• Title/Summary/Keyword: 언더스티어

Search Result 4, Processing Time 0.015 seconds

Stochastic Analysis for Vehicle Dynamics using the Monte-Carlo Simulation (Monte-Carlo 시뮬레이션을 이용한 확률적 차량동역학 해석)

  • Tak, Tae-Oh;Joo, Jae-hoon
    • Journal of Industrial Technology
    • /
    • v.22 no.B
    • /
    • pp.3-12
    • /
    • 2002
  • Monte-Carlo simulation technique has advantages over deterministic simulation in various engineering analysis since Monte-Carlo simulation can take into consideration of scattering of various design variables, which is inherent characteristics of physical world. In this work, Monte-Carlo simulation of steady-state cornering behavior of a truck with design variables like hard points and busing stiffness. The purpose of the simulation is to improve understeer gradient of the truck, which exhibits a small amount of instability when the lateral acceleration is about 0.4g. Through correlation analysis, design variables that have high impacts on the cornering behavior were selected, and significant performance improvement has been achieved by appropriately changing the high impact design variables.

  • PDF

A Study on the Effects of Suspension Design Parameters on Cornering Performances of a Vehicle (차량의 선회성능에 미치는 현가장치 설계인자의 영향에 관한 연구)

  • 이장무;윤중락;강주석;정종혁;탁태오
    • Transactions of the Korean Society of Automotive Engineers
    • /
    • v.4 no.4
    • /
    • pp.27-37
    • /
    • 1996
  • In this paper the effects of suspension design parameters on the steady-state cornering performance of vehicles are studied. To investigate the understeer characteristics of vehicles, steady-state cornering equatons are derived from a two-track model which is expanded from a simple one track model. The effects of the suspension design parameters as well as those of lateral load transfer are taken into consideration. To verify the equation, a skid pad test was carried out with a domestic passenger car. The design parameters of the vehicle are measured using a Suspension Parameter Measuring Device(SPMD). Based on these results, parameter studies are carried out to determine the effect of design parameters on the cornering performance of a vehicle, both in low and high acceleration region.

  • PDF

A Study on the Steady-State Cornering of a Vehicle Considering Roll Motion (롤 운동을 고려한 차량의 정상상태 선회주행에 관한 연구)

  • 이장무;윤중락;강주석;배상우;탁태오
    • Transactions of the Korean Society of Automotive Engineers
    • /
    • v.5 no.6
    • /
    • pp.89-102
    • /
    • 1997
  • In this study, the steady state cornering behavior of a vehicle is investigated by using a numerical model that has parameters associated with roll motion. The nonlinear characteristics of tire cornering forces and aligning torques are presented in analytical forms using the magic formula. The sets of nonlinear algebraic equations that govern the cornering motion are solved by the Newton-Raphson iteration method. The vehicle design parameters are measured by SPMD(Suspension Parameter Measuring Device), and its results are verified by carrying out a skid pad test. The design parameters that are most affecting the steady state cornering behavior are classified into four factors, and the contributions of the factors to understeer gradient are then calculated.

  • PDF

A Study on the Handling Performances of a Large-Sized Bus with the Change of Rear Suspension Geometry (후륜 현가장치 지오메트리 변화에 따른 대형 버스의 조종 안정성 연구)

  • 서권희;국종영;천인범
    • Transactions of the Korean Society of Automotive Engineers
    • /
    • v.9 no.4
    • /
    • pp.176-183
    • /
    • 2001
  • It is difficult to find out the kinematic characteristics of a vehicle suspension without the usage of CAE software. The application of CAE software into suspension kinematics and dynamics yields the more precise knowledge on the chassis design. In this study, the influence of the suspension geometry on the handling performances of a large-sized bus is investigated using the DADS software. The front and rear suspension of a large-sized bus are a rigid axle suspension with the four control links. The elastokinematic analysis is performed to evaluate the roll characteristics of the front and rear suspension. The elastokinematic responses are evaluated in terms of the roll center height and roll steer for various geometric parameters. The roll center height is mainly dependent on the vertical displacement of a panhard rod and the vertical displacements of lower control links affect the roll steer of a rear suspension. The parameter study with the change of rear suspension geometry is conducted to investigate the vehicle handling performances. This parameter study shows that the vertical displacement and orientation of a panhard rod influence the handling performances of a large-sized bus significantly.

  • PDF