Cover Page

Harnessing Bistable Structural Dynamics

For Vibration Control, Energy Harvesting and Sensing

Ryan L. Harne

The Ohio State University

Columbus, Ohio, USA



K.W. Wang

University of Michigan

Ann Arbor, Michigan, USA













This book describes a recent perspective that seeks to strategically harness the unique dynamics of bistable structural systems for engineering advances, with focus on the three technical areas of vibration control, energy harvesting, and sensing.

When a structural system exhibits two statically‐stable configurations, it is said to be bistable. This class of structures has been employed in various mechanical, civil, marine, and aerospace engineering applications for many years. The bistable components include arches and post‐buckled beams/columns, panels or shells having a shallow curvature, and curved microbeam or dome diaphragm transducers, to name just a few examples. In many historical assessments, it was undesirable for the bistable structure to “snap” to the second state of static equilibrium – a phenomenon referred to as snap‐through – because the consequence might be unfavorable to the health and performance of the overall engineered system. Thus, the structures or materials were used in ways to avoid static or dynamic loading (e.g., pressure on a shell) that could cause the bistable system to switch from the original, stable configuration to the other stable equilibrium (e.g., an inverted shell).

It is from such a perspective that the focus of this book departs. Recently, researchers have been challenged to reconsider bistable structural systems within a variety of emerging engineering contexts. Many scientists and engineers have discovered and explored the dynamics of bistable structures that may be deliberately exploited to the advantage of certain applications. Innovative ideas have been proposed to intelligently induce snap‐through behaviors such that the performance of the overall system is enhanced and/or new functionality is realized. This new spirit of engineering system development is the foundational viewpoint of this book: harnessing bistable structural dynamics.

The new ideas have been found to be well‐suited for many applications across a variety of engineering disciplines. Among them, researchers have particularly investigated the exploitation of bistable structural dynamics in the areas of (i) vibration control, (ii) vibration energy harvesting, and (iii) sensing and detection. In the first area, the dynamics of bistable devices integrated with the structural system are used so as to isolate, dissipate, or reactively attenuate the input energies that excite the system. Depending on the performance objective, the multi‐faceted dynamics of the bistable members are strategically employed to best control the vibrations and improve the operational integrity of the system. The aim of energy harvesting is to electromechanically convert ambient vibrations into usable electrical power resources. To this end, maintaining persistent snap‐through behaviors is a common aim because of the large dynamic mechanical and electrical response amplitudes that they induce in the energy harvesting systems. Hence, the energetics of snap‐through promotes a significant potential for energy conversion. In the context of sensing and detection, the ability to recognize small changes in monitored parameters, which represent time‐varying system characteristics, is critical in providing the earliest indicator of structural change. Thus, by harnessing the sudden transition between low amplitude oscillations around a stable equilibrium to energetic snap‐through vibrations spanning the static equilibria, bistable dynamics‐based detection strategies have been found as promising, novel approaches well‐suited for a variety of sensing contexts.

We are indebted to financial support from sponsors in order to conduct and document the research included in this book. Parts of the research were supported by grants from the Air Force Office of Scientific Research, the Defense Advanced Research Projects Agency, the National Science Foundation, by the University of Michigan Collegiate Professorship Fund, and by funds from the Department of Mechanical and Aerospace Engineering at The Ohio State University. We also recognize the contributions from our graduate students and co‐workers so that the breadth of research topics in this book may be so comprehensively investigated. These individuals include David Johnson, Jinki Kim, Fabio Semperlotti, Manoj Thota, Zhen Wu, and Kai Yang. In addition, we wish to acknowledge our many colleagues within the professional communities of adaptive materials and structures, dynamics and vibration, energy harvesting, structural sensing and health monitoring, and systems and controls who have cultivated a vigorous environment of search and discovery within which we have enthusiastically undertaken and compiled the efforts of this book. Finally, our deepest appreciations go to our families and loved ones for their tremendous support throughout the years.

Ryan L. Harne
Columbus, Ohio, USA

K. W. Wang
Ann Arbor, Michigan, USA