• Transactions of the Korean Society of Automotive Engineers
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• v.18 no.2
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• pp.67-73
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• 2010

In this study, a camber angle generating mechanism for rear suspension is suggested. An experimental device is implemented and tested. A full vehicle model with camber angle generating device by using ADAMS/Car is modeled. Rear left wheel and rear right wheel have 5 different camber angles in the simulations, respectively. Step steer and pulse steer simulations are carried out for investigating the effects of vehicle handling performance due to camber angle control of rear suspension. According to the results, the camber angle of rear suspension affects the vehicle handling performance during both simulations. Therefore, when the vehicle makes the right turn or left turn, left and right wheel should have the proper orientation for improving the handling performance, respectively.

• Transactions of the Korean Society of Automotive Engineers
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• v.19 no.6
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• pp.23-29
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• 2011

In this study, a camber angle generating mechanism for front and rear suspension is suggested. An experimental device is implemented and tested. A full vehicle model with camber angle generating device by using ADAMS/Car is modeled. Step steer simulations are carried out for investigating the effects of vehicle handling performance due to camber angle change of front and rear wheel. According to results, the camber angle of rear suspension affects the vehicle handling performance during both simulations. Therefore, when the vehicle makes the right turn or left turn, left and right wheel of front and rear suspension should have the proper orientation for improving the handling performance, respectively.

• Advances in Automotive Engineering
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• v.1 no.1
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• pp.1-20
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• 2018

The aim of this study is the optimization of the parameters of interconnected Hydro-Pneumatic (HP) suspension system of a three-axle vehicle for ride comfort and handling. For HP suspension systems of equivalent vertical stiffness and damping characteristics, interconnected HP suspension systems increase roll and pitch stiffness and damping characteristics of the vehicle as compared to unconnected HP suspension systems. Thus, they result in improved handling and braking/acceleration performances of the vehicle. However, increased roll and pitch stiffness and damping characteristics also increase roll and pitch accelerations, which in turn result in degraded ride comfort performance. Therefore, in order to improve both ride comfort and vehicle handling performances simultaneously, an optimum parameter set of an interconnected HP suspension system is obtained through an optimization procedure. The objective function is formed as the sum of the weighted vertical accelerations according to ISO 2631. The roll angle, one of the important measures of vehicle handling and driving safety, is imposed as a constraint in the optimization study. Upper and lower parameter bounds are used in the optimization in order to get a physically realizable parameter set. Optimization procedure is implemented for a three-axle vehicle with unconnected and interconnected suspension systems separately. Optimization results show that interconnected HP suspension system results in improvements in both ride comfort and vehicle handling performance, as compared to the unconnected suspension system. As a result, interconnected HP suspension systems present a solution to the conflict between ride comfort and vehicle handling which is present in unconnected suspension systems.

• Transactions of the Korean Society of Automotive Engineers
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• v.8 no.4
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• pp.130-140
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• 2000

In this paper the reference model following control(RMFC) scheme through the optimal control theory is investigated for the independent rear wheel steering(IRWS) vehicle. RMFC vehicle follows the dynamic performance of a virtual vehicle as a reference model deisgned in the controller. Linear vehicle model of two degres-of-freedom is used to derive control scheme which is applied to full vehicle for evaluating handling performances. And 4WS vehicle through RMFC is compared to the conventional 2WS vehicle and 4WS vehicle in the J-turn test. The RMFC logic is also extended to IRWS vehicle, IRWS with RMFC shows not only the excellent handling performance but salso some advantages in terms of the directional stability and responsiveness from the simulation results.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.15 no.7 s.100
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• pp.799-805
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• 2005

This paper describes the development process of high stiffness body for ride and handling performance. High stiffness and light weight vehicle is a major target in the refinement of Passenger cars to meet customers' contradictable requirements between ride and handling performance and fuel economy This paper describes the analysis approach process for high stiffness body through the data level of body stiffness. According to the frequency band. we can suggest the design guideline about lg cornering static stiffness, torsional and lateral stiffness, body attachment stiffness. The ride and handling characteristic of a vehicle Is significantly affected by vibration transferred to the body through the chassis mounting points from front and rear suspension. It is known that body attachment stiffness is an important factor of ride and handling performance improvement. And high stiffness helps to improve the flexibility of bushing rate tuning between handling and road noise. It makes possible to design the good handling performance vehicle and save vehicles to be used in tests by using mother car at initial design stage. These improvements can lead to shortening the time needed to develop better vehicles.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2004.11a
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• pp.358-361
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• 2004

