Verification of finite-element model spacecraft via test results

The question of ensuring strength, durability and survivability of a spacecraft construction with mathematical mod- eling complexes is a modern trend in satellites design. This approach is based on the shortening of the prelaunch preparation stage. In particular, this is due to the reduction in the number of vibration tests of a spacecraft (SC). In the present work, using the example of vibration tests of “Express-1000K” service system module, we consider the verifica- tion technique for the mathematical model of communication satellites, output by a pair of payloads. The choice of this research object was caused by the conceptual scheme for modern space vehicles constructing, based on the modular principle. The service system module is the basic supporting structure of the spacecraft, able to integrate with any pay- load (information support, scientific research, geodesy and remote sensing, navigation) and is a universal tool in a sat- ellite construction. In tests with harmonic vibration, the first longitudinal and transverse tone of the spacecraft oscilla- tions are well identified, which can be fairly easily predicted applying the finite-element model. Proceeding from this, the accuracy of forecasts depends, to a greater extent, on the complexity of the modeled construction and the modeling procedure being used. The study provides a finite-element modeling technique for spacecraft output by a pair of pay- loads; the dynamic characteristics of the object of investigation by calculation and experimental methods are obtained. The identification procedure was carried out using the ‘modal consent’ method. The verification technique considered in the study makes it possible to carry out effective adjustment of the finite-element model. The finite-element model obtained by verification results allows to effectively evaluate the behavior of a spacecraft already at the design stage, which enables to shorten the time of vibration tests. The main results of this research were applied in verification of mathematical models of modern spacecraft developed by JSC “ISS”. The importance of applying verification methods of the mathematical model of the product at the preliminary (design) stage of spacecraft creation was noted.