Beam Actuation Concepts

Sealed Capsule Expansion Microvalves In 1987, Zdeblick and Angell [3] first proposed the concept of the sealed capsule expansion (SCE) valve, which utilized the thermal expansion of a trapped liquid to actuate the valve instead of the buckling of a beam or membrane. Later, a family of sealed capsule expansion valves trademarked as the FluistorTM was developed by Redwood Microsystems. Generally, in an SCE microvalve, there is a small cavity with trapped liquid which has a low boiling point and/or a high expansion coefficient. When the liquid is heated, it expands and closes the valve. When it is cooled, it shrinks and opens the valve. 

In Section 2.5.1, the various beam actuation concepts are presented using the classification illustrated in Figure 2.10. Analogously applying to sensing, we distinguish between normal (lengthwise) and shear mode actuation in the plane of the wall as well as between its consistent and sectorial application across the plane of the cross-section. 

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