Modeling and experimental modal analysis of active truss structure

In this paper, the dynamic model of an active truss structure configured two active piezoelectric members is established, and an experimental modal analysis is completed by means of d-SPACE control system. From the experimental results, it can be seen that the difference of modes of the active and passive trusses is remarkable. Under a proper control law, the frequencies, mode shapes and damping ratios of active truss are changed properly, because the modes of the members nearby two active piezoelectric members are restrained. It is worth mentioning that the lower-order damping ratios of active truss are larger than which of passive one. The larger damping ratio is favourable to structural vibration suppression, which is also verified by the comparison between the two transfer functions of active and passive truss. In a word, a well-configured active truss structure may improve its dynamic performances.