Model correction method integrated with frequency, vibration modes and frequency response functions

Abstract

The present invention discloses a model correction method integrated with frequency, vibration modes and frequency response functions. A multi-satellite distributor has complex space configuration characteristics of multiple branches, high center of mass and low frequency, and model correction integrated with frequency, vibration modes and frequency response functions is performed on a established space finite element model. The method specifically comprises the steps of performing preliminary modal analysis on the preliminarily established space finite element model, performing modal and frequency response analysis on the model after primary screening, performing comparison with test results of modal tests and sine sweep tests, performing further correction according to the comparison results, setting the model to be in a flight state, and obtaining a flight state space finite element model. The model can be used for performing dynamic response analysis, or be used for performing full-scale dynamic characteristic and full-scale dynamics response calculation on basic rockets.

Description

technical field [0001] The invention relates to the technical field of spacecraft dynamics analysis, in particular to a model correction method integrating frequency, mode shape and frequency response function, which is used to correct multi-branch complex space structure finite element models. Background technique [0002] The upper stage is located between the rocket and the satellite. In order to adapt to the multi-satellite launch mission, the upper stage distributor is often designed as a complex spatial structure with many branches, high center of mass, and low frequency. At the same time, the effective mass of some branch modes is relatively large. Therefore, it is necessary to establish a fine finite element model to predict the flight response, so as to formulate reasonable test conditions or vibration suppression measures. At the same time, in the ground vibration test of the composite body, in order to avoid over-testing, it is necessary to formulate the interface...

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Problems solved by technology

[0003] The model correction of the upper stage cannot simply copy the carrier rocket or satellite model. The carrier rocket has a relatively large slenderness. Generally, the low-frequency vibration test of the whole rocket is not carried out, but the frequency or mode shape is mainly corrected based on the free boundary mode test. However, this correction The low frequency correction ability of the method is limited, and the upper limit of general frequency correction is not greater than 35Hz

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