Accurate Sensorless Multistable Microsystem With a Single Actuator

Abstract

A compact and monolithic multistable microsystem was developed to realize the accurate positioning on the microscale by using a single actuator, without any positioning sensors. The mobile part can be maintained in several stable positions at rest with accurate intermediate steps and a high stability margin at each position. Switching between stable positions can be performed in both directions on one axis by using a single actuator. Using the mechanical intelligence encoded in the internal mechanisms, the mobile part position can be switched one step forward or back to the initial position through a single activation of the actuator. Multistable devices were designed and fabricated based on the working principle, and their satisfactory operation, with effective holding at stable positions and switching in two directions, was experimentally demonstrated.

Near-zero stiffness accelerometer with buckling of tunable electrothermal microbeams

“…are widely used in MEMS as compliant bistable mechanisms. Several mechanisms with interesting behavior at small and large scales have been developed, relying on the special stiffness behavior of pre-shaped beams 27 , including negative stiffness mechanisms 28 , zero-force mechanisms 29 , tunable stiffness mechanisms 30 , large-stroke mechanisms 31 , metamaterials 32 , safe manipulation 33 , accurate positioning 34 , and high sensitivity sensors 21 .…”