fatigue testing, mechanical stability, microactuators, microswitches


A new class of fully compliant bistable mechanisms with the added benefit of integrated self-retraction has been developed (hereafter identified as Self-Retracting Fully compliant Bistable Mechanism or SRFBM). A technique using tensural pivots to manage compressive loading in compliant mechanisms is introduced and implemented in the SRFBM. The elimination of traditional kinematic joints and their associated clearance allows a total displacement between stable positions of 8.5 m, and the mechanism size is less than 300 m square when using 2.0 m minimum line widths. Maximum actuation force is approximately 500 N. The SRFBM's small linear displacement and reasonable actuation force facilitate integration with efficient thermal actuators. Furthermore, fully compliant mechanisms allow greater freedom in fabrication as only one mechanical layer is needed. Systems with on-chip actuation have been fabricated and tested, demonstrating bistability and on-chip actuation, which requires approximately 150 mW. A single fatigue test has been completed, during which the SRFBM endured approximately 2 million duty cycles without failure.

Original Publication Citation

Masters, N.D. and Howell, L.L., “A Self-Retracting Fully Compliant Bistable Micromechanism,†Journal of Microelectromechanical Systems, Trans. IEEE and ASME, Vol. 12, No. 3, pp. 273-28, 23.

Document Type

Peer-Reviewed Article

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Ira A. Fulton College of Engineering and Technology


Mechanical Engineering