Research On High Speed Shock Test Method And Shock Response Spectrum

In wartime,naval vessels will inevitably be attacked by enemy weapons such as mines and fish,and the resulting underwater non-contact explosive high-speed shock load will lead to the failure of shipborne equipment and the loss of combat effectiveness and vitality of naval vessels.Therefore,more stringent high-speed shock test should be carried out for shipborne equipment to provide an effective evaluation standard for improving the anti shock performance of shipborne equipment.According to the research status of shock test methods for shipborne equipment,the implementation methods and research progress of high-speed shock test methods in domestic and abroad are analyzed in detail.Firstly,the resonant response high-speed shock test method and the shock amplification high-speed shock test method are analyzed: the resonant response method is adopted to make the shock signal contain the vibration information of the specified frequency,and the calculated shock response spectrum will have a sudden peak at this frequency,and the shock response spectrum value of other frequencies will not be affected.This method can aggravate the shock damage near the natural frequency of the tested equipment and realize the high-speed shock test of the equipment.By setting up the shock amplifier with the drop shock test bed,the peak value of shock acceleration can be increased by more than 10 times,and the high-speed shock test environment can be intensified to meet the requirements of high-speed shock test for shipborne equipment.Then put forward the high-speed shock test method of high-speed shock testing machine with high controllability,good repeatability and wide range of use,which can realize the high-speed shock test of large mass tested equipment,can produce a controllable high-speed shock test environment,the test test of high-speed shock testing machine can achieve up to 10000 g shock acceleration signal.High-speed shock tests are carried out for electromagnetic relays which are indispensable in naval electrical equipment.Firstly,the main failure frequency of electromagnetic relay equipment was tested by vibration sweep frequency at around 1200 Hz.Secondly,the control variable method was used to test the working state and main failure modes of electromagnetic relays with different brands,different rated voltages,different working voltages and different pin numbers when the shock excitation frequency was1200 Hz.The output voltage presented three states: power off,power down and no change under the high-speed shock environment.Finally,the stability of electromagnetic relay equipment with the same parameters was tested by high-speed shock test.When the peak value of the maximum shock acceleration in stable operation was 550 g,the maximum proportion of the total number of tests was 35.5%,and the relays between 540 g to 560 g accounted for 90.3% of the total number of tests,which met the normal distribution.The shock acceleration signal directly measured in high-speed shock test environment contains trend term and other errors.The shock signal is decomposed by wavelet transform,and the best wavelet basis and decomposition scale are determined by pearson correlation coefficient.After the trend term error is removed,the signal is reconstructed and the shock response spectrum is calculated.Compared with the maximum spectrum displacement measured in the test,the maximum deviation between the two is 6.34%,The trend term error is removed.The research results can provide a reference for the high-speed shock test method and high-speed shock damage assessment method of naval equipment,and the research ideas and design methods can be extended to the high-speed shock test in aerospace,aviation and other fields.