Hybrid active/semi-active modal control of smart structures

Smart structures controlled by active algorithms proved their high efficiency. But active control requires external energy and heavy amplifier which strongly limit the applications in the transportation field. An alternative to active control is given by semi-active control which does not require operative energy but which is less efficient than active control. The proposed hybrid control associates the active control with semi-active control in order to benefit from the respective advantages of both methods. This hybrid control is intended to control vibration modes with the same performances than active control while reducing significantly the operative energy. An application on the second mode of clamped-free smart beam is presented. The results show that this new control approach appears to be able to decrease the required external energy and to reduce the power and consequently the weight of the active control amplifiers while maintaining the same damping performances. This control can be used, for example, in the transportation field to improve the lifetime of systems which use smart structure.