开环虚拟振动试验方法在航天遥感器上的应用研究

Application of Open-loop Virtual Vibration Test Method on the Space Remote Sensor

振动环境试验是产品研发过程的重要试验项目,虚拟振动试验已成为一种减少试验、降低成本的高效解决方案。文章基于开环虚拟振动试验方法,对某遥感器进行频域开环和时域开环虚拟振动试验研究和仿真。仿真结果与试验数据的对比表明,频域开环和时域开环都很好的复现了振动试验过程,尤其是在低频段的试验结果。对于时域开环中激励信号的处理,文章创新性采用了时域波形再现(TWR)技术,基于台面加速度控制谱迭代反算位移激励信号的方法,有效的解决了非约束机械系统直接施加加速度或力激励漂移的问题。将仿真得到的响应结果与台面加速度控制谱进行了对比分析,验证了在一定范围内该方法的可行性。文章最后研究了偏载效应,拓宽了时域开环虚拟振动试验方法的应用范畴。文章结果有利于虚拟环境试验的推广,缩短研制时间。

The vibration environment test is an important test item in the product research and development process. Virtual vibration test has become an efficient solution to reduce the test and cost. Based on the open-loop virtual vibration test method, the vitual vibration tests in frequency and time domains for a remote sensor are simulated and studied in this paper. By comparing the simulation results with the experimental data, the open-loop virtual test can reproduce the vibration test process very well, especially in the low frequency band, which is in good agreement with the experimental results. Because the finite element model of the specimen has not been updated by the test data, the simulation and test curves do not coincide so well as in the low frequency band. For the time domain open-loop virtual vibration test method, the influence of non-linear factors such as contact, collision, friction, coupling between fixture and specimen etc, and the coupling with the excitation system could be further considered. For the excitation signal of the time-domain open-loop virtual vibration method, an innovative technology named TWR (Time Wave Replication) technology was adopted to iteratively calculate the displacement excitation signal from the known acceleration signal, which effectively solves the non-convergence problem when directly applying acceleration or force excitation to the unconstrained mechanical systems. At the same time, by comparing the simulation results with the acceleration control spectrum of the platform, the feasibility of the proposed method is verified in a certain range. Finally, the bias effect is studied, which broadens the application scope of time domain open-loop virtual vibration test method. The results of this paper are beneficial to the popularization of virtual environment test and shorten the development time.