Measuring and testing – Vibration – Resonance – frequency – or amplitude study
Patent
1989-01-10
1990-05-22
Chapman, John
Measuring and testing
Vibration
Resonance, frequency, or amplitude study
364578, G01N 2904
Patent
active
049266918
ABSTRACT:
A method of determining the stiffness and condition on a wooden structure. The method consists of initiating the natural vibration of the structure in a band of frequencies that cover at least two of the first five resonant modes of vibration. An electrical response equivalent to the vibration motion of the structure is generated and the electrical response is converted to a digital signal. The resonant frequency of the structure is calculated by analysing the digital signal. By comparing the results with the results obtained using a mathematical model the stiffness and condition of the structure is determined.
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Franklin Douglas E.
Murphy Maurice W.
Palylyk Richard A.
Arana Louis M.
Chapman John
Powertech Labs Inc.
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