Acar / Shkel MEMS Vibratory Gyroscopes

Structural Approaches to Improve Robustness
1. Auflage 2008
ISBN: 978-0-387-09536-3
Verlag: Springer
Format: PDF
Kopierschutz: 1 - PDF Watermark

E-Book, Englisch, 260 Seiten

Reihe: MEMS Reference Shelf

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.

Autoren/Hrsg.

Acar, Cenk

Shkel, Andrei

Inhaltsverzeichnis

1;Preface;7
2;Contents;9
3;Fundamentals of Micromachined Vibratory Gyroscopes;13
3.1;Introduction;14
3.1.1;1.1 The Coriolis Effect;14
3.1.2;1.2 Gyroscopes;15
3.1.3;1.3 The MEMS Technology;16
3.1.4;1.4 Micromachined Vibratory Rate Gyroscopes;17
3.1.5;1.5 Applications of MEMS Gyroscopes;19
3.1.6;1.6 Gyroscope Performance Specifications;19
3.1.7;1.7 A Survey of PriorWork on MEMS Gyroscopes;21
3.1.8;1.8 The Robustness Challenge;25
3.1.9;1.9 Inherently Robust Systems;26
3.1.10;1.10 Overview;27
3.2;Fundamentals of Micromachined Gyroscopes;28
3.2.1;2.1 Dynamics of Vibratory Rate Gyroscopes;28
3.2.2;2.2 Resonance Characteristics;36
3.2.3;2.3 Drive-Mode Operation;39
3.2.4;2.4 The Coriolis Response;40
3.2.5;2.5 Summary;53
3.3;Fabrication Technologies;54
3.3.1;3.1 Microfabrication Techniques;54
3.3.2;3.2 Bulk Micromachining Processes;63
3.3.3;3.3 Surface-Micromachining Processes;70
3.3.4;3.4 Combined Surface-Bulk Micromachining;74
3.3.5;3.5 CMOS Integration;75
3.3.6;3.6 Packaging;78
3.3.7;3.7 Summary;82
3.4;Mechanical Design of MEMS Gyroscopes;83
3.4.1;4.1 Mechanical Structure Designs;83
3.4.2;4.2 Linear Vibratory Systems;84
3.4.3;4.3 Torsional Vibratory Systems;97
3.4.4;4.4 Anisoelasticity and Quadrature Error;103
3.4.5;4.5 Damping;112
3.4.6;4.6 Material Properties of Silicon;117
3.4.7;4.7 Design for Robustness;118
3.4.8;4.8 Summary;120
3.5;Electrical Design of MEMS Gyroscopes;121
3.5.1;5.1 Introduction;121
3.5.2;5.2 Basics of Capacitive Electrodes;121
3.5.3;5.3 Electrostatic Actuation;123
3.5.4;5.4 Capacitive Detection;127
3.5.5;5.5 Capacitance Enhancement;130
3.5.6;5.6 MEMS Gyroscope Testing and Characterization;134
3.5.7;5.7 Summary;149
4;Structural Approaches to Improve Robustness;150
4.1;Linear Multi-DOF Architecture;151
4.1.1;6.1 Introduction;151
4.1.2;6.2 Fundamentals of 2-DOF Oscillators;152
4.1.3;6.3 The 2-DOF Sense-Mode Architecture;157
4.1.4;6.4 The 2-DOF Drive-Mode Architecture;166
4.1.5;6.5 The 4-DOF System Architecture;174
4.1.6;6.6 Demonstration of 2-DOF Oscillator Robustness;188
4.1.7;6.7 Summary;193
4.2;Torsional Multi-DOF Architecture;194
4.2.1;7.1 Introduction;194
4.2.2;7.2 Torsional 3-DOF Gyroscope Structure and Theory of Operation;196
4.2.3;7.3 Illustration of a MEMS Implementation;202
4.2.4;7.4 Experimental Characterization;208
4.2.5;7.5 Summary;213
4.3;Distributed-Mass Architecture;214
4.3.1;8.1 Introduction;214
4.3.2;8.2 The Approach;214
4.3.3;8.3 Theoretical Analysis of the Trade-offs;220
4.3.4;8.4 Illustrative Example ;222
4.3.5;8.5 Summary;231
4.4;Conclusions and Future Trends;232
4.4.1;9.1 Introduction;232
4.4.2;9.2 Comparative Analysis of the Presented Concepts;233
4.4.3;9.3 Demonstration of Improved Robustness;234
4.4.4;9.4 Scale Factor Trade-off Analysis;239
4.4.5;9.5 Future Trends;243
4.4.6;9.6 Conclusion;252
5;References;253
6;Index;261