Structural displacement tracking by eigenstrain actuation: Computational and experimental validations

In the present paper, we seek for a control actuation, which, when being subjected together with some imposed transient force loading, produces a desired (prescribed) displacement field in a linear elastic structure. In our study, special emphasis is laid upon smart structures, i.e. on a control actuation by eigenstrains induced via piezoelectric or thermal actuators, or via analogous effects, such as magnetostriction or pre-stress. It is shown that the actuation stresses due to the distributed control eigenstrains must satisfy certain quasi-static equilibrium conditions, where auxiliary body-forces and auxiliary surface tractions are to be taken into account. The latter auxiliary loading can be directly computed from the imposed loading and from the desired displacement field to be tracked. Hence, despite we are dealing with a dynamic problem, a straightforward computation of proper actuator distributions can be performed in the framework of quasi-static equilibrium conditions only. © 2007 Civil-Comp Press.