regulator with a non-unity gain output distribution matrix selected to correct for anisodamping. Using this method, we have decreased the angle dependent bias error by a factor of 30, resulting a minimum rate threshold of 2.5 dps. To further improve RIG performance, an electronically-induced self-precession rate is incorporated and successfully demonstrated to lower the rate threshold.

Download or read book MEMS Vibratory Gyroscopes written by Cenk Acar and published by . This book was released on 2008 with total page 256 pages. Available in PDF, EPUB and Kindle. Book excerpt: