ACTIVE STRUCTURAL CONTROL SYSTEM AND METHOD INCLUDING ACTIVE VIBRATION ABSORBERS (AVAs)

摘要

An Active Structural Control (ASC) system (10) and method which includes a plurality of Active Vibration Absorbers (AVAs) (40) attached to a yoke (32) included within a pylon structure (28) preferably comprising a spar (38) and a yoke (32) which is located intermediate between an aircraft fuselage (20) and an aircraft engine (18) for controlling acoustic noise and/or vibration generated within the aircraft's cabin (44) due to unbalances in the aircraft engine (18). The ASC system (10) includes a plurality of error sensors (42 or 63) for providing error signals, and at least one reference sensor (49 or 50) for providing reference signals indicative of the N1 and/or N2 engine rotations and/or vibrations, and a preferably digital electronic controller (46) for processing the error and reference signal information to provide output signals to dynamically vibrate the plurality of AVAs (40) attached to the yoke (32). The AVAs (40) preferably act in a radial, tangential, or fore and aft directions and may be located at the terminalend and/or at the base portion of the yoke (32). Further, the AVAs (40) may be Single Degree Of Freedom (SDOF) or Multiple Degree Of Freedom (MDOF) and may be tuned to have a passive resonance which substantially coincides with the N1 and/or N2 engine rotation and/or vibrations. In another aspect, reference signal processing is described which includes a modulo counter, a lookup table, and a digital IO device.