Active vibration control system using gyroscope for structures

Abstract

The active control system is one in which an external source powers control actuators that apply forces to the structure in a manner calculated by control algorithms. These forces can be used to both add and dissipate energy in the structure. The most commonly used active control device for civil engineering structures is the active mass damper system. In the last two decades, many other active devices have been developed and investigated by many researchers for civil engineering applications, however, most of these de-vices are based on the active mass damper which apply shear forces to the structure. This dissertation proposes a new, compact and effective active control device to reduce structural responses due to seismic and wind loads. The gyroscope system utilizes the gyroscopic moment for vibration suppression of the structure with predominant bending modes. To verify the control performances of the proposed active control device, gyroscope system, numerical analyses for a scaled cantilever beam and a real structure is performed and the results are compared to those of active mass damper. Moreover, the gyroscope system using linear optimal control strategy for vibration suppression of the cantilever beam subjected to ground accelerations has been experimentally investigated by a shaking table test. The gyroscope system is commonly used for the attitude control of an unstructured object, for example, when we need to lift up or carry a beam with crane, the attitude of beam turn aside or may be rotated while the crane is moving. These need the attitude control to reject the effect due to the unwanted external force like winds. The gyroscope system also can be used for vibration control for structured objects like buildings, towers, bridges. To confirm the possibility of gyroscope system as a control device, the linear optimal control method using gyroscope systems and active mass damper are implemented for a scaled cantilever beam subjected to ground acceler...