Research On Vibration Reduction Technology Of Unmanned Undersea Vehicles Based On Signal Processing Method

Unmanned Undersea Vehicles (UUV) are often consist of a large number of rotating parts, such as bearings and motors. The noise of UUV is mainly caused by mechanical vibration. When vibration of UUV is tested, in order to identify the sources of noise and vibration and improve the characteristics isolation rate of vibration source, the accelerometers are usually installed about each parts, which is too difficult to implement because of the compact mechanical structure and the expense of experiment. Therefore, blind source separation technology is applied to the mechanical vibration signal pretreatment. With fewer Accelerometers only installed on the shell of UUV, an effective separation of the vibration signal causing by the key components is of practical significance.This dissertation researches blind source separation of shell vibration signals measured of UUV prototype stern. This dissertation identifies the source of vibration by the FFT in order to improve the mechanical structure of the prototype, thus reducing the noise of prototype UUV.Experimental data of UUV prototype has been sampled by a self-designed vibration test system in this dissertation, in order to understand the vibration condition of various parts of UUV in various status, and master the modal characteristics of UUV prototype in this dissertation. Vibration signals of measured UUV are analyzed based on blind signal processing and the improvements to the UUV are based on the conclusions of analysis, which tested the effect of blind source separation of UUV vibration signal preliminary, and achieved the goal of reducing vibration and noise. In the study, we found that the size of signal amplitude after the blind signal separation and the size of original signal amplitude of each state keep consistent in the trend.