Sensor Validation Via Ultrasonic Signal Processing Analysis

The verification of the proper operation of individual sensors is increasingly important as a means of validating the measurements that they generate. One technique for verifying the structural integrity of a transducer and its housing is to use ultrasonic probing, whereby an ultrasonic pulse is generated within the sensor housing. The response signal, which contains multiple resonances, indicative of structural health, is monitored and analyzed. Alternative techniques have been applied to analyze the ultrasonic response signals, obtained from a pressure sensor housing. These include Prism Signal Processing and the Matrix Pencil Method. Both of these techniques are able to track the frequency and amplitude of six or more modes of vibration. Experimental results demonstrate that large shifts in calculated parameter values occur when a fault condition is introduced. In addition, the time varying amplitudes of the modes do not always exhibit the expected exponential decay: this characteristic behaviour may provide an important additional diagnostic information.