Control of an all-movable foreplane for a three surfaces aircraft wind tunnel model

Active Control of Three-Surface Aeroelastic Model

“…When active control deflects symmetrically canard foreplanes, control is related to fuselage-bending mode, and the ILAF control system appears very efficient for both DLR and VZLU foreplanes. The maximum damping, equal to 2.2%, is obtained for VZLU foreplane, at a speed equal to 35 m=s and for a gain equal to 10. It clearly appears that the only difference between the two canard configurations is the maximum value that allows obtaining the same amount of acceleration reduction, as both solutions almost come to the same achievement.…”

“…On this model, an aeroelastic wing has been designed to have its natural scaled frequencies close to the typical wing frequencies of an aircraft of this class. Into the framework of the 3AS project, the original X-DIA RPV has been modified to be used as a wind-tunnel aeroelastic model to investigate mainly the AAMFP concept [10] used to improve the benefits of the three-surface configuration [11][12][13][14] and described in the following section. Even if studying and optimizing aircraft configurations was not among the main goals of the research, an unconventional three-surface configuration has been adopted.…”

“…On such an innovative configuration, different aeroelastic concepts can be tested, but one among the variety studied during 3AS project, the AAMFP [10], is deeply investigated by means of either numerical models or wind-tunnel testing. The addition of allmovable control surfaces right on the nose cone of an aircraft, can lead to some benefits such as providing significant improvements in terms of gust alleviation, reduction of fuselage vibrations by active control, and minimization of overall trim drag taking aeroelastic deformations into account.…”

“…The specific control system has been implemented under Matlab Simulink. Specific details can be found in [10]. This system has the capability to actuate independently both canard surfaces, allowing both a common static trim of the model and also active control of fuselage symmetric bending modes (a symmetric rotation of the foreplane produces a lift sufficient to damp fuselage bending) as well as antisymmetric modes (in this case, antisymmetric rotation produces a torque to damp fuselage torsion).…”

High order harmonic balance applied to an aeroelastic T-tail model with a control surface freeplay

“…The T-tail unit considered in this study, Figure 1, is the one of the X-DIA, an aeroelastic model representative of a non-conventional three surfaces regional jet (called Target Aircraft), intensively investigated in the last few years at the Department of Aerospace Science and Technology, Politecnico di Milano DAST-POLIMI (see 2,3,4 ). …”