Design of a large displacement thermal actuator with a cascaded V-beam amplification for MEMS safety-and-arming devices

The design, fabrication and characterization of a large displacement thermal actuator with a cascaded V-beam amplification for MEMS safety-and-arming (SA) devices are presented. The device is comprised of two V-shape electrothermal actuators, a cascaded V-beam amplification and two mechanical sliders. Compared with conventional lever amplifications, the vertical anti-acceleration stiffness of V-beam amplifications is much larger, which can meet the need of high-acceleration weapons. The special design of two symmetric mechanical sliders can double the displacement to ensure the MEMS SA device in armed state. The whole device is fabricated on a SOI wafer and fabrication process is introduced. Under an applied voltage of 15 V, the displacement of the device is 231.78 μm with consuming power of 5.10 W and response time of 16 ms. The chip size of the actuator is about 4 mm × 5 mm × 0.5 mm. The proposed actuator possesses outstanding performance in miniaturization, low cost and easy integration with other parts of MEMS SA devices.