4축 유압 시뮬레이터의 진동특성에 관한 연구

Abstract

The frequency analysis means analysis and interpretation of the own characteristic of the some objects using conversion from time dimension signal to frequency dimension signal. In frequency dimension, one of the analyzed signals sharply changes at special frequency and phase. That frequency is called the eigenfrequency or natural frequency and regarded as the characteristic of the hydraulic simulator. The natural frequency is an important factor when the mechanisms are designed because the special phenomenons(noise, vibration, failure, etc), the influence of the fatigue life of components, occur in natural frequency. So, to understand the vibration characteristics of 4-axis hydraulic simulator is the most important point to increase the reliability of the hydraulic simulator. In this thesis, measurement program for the impact experiment and simultaneous input-output measurement program are developed for understanding the vibration characteristics of 4-axis hydraulic simulator. Programs are designed to enable user to measure and analyze the data in various situation and to easily change the variables, for example, the type of input signals, window function, averaging mode, etc. In the impact experiment, the impact signals made by the impact hammer at the various positions are acquired through the three accelerometers and the natural frequency is analyzed by the measurement program for the impact experiment. In the random signal experiment, the hydraulic simulator's piston is driven by the random signal using the simultaneous input-output measurement program. Acquired data about the hydraulic simulator are analyzed by simultaneous input-output measurement program to get the hydraulic simulator's natural frequency. Used random signals are Gaussian white random signal, periodic white random signal and uniform white random signal. Acquired data about the hydraulic simulator's frequency analysis are compared with preceded experiment data about the 4-axis hydraulic load simulator. This comparison will be expected to support the reliability about road profile realization of 4-axis hydraulic simulator.