The invention discloses a sound-wave-based square wood hole-defect
recognition system and a sound-wave-based square wood hole-defect recognition method, which mainly solve the problem of difficulty for nondestructive detection of a hole defect of square wood. The
system comprises a small hammer, a
sound wave signal acquisition module, a
sound wave signal processing module, a NiosII processor, an
external storage module, a
USB (universal serial
bus) communication module and a principal
computer processing module. The
sound wave signal acquisition module is used for completing the sound wave acquisition, AD conversion, amplification and low-
frequency filtering; the sound wave
signal processing module is used for driving the acquisition module and
processing a sound wave
digital signal; the
external storage module comprises an SDRAM (
synchronous dynamic random access memory) and an EPCS (electronic propulsion
control system) configuration memory; the NiosII processor is used for
processing and caching the signal and calling the
USB communication module to upload the data to the principal
computer processing module; a sound wave signal time-domain and frequency-domain waveform characteristic value is extracted from the principal
computer processing module, and the defect is recognized by adopting a
fuzzy model recognition method. The
system and the method are
pollution-free, harmless, simple and convenient to use, high in recognition rate and suitable for detecting the hole defect of the square wood, and the detected wood is not damaged.