Compliant Mechanisms: Design of Flexure Hinges 2nd Edition

Book Preface

Since the first edition publication of this book, substantial developments have occurred in the field of flexure-based compliant mechanisms, both at the modeling (analysis) and at the design (synthesis) levels, as reflected by the impressive num-ber of publications in scientific journals and monographs. While the major topics of the first edition, such as the analytical description of flexure hinges in terms of compliances, the static, dynamic and finite element modeling of hinge-based compliant mechanisms, have solidified their worth in time, an updating of that information became necessary in order to better capture the advances in this field.

The second edition is a substantial update of the first edition in terms of topical coverage, modeling approaches and application pool. New straight-axis flexible-hinge geometries are included here, alongside curvilinear-axis designs, which are dedicated each a separate chapter. Both hinge categories realize their final, often-times complex, configuration by combining basic (or primitive) segments in either series or parallel, and by utilizing a compliance matrix approach to formulate their elastic characteristics. The quasi-static response of flexible-hinge mecha-nisms is studied in two chapters: one describes the serial mechanisms and the other discusses the parallel mechanism architectures. The chapter formulating the dynamic model of flexible-hinge mechanisms has a comprehensive new sec-tion on hinge inertia that are derived by means of compliance-based shape func-tions, similar to finite element models. The finite element chapter incorporates a new section dedicated to circular-axis line elements. A miscellaneous chapter proposes a new section on straight- and circular-axis hinge precision of rotation, as well as new sections detailing flexible-hinge stress concentration, and actua-tion/sensing by means of piezoelectric multilayer active hinges and blocks.

The matrix approach is applied throughout this book to model all problems either by compliance-based methods or by finite element modeling.

The sense that a more application-oriented approach in this type of book would benefit the reader was materialized by numerous newly solved examples of flexible-hinge mechanism applications.
My sincere hope is that this new edition could be of real assistance to the researcher interested in designing flexible hinges and flexible-hinge mechanisms that operate in the small-displacement/deformation domain and utilize linear models.
I would like to express my profound gratitude to all my colleagues at University of Alaska Anchorage, Technical University of Cluj-Napoca (Romania) and Cornell University who have helped this research book shape up with their direct contribution and advice on the research projects we have been collaborating since the publication of the first edition of this book. I was also very fortunate to be able to exchange ideas, discover new perspectives and hands-on solutions while exploring flexible-hinge mechanisms with my University of Alaska Anchorage (former) students Paul Bilodeau, Raphael Wunderle, Tim Kirk, Josh Lazaro, Jesse  Wight-Crask, Collette Kawagley, Kaitie McCloud, Beth Steele, Dennis Kudryn and Jeff Leath.

My sincere thanks go to Jonathan Plant, former Mechanical Engineering and Applied Mechanics Executive Editor at Taylor & Francis/CRC Press, for patiently working with me over an extended period of time and gracefully offering me almost-endless deadline extensions to allow me to complete this manuscript. I am also indebted to Nicola Sharpe, Mechanical Engineering Editor at Taylor & Francis/CRC Press, for her prompt and professional support with finalizing this project.
Last but not least, I am beyond grateful to my wife Simona for her constant encouragement, patience and unwavering faith that I will somehow, sometime get to the end of this effort and fully return to more mundane activities – I would not have done it without her.

April 2020, Anchorage, AK