Controlling plate vibrations using piezoelectric actuators

Launch vehicles often experience severe vibration problems during the ascent phase due to intense acoustic fields and mechanically transmitted disturbances. These disturbances are characterized by a large number of resonances over a wide-band frequency spectrum. The payloads inside the launch vehicle must be designed strong enough to withstand these structural vibrations. Passive isolators are used to isolate the payloads from the vibrating structure but this type of isolation has no effect on the acoustic excitations. This study focuses on methods for achieving active damping on plate structures by means of piezoelectric actuators (PZTs). An experiment was conducted using PZT actuators and accelerometers mounted on a rectangular plate with an active damping controller implemented on a 486 computer. Two control design methods were evaluated for this application: the H/sub /spl infin method and rate feedback.<>