The method using wavelet packet analysis is proposed to extract fault information from vibration signal obtained from testing jig of tilting train . the vector comprised of the energy of signal in all spectrum bands is input to a feed forward neural network 利用小波包分析,将摆式车体试验台上采集到的振动加速度信号分解在相互独立的频带之p内,各频带内的能量值形成一个向量,将其作为神经网络的输入特征向量, 。