Prototype Development And Experimental Analysis Of Viscoelastic Damping Truss Vibration Isolator

In the rocket launch and blastoff process, satellites should withstand the loadchanging over time which is caused by environmental changes, such as overload,vibration, shock and noise. These effects of those environmental loads would provoke agreat destructive influence to the spacecraft, if the response is too large, the structurewill lead to the destruction of local instability or failure of electronic components, etc.,as well as damage to the instrument and structural fatigue damage.Therefore，thevibration isolation technology to whole spacecraft is developed that vibration isolatorsare used to replace the current widespread use of rigid adapters to isolate vibration loadson the satellite that transmitted by the rocket and improve the dynamic environment ofthe satellite.Based on the principle of the whole spacecraft isolation techniques and the existingdomestic and international isolation technology status, a kind of constrained viscoelasticdamping truss isolator is developed to replace the original rigid adapter installedbetween the satellite and rocket as a supporter and bring vibration isolation to the wholespacecraft at the same time. Software PRO/E is applied for three dimensional modelingof the vibration isolation, two different types of which that with and without dampingrod is designed for comparison. Besides, dynamic equations of the system areestablished between rigid isolators and satellites that natural frequencies and modeshape of the isolator without damping rod and rigid satellite system are obtained bycalculating and the parameter of the circumferential angle on the isolator is optimized.Further, vibration characteristics of these two systems are obtained by forced vibrationanalysis in ADAMS respectively. Modal analysis of the base and the isolator withdamping rod as well as harmonic response analysis of the three-dimensional model aretaken in finite element simulation software ANSYS Workbench, from whichacceleration response curve of the vibration isolator under load and displacement mapof the system near the peak of the transfer rate are received.Vibration tests of the prototype are conducted in the final part, which contain thetest of vibration transmissibility from the bottom to the top and tests of four systems atboth horizontal and vertical vibration that assembled by two different isolatorsmentioned before and two kind of satellite-the rigid and flexible one, respectively. Theresults not only confirmed that the low-frequency vibration load from the bottom of theisolator can be effectively isolated but also shows that the experimental results and thetheoretical calculations agree well with the simulation results in the software. Thetheoretical model, software simulation and experiment of the text can be used for theactual design of passive isolator for the whole satellite.