초록 ▼

The present invention relates to an Active Control Surface Modal (ACSM) device that generates unsteady aerodynamic damping to alleviate aeroelastic structural instability, vibration and dynamic loads. An active control surface modal deformation is created by means of a pair of antagonistically activ

The present invention relates to an Active Control Surface Modal (ACSM) device that generates unsteady aerodynamic damping to alleviate aeroelastic structural instability, vibration and dynamic loads. An active control surface modal deformation is created by means of a pair of antagonistically activated actuators. Since the masses of upper and lower surface skins are lighter, the modal deformations can be activated at high frequencies that can encompass wide band spectrum of buffet, gust and flutter problem areas. An independent dosed loop active control system is used to activate the ACSM modes. Measured acceleration sensors are used as the feedback signals to compute the coefficients of the control law that is designed to suppress the dynamic environments such as buffet, gust and flutter. Then a computerized control system algorithm outputs a series of voltage signals that pass through power amplifiers to activate the actuators. Then the ACSM device generates unsteady aerodynamic damping in out-of-phase with the external (buffet/gust) or self excited air loads (flutter) to reduce or eliminate the undesirable dynamic effects on the aircraft. Some buffet analyses of a vertical tail, typical of a fighter aircraft, show 80 per cent reduction in peak stress, which amounts to an eight fold fatigue life extension of the vertical tail.

대표청구항 ▼

1. A control surface having a leading edge and a trailing edge and a spanwise extending spar rotatably hinged at its leading edge on an aerodynamic lifting surface comprising:an upper skin fixed to the spar of the control surface extending spanwise and extending chordwise from the leading edge of th

1. A control surface having a leading edge and a trailing edge and a spanwise extending spar rotatably hinged at its leading edge on an aerodynamic lifting surface comprising:an upper skin fixed to the spar of the control surface extending spanwise and extending chordwise from the leading edge of the control surface to the trailing edge of the control surface and having an outer surface and an opposed inner surface; a lower skin fixed to the spar extending spanwise and extending chordwise from the leading edge of the control surface to the trailing edge of the control surface and having an outer surface and an opposed inner surface; a plurality of first actuators mounted on the inner surface of the upper skin at spanwise spaced locations selectively operable for causing, in one instance, a range of convex chordwise curvatures of the outer surface of the upper skin and, in another instance, a range of concave chordwise curvatures of the outer surface of the upper skin; a plurality of second actuators mounted on the inner surface of the lower skin and juxtaposed at spanwise spaced locations selectively operable, antagonistic to the first actuators, for causing, in one instance, a range of concave chordwise curvatures of the outer surface of the lower skin and, in another instance, a range of convex chordwise curvatures of the outer surface of the lower skin; and an active modal control system including a controller for operating the plurality of the first and second actuators and thereby adjusting the outer contour of the control surface and thereby suppressing flutter, buffet, and gust loads to which the aerodynamic lifting surface is subjected.