ACTIVE NOISE CONTROL

THE PROBLEMS OF ATTENUATING DUCTED NOISE AND DISTRIBUTED NOISE ARE ADDRESSED USING ACTIVE NOISE CANCELLATION TECHNIQUES. FOR DUCTED NOISE, A COMBINATION OF COMMERCIAL ANC EQUIPMENT WITH LOW PRESSURE DROP MUFFLERS IN AN SVS PROPRIETARY CONFIGURATION WILL BE EXAMINED. COST AND PERFORMANCE TRADES BETWEEN THE ACTIVE CONFIGURATION AND PASSIVE MUFFLERS WILL BE MADE AND AN EXPERIMENT WILL BE DESIGNED FOR PHASE II TO VALIDATE THE PREDICTIONS. FOR DISTRIBUTED NOISE, AN ACTIVE SOUND BARRIER DESIGN WILL BE OPTIMIZED USING BOTH FEEDBACK AND ADAPTIVE FEED FORWARD CONTROLS. THE SENSOR AND ACTUATOR CONFIGURATIONS WILL BE OPTIMIZED AND PERFORMANCE WILL BE ASSESSED USING A DETAILED SIMULATION. THE SIMULATION WILL DRAW ON TWO EXISTING SIMULATIONS. THE FIRST IS A SIMULATION OF FEEDBACK CONTROL OF A TWO DIMENSIONAL STRUCTURAL SURFACE WITH DISTRIBUTED ACTUATORS. THE SECOND IS A SIMULATION OF ADAPTIVE FEED FORWARD CONTROL USED IN CONJUCTION WITH FEEDBACK CONTROL WHICH HAS PROVEN TO BE ROBUST TO NOISE AND FEEDBACK FROM THE ACTUATOR TO THE FEED-FORWARD SENSOR. AN EXPERIMENT WILL BE DESIGNED FOR PHASE II TO VALIDATE THE SIMULATION AND THE PREDICTED PERFORMANCE.