DESIGN AND FABRICATION OF MICROFLAP ACTUATORS FOR STEERING OF MICRO AIR VEHICLES

摘要

This paper presents the design, analysis, and fabrication of an array of microflap actuators that can produce a substantial aerodynamic force for course corrections of Micro Air Vehicles (MAVs) and low speed projectiles. In the past, several actuation principles, including microjet, magnetic and bubble actuators, and flapping wings have been proposed, and had varying degrees of success. In this paper, we discuss the benefits and drawbacks of past attempts, and the technology that can be used to address the microflap steering problem. We propose a hybrid microflap actuation scheme that combines two types of actuators including: 1) a MEMS fabricated "active" microactuator connected to a microflap, and 2) a "passive" fluidic channel system that harvests the potential energy in the high pressure field on the leading edge of the MAV or high speed projectile to achieve a desired deflection. An array of microflap actuators was prototyped using silicon MEMS fabrication and microassembly. A Silicon On Insulator (SOI) wafer with 100 micron thick device layer was used to as a substrate material to fabricate microflap structures with springs. Front and back side DRIE process was used to etch and release the microstructures including microflaps. Then, the microactuator was assembled on top of the microflap. The static and dynamic behaviors of a microflap were measured using a laser displacement sensor and were compared to the analytic model. In the near future, a prototyped microflap will be tested inside of a wind tunnel to measure the lift and drag at various air speeds.