Experimental study on the modes of active truss

By using a 78-bars space truss, the configuration and properties of a linear active structure are studied experimentally, and the experiment technique for constructing an active structure is practiced. The active truss is constructed by using piezoelectric stack actuators and adopting linear quadratic optimal control in coupling mode space. The modal shapes and modal parameters are, measured for active truss and passive truss respectively on active truss is measured when it is under a random excitation. It is shown that the damping of an active structure increases as a result of the control means introduced. Meanwhile, difference of the mode is much great between the passive truss and the active one because the mode of the bar is controlled nearby the piezoelectric actuators.