An in-plane, large-stroke, multipole electromagnetic microactuator realized by guideways stacking mechanism

Publication date: Available online 17 August 2019Source: Sensors and Actuators A: PhysicalAuthor(s): Dong Han, Tadahiko Shinshi, Noriei Azuma, Shogo KadotaAbstractIn the application of cell phone cameras, it is essential to design optical image stabilizers with tiny size, in-plane motion and large stroke. Previously, small sized voice-coil actuators utilizing assembled magnets have been developed to achieve displacements up to 500 µm. Here, we propose a novel MEMS electromagnetic actuator employing a multipole permanent magnet with a finely pitched chessboard pattern and stacked multilayer Si-based guideways, enabling us to obtain a large stroke at low driving voltages. The magnet, which has multiple poles (pole number: 36) and a fine pitch (magnetization pitch: 1 mm), is realized by a combination of laser assisted heating and an external magnetic field, utilized to enhance the magnetic strength. For the support mechanism, stacked multilayered Si-based guideways are adopted to reduce the friction in the driving x- and y-directions and increase the rigidity in the non-driving z-direction. Driving experiments showed the proposed microactuator was capable of both independent 1-DOF motion and simultaneous 2-DOF motion with driving frequencies varying from 1 to 15 Hz. For the independent 1-DOF motion, an approximately straight line trajectory with a maximum stroke of 760 µm was obtained with an AC of 160 mA at a frequency of 1 Hz. In the simultaneous 2-DOF motion, a ...

Source: Sensors and Actuators A: Physical - August 18, 2019 Category: Physics Source Type: research