Combined passive and active helicopter main rotor morphing for helicopter energy save

Abstract

In this article, passive morphing and active morphing approaches are combined to save more helicopter flight control system (i.e., FCS) energy. For this purpose complex, physics-based, control-oriented nonlinear helicopter models are benefited. A specific variance-constrained control strategy, namely Output Variance-Constrained Control (i.e., OVC) is applied for helicopter FCS. Control energy savings using passive, active and combined morphing approaches are examined. Parameters of helicopter FCS and combined morphing helicopter design parameters are simultaneously optimized using a stochastic optimization method, namely simultaneous perturbation stochastic approximation (i.e., SPSA). To observe energy save, closed-loop analyses are done. Finally, robustness of combined morphing helicopter with respect to (w.r.t.) the modeling uncertainties is examined.