This paper on the reports design, fabrication and position monitoring of a micro electromagnetic linear actuator. The actuator consists of stator, slider, guide, sensors and affiliated jigs. Actuation is achieved through ampere force between two phase micro-coils (copper) on the stator and permanent magnets (thick NdFeB film) on the slider. During the slider’s movement in the guide slot, tunnelling magneto-resistance (TMR) sensors are utilized to sense the magnetic field to realize position monitoring. TMR is chosen because it owns advantages of small size, large sensitivity and easy integration with micro devices. Purpose of this research is to report the micro fabrication of thick magnet films and testify the possibility of using TMR as position monitoring sensors. Actuators are fabricated by micro-electro-mechanical system process (stator and guide) and precise machining (slider and jigs). Surface magnetic field generated by the slider, driving characteristics of the actuator as well as the position monitoring capabilities of TMR elements are simulated and experimented, respectively. The slider attains 60 mm s⁻¹ speed by sinusoidal input signal at 300 Hz frequency and 0.2 A current magnitude. Actuation bandwidth is between 300 Hz and 500 Hz at open loop condition. The maximum position monitoring error in present work is 2.2% with 101 μm value for 4.5 mm stroke.

本文对微型电磁线性致动器的设计，制造和位置监控进行了报道。执行器由定子，滑块，导轨，传感器和附属夹具组成。通过定子上的两相微线圈（铜）和滑块上的永磁体（厚NdFeB薄膜）之间的安培力来实现致动。在滑块在导槽中移动期间，利用隧道磁阻（TMR）传感器感应磁场以实现位置监视。选择TMR是因为它具有体积小，灵敏度高以及易于与微型设备集成的优点。这项研究的目的是报告厚磁体膜的微细加工，并证明使用TMR作为位置监测传感器的可能性。执行器是通过微机电系统工艺（定子和导向器）和精密机加工（滑块和夹具）制造的。分别模拟和试验了由滑块产生的表面磁场，致动器的驱动特性以及TMR元件的位置监视功能。滑块达到60毫米s^-1正弦输入信号在300 Hz频率和0.2 A电流幅度下的速度。在开环条件下，驱动带宽在300 Hz至500 Hz之间。当前工作中的最大位置监视误差为2.2 mm，4.5 mm行程的101μm值。