PROJECT TITLE :

Highly Efficient Passive Thermal Micro-Actuator

ABSTRACT:

A passive thermal micro-actuator with large area specific work and massive displacement, fabricated of electroplated nickel on a silicon substrate is presented. The actuation relies on the thermal enlargement of beams in a V-formed geometry. Two V-formed beam stacks are aligned opposite to every different and are coupled to a lever transmission. The actuator exhibits low energy losses thanks to the deformation of the structure and can efficiently convert the thermally induced elastic energy into mechanical work. An analytical model considers these thermally induced mechanical energies and therefore the energy losses caused by the deformation of the material. The calculated deflections are compared with the measured ones and results of finite-part methodology simulations. The presented actuator operates utterly passive, relies only on temperature changes of the encircling surroundings, and exhibits a measured temperature-dependent linear deflection coefficient of $one.forty eight~mu textm$ /K with a simulated blocking force of $57~mu textN$ /K. The structure occupies an space of $2135 ,, times ,, 1831~mu textm^2$ and the realm specific work is calculated to be $21.7~mu textJ/textK^2/textm^2vphantom sum ^R^R$ , beating cutting-edge thermal actuators. As proof-of-concept, a passive micro-electro-mechanical systems temperature threshold sensor is fabricated, featuring the actuator and a bistable beam that switches between 2 stable positions when a specific threshold temperature is exceeded. [2014-0317]