基于小波理论的双六自由度试验台轨道不平顺模拟

Track irregularity simulation of dual 6-DOF test-bed based on wavelet theory

为了提高轨道不平顺的模拟精度并完善轨道不平顺模拟过程,以轨道不平顺功率谱为研究基础,提出了一种利用小波理论模拟轨道不平顺时域波形的新方法。以美国6级轨道谱为例,分别对比了由三角函数法和小波理论法得到的功率谱模拟值与解析值,明显看出小波理论模拟法精确度更高。将由小波理论模拟法得到的时域波形作为振动激励输入,利用Matlab/Simulink搭建的位姿解算模型进行仿真计算,得到双六自由度试验台各作动器的伸缩量,并在试验台上进行了动态模拟试验,得到的波形复现效果良好,说明本文模拟方法可行。

In order to increase the simulation accuracy and improve the process of track irregularity,with the research foundation of the power spectrum,a new method was proposed by using the wavelet theory to simulate the time domain waveform of track irregularity.Taking the sixth grade track irregularity PSD of US as an example,the simulated values and analytical values of the power spectrum were obtained by using the trigonometric function method and the wavelet theory simulation method respectively.A comparison of the two methods indicates that the wavelet simulation method has higher accuracy.Furthermore,the time domain signal obtained by the wavelet simulation method was taken as the input of vibration excitation,and the extension amount of each actuator of the 2-6 DOF test-bed was obtained by position kinematics solution model,which was built in MatlabSimulink.The simulation experiment was carried out on the test-bed,and good waveform reproduction was obtained,which demonstrates that the proposed simulation method is feasible.