An ultrasonic system to measure the strength of wood

Abstract

This project report purposes the design and development of low cost 40kHz ultrasonic system for measuring the strength of the wood. Ultrasonic measurement techniques now a days are advancing exponentially because there is no need to alter the physical or chemical properties of the subject sample. These techniques also provide the internal specification of the sample in the field. In this project through transmission method is used to determine the strength of the wood. To test the proposed technique, wood samples of good wood and biological decayed wood are developed of same volume. Later on the hardware is developed to transmit and receive the acoustic wave as per requirement. The acquired data of the received signal is analysed using MATLAB platform. In which cross-correlation technique is used with earliest peak detection to determine the time of flight of the received signal. Accurate measurement of TOF is later used to determine the modulus of elasticity of the samples in longitudinal direction, which interprets the overall strength of the wood. Number of experiments were conducted in lab environment to avoid noise, temperature and moisture effects. The proposed method successfully completed and an obvious variation in the MOE of samples of good and decayed wood was observed. So it is envisaged that proposed method in this system can be transformed to low cost hand held gadgetry for the large scale wood industry.