Abstract: In this paper, a high-precision thermal linear micro actuator ( LMA ) with a large travel range is analyzed, simulated and presented. Physical functions can be performed by MEMS thanks to micro-actuators. The operation of various types of micro-actuators in many applications has been successful. There are two perspectives to categorize micro-actuators one focused on driving forces and the other on mechanisms. Electric, magnetic, and flow fields can be utilized to generate force in the space between stationary and moving parts. The intrinsic actuation capabilities of materials like piezoelectric, magnetostrictive, and photo stretched materials also can be used in them. Changes in shape or volume caused by thermal expansion and phase transformations such as the shape-memory effect and bubble formation are another important ways to reach a deformation in these types of actuators. In our proposed LMA , electro-thermal technique has been selected. The main components of the electro-thermal LMA proposed are substrate, slider, stopper, and forks. The slider is a long rectangle beam placed on a rail so that can move bidirectional, either up-ward or down-ward. A complex interesting technique, by using the stoppers and forks, results bidirectional movement of the slider. The stopper consists of arrayed electro-thermal chevrons ( EC ) and springy clutch. By applying a DC voltage of 1.5 V to the Red fork's ECs arrays, the minimum step size approximately 20 μm is achieved. Repeating steps sequentially generate a travel range of about 2 mm. For all simulations, the ANSYS software has been used. The LMA has the ability to displace heavy loads linearly and accurately. Minimum step size and large travel range of the LMA proposed make it useful to be used for Mirror Shape Correction application.

Keywords: MEMS, Mirror shape correction, Linear micro actuator ( LMA ), Electro-thermal chevrons ( EC ), The slider, The stopper, The forks, The springy clutch.
__________________________________________________________________________________________