Active vibration control of automotive like panels 2008-36-0576
Automotive panels can be great transmitter of undesired sound from external sources. The ability of controlling the noise and vibration performance of such panels is critical to the perceived quality of a vehicle. Passive vibration systems are currently used in vehicles, but they tend to be heavy in nature and capable of covering only a frequency range above 100-200 Hz. Active vibration control is a potential alternative to passive control. Its cost and adaptability of an active system has been the primary concern for implementation in the automotive sector. Recent developments in the control implementation and lower cost of electronics in general have made the gap between active and passive much smaller than before. An active vibration control has been developed and demonstrated into an automotive-like panel. Such panel was sized to represent a door of a military vehicle. Several excitation sources were considered and included engine excitation, road excitation and blast excitation due to the military design constraints. The active vibration control system is comprised of strain sensors, piezoelectric actuators, a control system and a power amplifier to drive the control actuators. Several control strategies were used depending on the source of excitation. Once of the primary features of all the control strategies used was their adaptability to the change in conditions. A 10 to 15 dB vibration reduction was obtained over the frequency range of interest. As the physically conditions changed (shift in frequency), the control algorithm adapted to the new conditions and vibration reduction could be obtained achieving the same level of performance as during the initial target. The cost of the solution was maintained to a minimum, and its potential production costs for automotive quantities was estimated to be in the order of few tens of dollars (US).