【摘要】 对于参数时变的SDOF系统,提出一种基于多尺度线调频基稀疏信号分解的参数识别方法。该方法能将SDOF系统的强迫振动响应自适应地分解为稳态响应和瞬态响应。从系统的稳态响应可得到外部激振力的频率估计;对系统的瞬态响应用多尺度线调频基稀疏信号分解方法进一步分解,可得到系统的瞬时频率估计,进而可得到系统的刚度和阻尼,从而实现对SDOF系统的参数识别。刚度线性变化、刚度突变与刚度周期缓变3种情况下的参数识别仿真算例表明,本文方法能有效识别线性时变SDOF系统参数,具有重要的工程应用价值。更多还原

【Abstract】 For the SDOF system that has time-varying parameters,a method for structural parameter identification based on multi-scale chirplet sparse signal decomposition(MCSSD) is proposed.In the proposed method,forced vibration response of an SDOF system is decomposed adaptively into steady state response and transient response.From the steady state response,the estimation of the frequency of exciting force can be obtained.By decomposing the transient response using MCSSD,the system’s instantaneous frequency can be obtained and then,the system’s stiffness and damping can be identified.Numerical simulation examples show that the proposed method can indentify the parameters of linear time-varying SDOF systems effectively.更多还原