Wireless Microactuator Using Temperature-Sensitive Magnetic Material for Remote Operation

抄録

This paper presents a novel wireless microactuator that utilizes a temperature-sensitive magnetic material (TSMM) for remote operation. The microactuator consists of a TSMM part, permanent magnets, and a laser light source that heats a specific area of the TSMM part. The driving principle is based on a decrease in the saturation magnetic flux density of the TSMM with increasing temperature, which enables continuous force generation and movement. Two prototype mechanisms, namely a microgripper and a rotary micromechanism, were designed and fabricated to demonstrate the capabilities of the proposed actuator. The prototype microgripper was designed such that the finger carrying the microobject and the actuator environment were separated by a thin glass. The finger and the actuator were connected by magnetic coupling such that the microobject and the actuator could be used in their respective environments. The prototype of the rotary micromechanism was designed to consist of a small number of parts with simple shapes. Magnetic field analysis showed that the microgripper generated a gripping force of 2.7 mN, and the rotary micromechanism generated a torque of more than 50 µNm. The experimental results confirmed the continuous movement of the two prototype mechanisms under laser irradiation. The motions of the actuator and the magnetically coupled finger in the microgripper were measured, and the differences in motion were confirmed. The motion of the rotary micromechanism was measured under three different laser powers, and it was confirmed that the higher the power, the faster the TSMM ring rotated.