Semiactive Control of Multimode Vibratory Systems Using the ILSM Concept

The Identically Located Sensor and Manipulator concept involves deriving a control force from measurements of motion at the force generator mounting point. A semiactive force generator may be made from a damper whose force-velocity law can be varied in response to a signal. These two ideas are discussed and the advantages from combining the two ideas for controlling several normal modes for distributed parameter structures are presented. Computer simulation results comparing active, semiactive, and passive suspensions for a beam-like structure subjected to broadband noise excitation are given to illustrate the performance capability of each system.