Research On Controllable Six-dimensional Force/Moment Loading For Thrust Vector Measurement Device

The thrust vector test device with piezoelectric dynamometer as its core element has some characteristics,such as high measurement accuracy,good dynamic performance,good stabilityand so on,which has been widely used in dynamic vector force measurement in the fields of aerospace and high-end equipment manufacturing.Thrust vector measurement device is used to evaluate the performance of rocket,so the stability and reliability its measurement performance are very important.Therefore,the performance of measurement device needs to be evaluated.At present,the performance of measurement device is calibrated by static and dynamic calibration methods in an ideal environment.But measurement devices are in the environment which has lots of noises,and the process of installation and debugging can influence its measurement accuracy.Therefore,in this paper,aiming at the thrust vector measurement device,which has good calibration results,working in practical environment,the thought of simulated loading experiments is proposed,and a controllable six-dimensional force/moment loading device is designed,which can realize vector force/moment loading function with three parameters of size,direction and action point being adjustable.And vector force/moment measurement mapping model based on piezoelectric sensors is verified and studied inversely to further evaluate measurement performance of thrust vector test device.Theoretical model of simulation loading system is established.Model I is "top-down" synthesised by multiple space vector force/moment using translation transformation method or spin method,mechanical model of vector force distribution for piezoelectric dynamometer is established,and model II is "down-top" synthesised by 12-channel output components of piezoelectric dynamometer.The research is performed from two aspects,both previous calibration and later simulation loading,which provides theoretical basis for comprehensively evaluating measurement performance of vector force test device.Aiming to the requirements of multi-dimensional force/moment simulation loading,according to loading principle of six-dimensional force/moment,a controllable six-dimensional force/moment loading device,which can which can realize large range ratio vector force/moment loading function with three parameters of size,direction and action point being adjustable,is established.Structural static analysis and modal analysis of key components are performed by Ansys Workbench software.Based on calibrated piezoelectric dynamometer and controllable six-dimensional force/moment loading device,simulation loading experiments of six-dimensional force/moment are performed to verify whether the loading accuracy of controllable six-dimensional force/moment loading device can satisfy loading requirement.Simulation loading system of thrust vector test device is established.Based on the thrust vector test device,one-dimensional simulation loading experiments with loading positions,vector force/moment parameters controllable and two-component forces composite loading simulation experiments are performed,respectively.And vector force/moment measurement mapping relationship model based on piezoelectric sensors is verified and studied inversely to further evaluate measurement performance of thrust vector test device.Through above research,with the way of low cost and easily operating,test system is comprehensively and effectively evaluated by simulated six-dimensional vector force/moment generated by motor before being used ing practical working condition.