压电式推力测量装置模态参数辨识研究

Study on identification of modal parameters of piezoelectric thrust measuring device

以实验室研制的压电式推力偏心量装置为研究对象,通过锤击法获取了测量装置的特性曲线,基于非线性模态分析方法,编制了模态参数辨识程序,得到了测量装置三个方向的理论动态响应传递函数。辨识得到的理论传递函数伯德图与实测相比吻合,验证了所得到的理论传递函数的正确性。利用传递函数,进一步得到各阶固有频率与测量装置各环节的关系,为找到装置的薄弱环节并提高其固有频率提供有力依据。

Piezoelectric thrust eccentricity measurement device is developed in the laboratory as the research object. The characteristic curves of the measuring device are obtained by hammering. Based on nonlinear modal analysis method,modal parameter identification program is worked out,and the theoretical dynamic response transfer functions in three directions of the measuring device are obtained. The identified theoretical transfer function Bode diagram is in good agreement with the amplitude and phase frequency characteristic curves obtained experimentally,and the correctness of the theoretical transfer function is verified. By using the transfer function,can be obtained relationship between the natural frequencies of each order and each link of the measuring device,and provide a strong basis for finding the weak links and improving the natural frequencies of the devices.