Adhikari, S.
Proceedings of the 23rd International Modal Analysis Conference
(IMAC-XXIII), Orlando, Florida, USA, February 2005.
Modal actuators and sensors may be used to excite or measure either single modes or combinations of modes, and may be implemented using either discrete transducers or continuous, distributed transducers produced using piezo-electric materials. Continuous, distributed transducers require less processing and thus simple controllers may be employed. This paper considers the design of continuous transducers for plate structures. For beam structures the width of the transducer may be varied, whereas for a plate the options are to continuously vary the transducer thickness or effectiveness, or alternatively to optimize the effective area of a constant thickness transducer. The variation in the thickness may be optimized using the underlying finite element model shape functions. The transducers may then be designed using a discrete model, and the thickness recovered via the shape functions. The side constraint of minimizing the curvature of the changes of the transducer shape is introduced to ensure that the resulting shape is as simple as possible. The alternative is to determine the shape of a constant thickness modal transducer. Several approaches will be outlined in the paper. These include using the computed sensor thickness to estimate sensor regions, and the use of a fine finite element mesh to determine which elements should be covered with a transducer. The possibility of using a continuous shape definition will also be explored. The approaches are tested on example plate structures to demonstrate their effectiveness and also to demonstrate the errors introduced for non-proportionally damped structures.
@INPROCEEDINGS{cp12,
AUTHOR={S. Adhikari},
TITLE={Damping modelling and identification using generalized proportional damping},
BOOKTITLE={Proceedings of the 23rd International Modal Analysis Conference (IMAC - XXIII)},
YEAR={2005},
Address={Orlando, Florida, USA},
Month={February},
Organization={Society of Experimental Mechanics (SEM)},
Note={}
}