Method and apparatus for assessing or predicting characteristics of wood or other materials by varying frequency of acoustic transmitter and sensing a response

摘要

A method and apparatus for acoustically assessing or predicting a characteristic of a wood specimen to assist in optimising the use of the specimen. The method includes: exciting the specimen with a frequency varying excitation to impart an acoustic wave into the specimen; sensing a response indicative of the acoustic wave behaviour within the specimen; determining a response characteristic of the specimen by signal processing the sensed response; determining at least one resonant frequency of the specimen from the response characteristic; determining an acoustic velocity in the specimen from the at least one resonant frequency; and determining the characteristic using the acoustic velocity. The apparatus includes: a transmitting transducer for coupling to the specimen for generating a frequency varying excitation to impart an acoustic wave in the specimen; a first receiving transducer adapted to sense a response indicative of the behaviour of an imparted acoustic wave; and signal processing means adapted for determining a response characteristic from the sensed response, and for determining at least one resonant frequency of the specimen from the response characteristic. The processing means is further adapted for determining an acoustic velocity in the specimen from the at least one resonant frequency, and for determining the characteristic using the acoustic velocity.