Patent ID: 7895895

Claim:
A method for measuring porosity in a composite material, the method comprising: identifying an attenuation curve and a filter, the attenuation curve formed from a plurality of porosity measurements made from a plurality of panels of the composite material, each of the plurality of panels having a different porosity level, and wherein the filter enables the attenuation curve to be used on a plurality of different ultrasonic measuring systems; emitting a first ultrasonic signal from a transmitting transducer in an ultrasonic measurement system of the plurality of different ultrasonic measuring systems into a material; responsive to emitting the first ultrasonic signal, receiving a second ultrasonic signal at a receiving transducer in the ultrasonic measurement system from the material; filtering the second ultrasonic signal to pass only frequencies in the second ultrasonic signal within a selected frequency range to form a filtered second ultrasonic signal; comparing the filtered second ultrasonic signal to the attenuation curve to form a comparison; and using the comparison to identify the porosity level of the material.