Accurate Sensorless Multistable Microsystem With a Single Actuator

The layout of the multistable microsystem and SEM image for the microfabricated multistable microsystem.

The design of microdevices involves several limitations and the corresponding miniaturization is challenging. Innovative approaches and more intelligent structures are required to develop compact devices and facilitate miniaturization. A multistable device is developed in this work. The miniaturization of this device is pushed to the limit by using a single actuator for switching in different directions and by excluding sensors while keeping positioning accuracy. This work is published in Frontiers in Mechanical engineering (doi: 10.3389/fmech.2022.825470).

The multistable microsystem is developed to realize the accurate positioning on the microscale by using a single actuator, without any positioning sensors. The microsystem has a compact design and is fabricated on a monolithic chip based on Micro-ElectroMechmechanica System (MEMS) fabrication process. The mobile part in the multistable microsystem 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. The working principle and the operation of fabricated prototypes are demonstrated in the following video.