A method for locating the damage in buoyancy materials of manned submersibles based on polyvinylidene fluoride (PVDF) spherical transducer is proposed to address the problem of difficulty in real-time monitoring and positioning the damaged buoyancy materials during manned submersible operations. A PVDF spherical transducer array based on the optimal quaternion matrix principle was designed to determine the precise location of the damaged buoyancy material in the damaged area. The sound source localization model was established using the time-delay difference method to obtain the exact coordinates of the fracture site of the buoyancy material. To extract effective sound signals from the fracturing of buoyancy materials, a wavelet threshold-based signal denoising method was designed. Based on the localization principle, a software and hardware system for buoyancy material damage location was intended, and the feasibility of the process was verified by constructing an experimental platform. The experimental results show that under a laboratory simulated deep-sea noise environment, the wavelet threshold-based sound signal denoising method can effectively extract the target signal of buoyancy material fracture, and the spherical transducer with the denoised sound signal can accurately locate the damage position.
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