基于Houbolt法的动载荷识别方法

利用Houbolt逐步积分和向后差分法，推导出多自由度线性振动系统的响应与系统动力学参数及激励的关系递推表达式，进而提出了一种无条件稳定的动载荷识别方法.以一线弹性悬臂梁为例，利用单频和双频单输入激励、双频双输入激励响应的仿真结果，对其激励载荷进行了识别.将识别载荷的时域误差和频谱成分与传统的状态空间法识别结果进行了对比，验证了本载荷识别方法的时域和频域相对误差均更小，且无增频现象，提高了识别精度，且具有良好的抗噪性.

Dynamic Load Identification Based on the Houbolt Method

The formulae of the dynamic response related to the excitation and dynamic parameters for a multiple-degree-of-freedom linear vibration system were deduced by virtue of the Houbolt integration and backward difference methods. Then a new method for load identification of unconditional stability was proposed. Taking a linear elastic cantilever beam as an example， the exciting loads were identified using the simulation results of the single inputs of single frequency and dual frequencies， and the dual inputs of dual frequencies. Compared with the conventional state space method， the relative errors and frequency spectrum of the loads identified by the proposed method were smaller in both time and frequency domains， and there was no frequency increasing. This proposed method has improved identification accuracy and has a good anti-noise performance.