Nonlinear Modeling and Control Design of Active Helicopter Blades

The paper presents the theoretical basis for the simulation of active helicopter blades. The analysis of active helicopter blades is based on models for the structure, aerodynamics, actuation and sensing. For simulation and analysis purposes, the blade structural model is discretized in space using a Galerkin approach. The eect of the integral actuation enters the beam model via an active beam cross-sectional analysis. A 2-D incompressible, inviscid, quasi-steady aerodynamic model is coupled to the active structural model. The resulting nonlinear model of high order is reduced using the aeroelastic modes of the blade. Finally, a nonlinear controller is obtained by cancelling the nonlinearities and applying an energy optimal LQR design to the resulting linear plant.

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