根据轨/姿控火箭发动机脉冲点火方式下动态推力测试的特点和要求,设计了推力动态测试系统并进行动力学建模,采用模态分析理论研究系统的动态性能,并进行幅频特性与相频特性分析。为该系统在微阻尼条件下测试的不失真提供了理论依据.结合该模型,对测试信号进行傅里叶变换,通过系统幅相频特性与不同频率信号进行代数运算的方法,求得了测试系统动态测试误差,从理论上证明测试系统动态性能满足设计要求.
According to the characteristics and demands of dynamic thrust measurement for orbit/attitude control rocket engine, the dynamic thrust measurement system is researched and designed. The dynamic model is discussed and the dynamic ability is investigated through mode analysis theoretics, then its mathematic model and transfer function are set up, which are proved reliable by experiments. The dynamic transfer characteristic is analyzed and it is proved that the system is authentic with potty damp. Combining the model, the testing signal is changed into Fourier progression, then the dynamic testing errors are obtained when the system dynamic ability and different frequency signals progress in algebra. It is shown that the system dynamic ability satisfies the design requirements.