基于精细积分的冲击载荷时域识别方法研究

Impulsive load identification in time domain based on precise time-integration method

假设动载荷在时间步长内为线性函数,结合精细积分法提出了一种新的冲击型动载荷时域识别方法。该方法利用系统响应构造状态空间方程组,进而建立精确的非递推连锁计算格式的时域内动载荷反演模型,它对初值不敏感,无积累误差,计算简单、精确、高效。论文对动载荷识别反问题的不适定性进行了分析,通过正则化技术克服了模型算子的病态特性和响应测量噪音的不利影响。数值仿真算例表明该识别方法在测量数据有噪音污染的情况下,能稳定有效地反演动载荷。

A new impulsive load identification method in time domain was proposed. With this method, the dynamic loads were assumed to be linear functions within a time-step and the precise time-integration method was used. In this new algorithm, a precise load identification model was constructed, it was not based on a recursion- chain computational format, it was not sensitive to initial values and it had no error cumulation. Furthermore, the TSVD regularization technique was used to overcome the influences of ill-conditioned matrix and measuring noise. Numerical examples showed the effectiveness of the proposed algorithm.