ON THE ROBUST CONTROL OF NONLINEAR AEROELASTIC RESPONSE OF AN AIRFOIL
Natália C. G. de Paula1; Daniel A. Pereira1; Flavio D. Marques1
1 Engineering School of São Carlos, University of São Paulo
doi:10.20906/CPS/COB-2015-0568
Resumo
This work is related to the control of aeroelastic response in typical section where nonlinear structural effects is present. This investigation admits the development of numerical and experimental approaches to exam robust alternatives to control laws in aeroelastic applications. Typical section model in pitching and plunging displacements is considered, where a hardening nonlinear effect in pitch stiffness is included to the problem. Such effect leads the system to typical nonlinear responses and flutter connected to limit cycle oscillations. Moreover, subcritical bifurcation can also be associated. After numerical model validation, active control can be achieved. Robust control laws are considered admitting first the concept of linear optimal designs, followed by applying fuzzy logic control as a nonlinear approach. Control systems are, then, implemented to the experimental apparatus to check on their features and efficiency on controlling nonlinear aeroelastic responses and suppressing flutter phenomenon. As a source of actuation to the active control problem, piezoelectric patches are used. The performance of this kind of actuation method will also be examined in this investigation.
Palavras-chave: Aeroelasticity; Robust control; Fuzzy logic; piezoelectric; active control; optimal control