This work aims to improve the setup of an electrodynamic triaxial shaker prototype with respect to its usability for the automotive industry.Triaxial shakers being capable of meeting the corresponding requirements are...This work aims to improve the setup of an electrodynamic triaxial shaker prototype with respect to its usability for the automotive industry.Triaxial shakers being capable of meeting the corresponding requirements are not available as standard test equipment.Modifications on the fixture have to be conducted in order to ensure an effective control.The first part of the work is the qualitative description of the system behavior.Therefore,the shaker is treated as a black box.The second part is the modification of the test fixture in order to handle the resonances of the shaker,which is elementary for its usage.A setup is found,that improves testing within the desired frequency range.Thereby,acceleration levels are considered as well as excitation phases and coherences.The proposed setup is used for an exemplary specimen with two different control scenarios.Conclusions are then drawn about the usage of triaxial shakers.展开更多
The purpose of the vibration test of spacecrafts is to assess their adaptability to low-frequency vibration environment during lift-off.This paper gives the simulation of the satellite ground vibration test(GVT) and t...The purpose of the vibration test of spacecrafts is to assess their adaptability to low-frequency vibration environment during lift-off.This paper gives the simulation of the satellite ground vibration test(GVT) and the state of the satellite along with rocket during lift-off.The simulation results of these two states are compared on condition that the lateral vibration of satellite/launching vehicle(S/LV) interface is the same.It is shown that the dynamic responses of satellite vertex are totally different.This is because there is angular motion of S/LV interface during lift-off,but in the GVT,the angular motion is restrained.By means of numerical simulation of the lift-off state,the angular motion related to the translation motion of S/LV interface can be determined.Then,using this angular motion as supplementary condition to simulate the vibration test,the calculated dynamic responses of satellite vertex are identical with the lift-off state.It demonstrates that supplementing angular motion condition is an effective method to improve spacecraft ground vibration test more identically with the real lift-off environment.Furthermore,it is useful for the application of the multi-degree-of-freedom shaking table,and provides the basis for test condition requirement.展开更多
文摘This work aims to improve the setup of an electrodynamic triaxial shaker prototype with respect to its usability for the automotive industry.Triaxial shakers being capable of meeting the corresponding requirements are not available as standard test equipment.Modifications on the fixture have to be conducted in order to ensure an effective control.The first part of the work is the qualitative description of the system behavior.Therefore,the shaker is treated as a black box.The second part is the modification of the test fixture in order to handle the resonances of the shaker,which is elementary for its usage.A setup is found,that improves testing within the desired frequency range.Thereby,acceleration levels are considered as well as excitation phases and coherences.The proposed setup is used for an exemplary specimen with two different control scenarios.Conclusions are then drawn about the usage of triaxial shakers.
文摘The purpose of the vibration test of spacecrafts is to assess their adaptability to low-frequency vibration environment during lift-off.This paper gives the simulation of the satellite ground vibration test(GVT) and the state of the satellite along with rocket during lift-off.The simulation results of these two states are compared on condition that the lateral vibration of satellite/launching vehicle(S/LV) interface is the same.It is shown that the dynamic responses of satellite vertex are totally different.This is because there is angular motion of S/LV interface during lift-off,but in the GVT,the angular motion is restrained.By means of numerical simulation of the lift-off state,the angular motion related to the translation motion of S/LV interface can be determined.Then,using this angular motion as supplementary condition to simulate the vibration test,the calculated dynamic responses of satellite vertex are identical with the lift-off state.It demonstrates that supplementing angular motion condition is an effective method to improve spacecraft ground vibration test more identically with the real lift-off environment.Furthermore,it is useful for the application of the multi-degree-of-freedom shaking table,and provides the basis for test condition requirement.
