Design and Testing of a Rotary Wing MAV with an Active Structure for Stability and Control

摘要

The design and testing of a rotary wing Micro Aerial Vehicle (MAV) using an active, flexible structure for stability and control is discussed in this paper. The vehicle configuration consists of a set of coaxial, counter-rotating rotors independently driven by two coaxial electric motors. Multi-functional structures are used as the primary structural components with the ultimate goal of vehicle weight minimization. Light-weight carbon fiber composite beams comprise the MAV structure. The inherent flexibility of the structure enables the realization of a rotor system with marginal passive stability and minimal complexity. Thin, lightweight shape memory alloy (SMA) wires are incorporated in the structure. The wires serve as lateral control actuators as well as a portion of the structural support. Structural vibration is mitigated through the integration of constrained viscoelastic damping material into the composite structural elements. In addition, power is provided to the upper electric motor through conduits integrated into the composite structural elements. A lithium polymer battery pack is used to power the vehicle and serves as the structural support for the electronics and sensors. Preliminary tests show that the SMA actuator has a bandwidth of approximately 1 Hz and can provide sufficient authority for lateral control.