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The dynamic behavior of an epicyclic gear train (EGT) with planet gears supported by journal bearing has been analyzed. The nonlinear stiffness of the gear teeth mesh was considered in the dynamic equations. Hydrodynamic bearing analysis on the fluid film between the planet gears and the shafts was executed to calculate the non-linear equivalent stiffness and damping coefficients. Interactive reactions between the gear dynamics and the bearing characteristics has been included. By this analysis, the gear tooth mesh forces at the sun/planet (S/P) and the planet/ring (P/R) gear meshes, the loci of the sun gear as well as planet and ring gear center, and bearing forces on the planet gear shaft have been calculated. Experiments have also been carried out to compare the calculated results using a simple star type planetary gear train. Calculated results have good correlation with experimental values.

In the pressure hose, pressure of fluid is decreasing due to many factors such as friction resistance (f) in inner wall, geometrical resistance factors like circular deformation rate (C.D.R), bending degree, curvature, sectional expansion-contraction ratio and etc.. And the fluid in return hose experiences a high pressure condition within a short time, when sudden impact is delivered on the gear box. At this time, cavities appear in lower static pressure region like inner radius of a bended pipe and hose system at this moment. That happens, because oil pressure remains lower than saturated vapor pressure at specific temperature. These cavities cause pressure drop, noise, vibration and damage hydraulic components. Those factors make both performance of vehicle movement and fuel-consumption rate worse. In experiment, pressure drop, vapor pressure and many properties of power steering fluid are measured.

This paper presents a validation method of vehicle suspension models to improve the accuracy of vehicle simulation model and a prediction method of vehicle handling characteristics. Suspension model validation was performed by comparing the simulation results of front and rear suspension model to the suspension quasi-static test results about wheel alignment characteristics like toe, camber, caster, roll steer, lateral force compliance steer and ride rate etc., and the procedure is shown. Suspension test results have been obtained by using suspension parameter measuring machine. For the predictions of handling maneuvers, total vehicle model is built by combining of these validated front and rear suspension models and numerical tire model based on the rig test. Suspension modeling and handling maneuver simulations are performed using general purpose dynamics and kinematics analysis code DADS.

In the forming of TB (Tailored Blank) side outer panel, splits frequently occur in the stretch flange areas. Most splits in these areas are categorized as two different types - one at the end of weldline in blank corner due to the local concentration of deformation on thinner or weaker material resulting from different material gauges or strengths and the other at the die corner due to the lack of draw-in of blank during stamping. Therefore, the proper design of blank shape, weldline placement and drawbead in the stretch flange area is crucial for the successful forming of TB side outer panel. In this paper, the design practice of TB stretch flange forming was investigated. The effects of the selected design parameters such a blank corner radius, weldline position and drawbead restraint forces were examined separately and the optimal TB stretch flange design was examined with respect to the several design parameters.