The shock loads generated by spacecraft during docking can cause functional failure and structural damage to aerospace electronic equipment and even lead to catastrophic flight accidents.There is currently a lack of s...The shock loads generated by spacecraft during docking can cause functional failure and structural damage to aerospace electronic equipment and even lead to catastrophic flight accidents.There is currently a lack of systematic and comprehensive research on the shock environment of spacecraft electronic equipment due to the diversity and complexity of the shock environment.In this paper,the validity of the finite element model is verified based on the sinusoidal vibration experiment results of the spacecraft reentry capsule.The method of shock dynamic response analysis is used to obtain the shock environment of electronic equipment under different shock loads.The shock response spectrum is used to describe the shock environment of aerospace electronic equipment.The results show that the resonance frequency error between the sinusoidal vibration experiment and the model is less than 4.06%.When the docking relative speed of the reentry capsule is 2 m/s,the shock response spectrum values of one of the equipment are 30 m^(2)/s,0.67 m/s,and 0.059 m,respectively.The wire rope spring on the mating surface can provide vibration isolation and shock resistance.An increase in spring damping coefficient results in a decrease in the amplitude and time of the vibration generated.An increase in spring stiffness reduces the input of shock load within a certain range.These research results can provide guidance for the design and evaluation of shock environmental adaptability of aerospace electronic equipment.展开更多
Aircraft-mounted weapons systems generate intense shock and vibration during combat missions,creating a highly complex,repetitive,and nonstationary environment.Avionic devices and components are susceptible to damage ...Aircraft-mounted weapons systems generate intense shock and vibration during combat missions,creating a highly complex,repetitive,and nonstationary environment.Avionic devices and components are susceptible to damage in severe gunfire shock environments and must undergo shock testing.In the absence of measured data,gunfire shock signals synthesized from Shock Response Spectrum(SRS) should serve as input excitation.However,the synthesis of gunfire shock signals presents several challenges,primarily due to the transient and repetitive nature of gunfire shock itself,as well as the inherent non-linearity in the SRS method.This paper presents a novel method for synthesizing gunfire shock signals that match SRS specifications while maintaining realistic temporal characteristics.The proposed method utilizes a shock-waveform dictionary technique to generate single-shot shock signals with controllable features including initial rise time,effective duration,and repetition intervals.These single-shot signals are then duplicated and concatenated to create multi-shot sequences,with low-frequency compensation applied to meet SRS requirements.The method's effectiveness is demonstrated through a case study simulating the M61A1 aircraft cannon firing at 4 000 rounds per minute,achieving an average error of only 0.35 d B compared to SRS specifications.Further validation across two additional cases with varied single-shot durations and repetition intervals underscores the method's generalizability.The proposed synthesis method provides a practical solution for laboratory testing of avionic equipment under gunfire shock conditions when measured data is unavailable.展开更多
文摘The shock loads generated by spacecraft during docking can cause functional failure and structural damage to aerospace electronic equipment and even lead to catastrophic flight accidents.There is currently a lack of systematic and comprehensive research on the shock environment of spacecraft electronic equipment due to the diversity and complexity of the shock environment.In this paper,the validity of the finite element model is verified based on the sinusoidal vibration experiment results of the spacecraft reentry capsule.The method of shock dynamic response analysis is used to obtain the shock environment of electronic equipment under different shock loads.The shock response spectrum is used to describe the shock environment of aerospace electronic equipment.The results show that the resonance frequency error between the sinusoidal vibration experiment and the model is less than 4.06%.When the docking relative speed of the reentry capsule is 2 m/s,the shock response spectrum values of one of the equipment are 30 m^(2)/s,0.67 m/s,and 0.059 m,respectively.The wire rope spring on the mating surface can provide vibration isolation and shock resistance.An increase in spring damping coefficient results in a decrease in the amplitude and time of the vibration generated.An increase in spring stiffness reduces the input of shock load within a certain range.These research results can provide guidance for the design and evaluation of shock environmental adaptability of aerospace electronic equipment.
基金supported by the National Natural Science Foundation of China(Nos.12302487 and U2241274)the Suzhou Leading Talents Program for Innovation and Entrepreneurship,China(No.ZXL2023160)the Basic Research Program of Taicang,China(No.TC2023JC07)。
文摘Aircraft-mounted weapons systems generate intense shock and vibration during combat missions,creating a highly complex,repetitive,and nonstationary environment.Avionic devices and components are susceptible to damage in severe gunfire shock environments and must undergo shock testing.In the absence of measured data,gunfire shock signals synthesized from Shock Response Spectrum(SRS) should serve as input excitation.However,the synthesis of gunfire shock signals presents several challenges,primarily due to the transient and repetitive nature of gunfire shock itself,as well as the inherent non-linearity in the SRS method.This paper presents a novel method for synthesizing gunfire shock signals that match SRS specifications while maintaining realistic temporal characteristics.The proposed method utilizes a shock-waveform dictionary technique to generate single-shot shock signals with controllable features including initial rise time,effective duration,and repetition intervals.These single-shot signals are then duplicated and concatenated to create multi-shot sequences,with low-frequency compensation applied to meet SRS requirements.The method's effectiveness is demonstrated through a case study simulating the M61A1 aircraft cannon firing at 4 000 rounds per minute,achieving an average error of only 0.35 d B compared to SRS specifications.Further validation across two additional cases with varied single-shot durations and repetition intervals underscores the method's generalizability.The proposed synthesis method provides a practical solution for laboratory testing of avionic equipment under gunfire shock conditions when measured data is unavailable.
