Random vibration analysis on the support of strapdown inertial navigation system

Vibration of the support is an important factor to the accuracy of strapdown inertial navigation. To get vibration characteristics of the support, FEM model of the support was created with Ansys, and then response characteristics were analyzed on the support under the separated random loads during carrier flight, including the phases of subsonic and subsonic. To validate the analysis method, wide band random vibration test was done on the points of the support, which are used for mounting inertial instruments. The comparison of the analysis and the test data shows that the relative error of analysis result is not more than 13%. According to the two results the support structure was improved. Finally random vibration analysis was carried out on the improved one. The result shows that the acceleration response was largely reduced than before. This research can be a reference of performance improvement of the strapdown inertial support and navigation system precision.