REDUCTION OF HELICOPTER VIBRATIONS THROUGH CHAOTIC CONTROL

Vibrations, particularly those generated by the rotor, affect all aspects of helicopter design. It has recently been demonstrated that helicopter rotor vibration comprises a periodic "component" and a chaotic "component." The periodic part can be eliminated using Higher Harmonic Control (HHC), leaving the chaotic component. Until recently, it was considered unfeasible to further reduce the vibrations. A new method, called the OGY technique, has been discovered which permits many chaotic systems to be controlled. In the proposed program, the OGY technique will be extended and combined with HHC to essentially eliminate rotor-generated vibrations in helicopters. In Phase I, acutal helicopter vibrations data will be analyzed to prove that the chaotic vibrations are controllable. This program will be performed with the participation of the Boeing Helicopter Company, who will provide proprietary vibration data. Phase II will include a demonstration of combined HHC and chaotic control in actual helicopter testing, wind tunnel testing, or through numerical simulation.