The active control of vibration for a beam subjected to multi-disturbances is investigated based on wave propagating suppression. In this control system, there are the same numbers of the sensors, the signal inputting...The active control of vibration for a beam subjected to multi-disturbances is investigated based on wave propagating suppression. In this control system, there are the same numbers of the sensors, the signal inputting to the controller and the disturbances, but there is only one controller. It is a local control system, the system parameters depend only on the characteristics of the structure bounded by the sensors and the controller, and we need not take into account. the boundary conditions and the properties of structures outside of this held. The system is efficient when a structure vibrates in middle and high frequency regions. Some control design rules are developed from the calculation results.展开更多
A new type of air bearing with flexure structure is introduced. The new bearing is designed for precision mechanical engineering devices such as mechanical watch movement. The new design uses the flexure structure to ...A new type of air bearing with flexure structure is introduced. The new bearing is designed for precision mechanical engineering devices such as mechanical watch movement. The new design uses the flexure structure to provide 3D damping to absorb shocks from all directions. Two designs are presented: one has 12 T-shape slots in the radian direction while the other has 8 spiral slots in the radian direction. Both designs have flexure mountings on the axial directions. Based on the finite element analysis (FEA), the new bearing can reduce the vibration (displacement) by as much as 8.37% and hence, can better protect the shafts.展开更多
基金The project supported by the National Natural Science Foundation of China Post Doctorate Science Fund of China
文摘The active control of vibration for a beam subjected to multi-disturbances is investigated based on wave propagating suppression. In this control system, there are the same numbers of the sensors, the signal inputting to the controller and the disturbances, but there is only one controller. It is a local control system, the system parameters depend only on the characteristics of the structure bounded by the sensors and the controller, and we need not take into account. the boundary conditions and the properties of structures outside of this held. The system is efficient when a structure vibrates in middle and high frequency regions. Some control design rules are developed from the calculation results.
基金Selected from Proceedings of the 7th International Conference on Frontiers of DesignManufacturing(ICFDM'2006)This project is partially sup-ported by the Research Grant from the Hong Kong Watch Manufacturers Association the Federation of Hong Kong Watch TradeIndustry Technology Commission China(No.ITS/001/05).
文摘A new type of air bearing with flexure structure is introduced. The new bearing is designed for precision mechanical engineering devices such as mechanical watch movement. The new design uses the flexure structure to provide 3D damping to absorb shocks from all directions. Two designs are presented: one has 12 T-shape slots in the radian direction while the other has 8 spiral slots in the radian direction. Both designs have flexure mountings on the axial directions. Based on the finite element analysis (FEA), the new bearing can reduce the vibration (displacement) by as much as 8.37% and hence, can better protect the shafts.