Model-Based Diagnosis for Pre-Stress of Langevin Transducers

The performance of Langevin transducers may be degraded if incorrect mechanical pre-stress is applied. A model-based diagnosis method for the pre-stress of Langevin transducers is studied. An equivalent circuit is used to model the transducer. Based on the measured electrical admittances of transducers for various pre-stress levels, the parameters of the equivalent circuit model were identified by using nonlinear least-square estimation techniques. The model parameter sensitivity with respect to varying pre-stress was analyzed. The result shows the modal damping and admittance maximum have higher sensitivity and are suitable for the diagnosis of transducer pre-stress.