Design And Performance Study Of Multi-dimensional Dynamic Force Application Device

With the aerospace technology gradually moves towards the direction of high precision,the accuracy of spacecraft on-orbit observation is getting higher and higher.When the spacecraft observes the ground,because there are some moving parts inside the spacecraft,it will affect the observation accuracy dues to its own micro vibration.At present,the research on the micro-vibration of the moving parts inside the spacecraft is mainly based on ground testing,and most of the dynamic excitation force sources applied are mainly based on hammer hammering.In order to quantitatively study the problem of dynamic force source loading in the dynamic calibration process of the test device,a multi-dimensional dynamic force application device bases on an exciter is developed to facilitate the study of the dynamic test performance of the test device,and effectively evaluates the impact of the spacecraft's moving parts to add improve.Bases on the background of micro vibration research,this paper proposes two dynamic force source loading schemes to study the dynamic test performance of ground test equipment.The advantages and disadvantages and implementable of the two programs are compared in detail,and a multi-dimensional dynamic force application device bases on an electric vibrator is selected.The theory and simulation analysis of the electric vibration exciter as a force source output element are carried out to verify the feasibility of generating a dynamic force source.Model the application device with Pro / E software,and then imported into ANSYS Workbench for finite element analysis of 3D models,theoretically verify the feasibility and reliability of the application device.In order to detect the magnitude of the output force value of the force source of the applying device,bases on the piezoelectric effect of the quartz crystal,a piezoelectric unidirectional force sensor suitable for dynamic testing is developed.According to the actual working environment of the multi-dimensional dynamic force application device,the dynamic characteristics under this structure form are analyzed,and the second-order system transfer function is constructed according to the finite element analysis results,and then the dynamic force source between the applied force value and the applied frequency is derived the relationship curve.Finally,the effectiveness of the force source of the multi-dimensional dynamic force application device is verified by a dynamic experiment of the test device.The results show that the application device can provide a high-precision dynamic force source,which solves the problem of quantitative force source application in multiple dimensions.The multi-dimensional dynamic force applying device has good dynamic performance and can meet the experimental requirements.Through the relationship curve between the applied force value and the applied frequency,it plays a theoretical guiding role in selecting the actual force source force value and frequency.It provides theoretical guidance for quantitative research on dynamic force source loading in the dynamic calibration process of test equipment.