Table of Contents

Introduction

Flexure bearing importance

Flexible element classification

Book goals

Topic delimitation 


BASIC FLEXURES

Underlying theory

Basic assumptions

Allowable deflections

Stiffnesses

Flexure joint elements

General considerations

Leaf springs

Rods

Torsion bars

Circular notch hinges

Linear translation bearings

Two parallel leaf spring stage

Over constrained stage with four parallel leaf springs

Four prismatic notch hinge stage

Four circular notch hinge stage

Conclusion on linear translation bearings

Rotational bearings

Separate cross spring pivot


Joined cross spring pivot


RCC pivot with two leaf springs


RCC pivot with four notch hinges


Cross pivot with four notch hinges 


Comparison of the pivots

Radial loads

Over constrained pivot with three leaf springs

FLEXURE MECHANISMS

Flexure structures

Kinematics

Choice of materials

Working envelope

Stiffnesses

Modular design of flexure mechanisms

Introduction

Concept of modular kinematics

Reduced solution catalogue for ultra-high precision

Mechanical design of the building bricks

Case study: 5-DOF ultra-high precision robot

Ultra-high precision parallel robots family

Conclusion

Final Note

Rectilinear flexure mechanisms

Introduction

Rectilinear Kinematics

Sarrus guiding mechanism

13-hingestage mechanism

Analysis and comparison

Application to the watt balance

Conclusions

Examples of planar mechanisms used for out-of-plane functions

Introduction

Example of design problem of an active cardiac stabilizer

Exploiting the vicinity of singularities

Optimization of the spherical compliant joint

Exploiting the singularities of parallel mechanisms

Selection of an actuation mechanism

Integration of the three mechanisms in the two planes

Conclusions

About the Author

Simon Henein was born in 1973. He obtained an engineering degree at the Ecole Polytechnique Fédérale de Lausanne (EPFL) in 1996 and went on to complete his doctorate at the EPFL in 2000. In 2001, he published the book "Conception des guidages flexibles" which has become a reference in precision engineering. He then joined the Centre Suisse d'Electronique et Microtechnique (CSEM), Neuchâtel, Switzerland, where he conceived and developed mechanisms for robotic, aerospace, medical and watchmaking applications. He pursued his research career at the Paul Scherrer Institute, Villigen, Switzerland, where he developed instruments for the Swiss Light Source Synchrotron (SLS). Since 2012 he is associate professor in microengineering at the EPFL, holder of an endowed chair in micromechanical and horological design (Instant-Lab).





Lennart Rubbert was born in 1984. He studied mechatronics at Institut National des Sciences Appliquées (INSA) in Strasbourg where he got an engineering degree in 2009. He also obtained in 2009 a Master degree in Robotics and Control at the University of Strasbourg. He completed his Ph.D. on the design of compliant mechanisms for surgical robotics in 2012 at the University of Strasbourg. From 2013 to 2015 he performed his postdoc at Instant-Lab (EPFL) with Prof. Simon Henein. In 2015, he became assistant professor at INSA de Strasbourg in the mechanical department and is also a researcher and scientist at ICube in the Control Vision and Robotic team.


Florent Cosandier was born in 1984. He obtained his master's degree in engineering from the Ecole Polytechnique Fédérale de Lausanne (EPFL) in 2007, after completing his studies during the master thesis at the Chinese University of Hong Kong (CUHK). In 2013, he obtained his Ph.D. at the EPFL, for which he was awarded the Prix Omega scientific award. He then joined the Swiss Federal Institute of Metrology (METAS) for a postdoctoral position, where he developed precision mechanisms for the new Swiss Watt Balance. In 2014, he joined the Centre Suisse d'Electronique et Microtechnique (CSEM) in Neuchâtel, Switzerland, where he currently develops precision flexure mechanisms for watchmaking, aerospace and metrology applications.





Murielle Richard was born in 1984. She obtained her Master of Science in Microengineering at the Ecole Polytechnique Fédérale de Lausanne (EPFL) in 2008, with a special focus on robotics, autonomous systems, machine learning and mechanical design. In 2012, she completed her Ph.D. in Manufacturing Systems and Robotics in the same university. Her research topics covered high-precision and industrial robotics, as well as compliant mechanisms. She presently works at ETA Manufacture Horlogère SA, where she designs high-precision and compliant mechanisms for manufacturing and assembly systems. Her broader activities include industrialization of new products, development of new assembly machines and continuous improvement of production lines.