Patent ID: 7383730

Claim:
A method for determining a most representative velocity of a stress wave within a material from a plurality of candidate values, the method comprising the steps of: inducing the stress wave into the material; measuring a first amplitude at a time t 1 ; measuring a second amplitude at a time t 2 caused by travel of the stress wave through the material; measuring a distance traveled by the stress wave within the material in a period of time between the time t 2 and the time t 1 ; determining a first velocity of the stress wave by dividing the distance traveled by the stress wave by the period of time between the time t 2 and the time t 1 ; obtaining resonance measurements of the material after the time t 1 ; subjecting the resonance measurements to a Fast Fourier Transform algorithm to provide the plurality of candidate values; and selecting the most representative velocity from the plurality of candidate values based on a proximity between the first velocity and one of the candidate values.