A DSP Based Stress Wave Instrument for Wood Decay Detection

To improve the performance of wood decay detection, a DSP based instrument is developed using stress wave technology. Two piezoelectric receivers are used to sense the start and stop signal. The received signals are then processed with DSP technique in order to obtain the stress wave transmission time with high accuracy. In addition to the hardware design, we discuss the propagation time estimation methods. The short-time energy and double threshold detection algorithm are used in this work. Finally, the instrument developed has successfully applied both in a sound tree trunk and a low quality sample which possess a big decay area. The results indicate that the areas of decay can be located and defined precisely using the DSP based stress wave instrument and it is suitable for the application.