Extraction of natural frequencies and vibration modes of a sample of single-rail sled tester system with dampers

In this paper, the vibrations on the sample of a single-rail sled tester system with dampers are investigated. First, by extracting the vibration equations governing the problem coded in MATLAB software and by drawing the FFT diagram, the natural frequencies of the system are obtained. The first and second frequencies of the system are related to torsional displacement and transverse sled displacement, respectively. Due to the structural damping of the sled system, to extract the equivalent stiffness and equivalent damping values, the experimental test is used by the harmonic dynamic test device. Then, by simulating the sled model in ABAQUS software, modal analysis is performed and natural frequencies and mode shapes are extracted. Finally, by constructing a designed sled model and performing experimental modal analysis, the natural frequencies of the system are compared with the previous two methods and confirmed with an error of less than 9%.KeywordsSled tester system, natural frequency, modal analysis, equivalent stiffness, equivalent damping.