This paper describes the development process of high stiffness body for ride and handling performance. High stiffness and light weight vehicle is a major target in the refinement of passenger cars to meet customers' contradictable requirements between ride and handling performance and fuel economy. This paper describes the analysis approach process for high stiffness body through the data level of body stiffness. According to the frequency band, we can suggest the design guideline about Is cornering static stiffness, torsional and lateral stiffness, body attachment stiffness. The ride and handling characteristic of a vehicle is significantly affected by vibration transferred to the body through the chassis mounting points from front and rear suspension. It is known that body attachment stiffness is an important factor of ride and handling performance improvement. And high stiffness helps to improve the flexibility of bushing rate tuning between Handling and road noise. It makes it possible to design the good handling performance vehicle at initial design stage and save vehicles to be used in tests by using mother car at initial design stage. These improvements can lead to shortening the time needed to develop better vehicles.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.37 no.7
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• pp.937-943
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• 2013

An independently driven electric corner module cannot be applied to an actual vehicle without some difficulty, because of vehicle safety problems in the case of malfunctions and degraded ride and handling performance owing to the increase in the unsprung mass. In this study, a simulator is developed to evaluate the vehicle driving performance in order to solve ride and handling problems. Component modeling of a small-sized electric vehicle with an independently driven electric corner module is performed using MATLAB/Simulink. The vehicle is modeled by using CarSim, which can be used to analyze the vehicle maneuvers with 27 DOFs. The control algorithm for the improvement of vehicle driving safety and ride and handling performance is validated by using the developed simulator.

• International Journal of Automotive Technology
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• v.6 no.1
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• pp.29-35
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• 2005

The structural integrity of either a passenger car or a light truck is one of the basic requirements for a full vehicle engineering and development program. The results of the vehicle product performance are measured in terms of ride and handling, durability, Noise/Vibration/Harshness (NVH), crashworthiness, and occupant safety. The level of performance of a vehicle directly affects the marketability, profitability and, most importantly, the future of the automobile manufacturer. In this study, the Virtual Proving Ground (VPG) approach has been developed to simulate dynamic nonlinear events as applied to automotive ride & handling. The finite element analysis technique provides a unique method to create and analyze vehicle system models, capable of including vehicle suspensions, powertrains, and body structures in a single simulation. Through the development of this methodology, event-based simulations of vehicle performance over a given three-dimensional road surface can be performed. To verify the predicted dynamic results, a single lane change test was performed. The predicted results were compared with the experimental test results, and the feasibility of the integrated CAE analysis methodology was verified.

• Korean Journal of Computational Design and Engineering
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• v.3 no.1
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• pp.40-47
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• 1998

Recently, the various driving simulator have been used widely to analyze the handling performance of vehicle and to verify the motion control algorithm of vehicle. In this study, a virtual driving simulator based on the 20-DOF vehicle model is realized to estimate the handling performance and stability of a 4WS (Four-wheel-steering) and/or 4n(Four-wheel-driving) vehicle. Especially the DC motor controlled 4WS actuator is modelled in order to reflect the effect of the responsiveness of actuator on the handling performance and stability. And the realized simulator can be applied to develope a real time simulation system for designing and testing the real vehicles.

• International Journal of Automotive Technology
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• v.8 no.5
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• pp.629-636
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• 2007

This paper describes the process of analyzing vehicle stiffness in terms of frequency band in order to improve vehicle handling. Vehicle handling and ride comfort are highly related to the systems such as suspension, seat, steering, and the car body design. In existing analytical processes, the resonance frequency of a car body is designed to be greater than 25 Hz in order to increase the stiffness of the body against idle vibration. This paper introduces a method for using a band with a frequency lower than 20 Hz to analyze how stiffness affects vehicle handling. Accordingly, static stiffness analysis of a 1g cornering force was conducted to minimize the deformation of vehicle components derived from a load on parts attached to the suspension. In addition, this technology is capable of achieving better performance than older technology. Analysis of how body attachment stiffness affects the dynamic stiffness of a bushing in the attachment parts of the suspension is expected to lead to improvements with respect to vehicle handling and road noise. The process of developing a car body with a high degree of stiffness, which was accomplished in the preliminary stage of this study, confirms the possibility of improving the stability performance and of designing a lightweight prototype car. These improvements can reduce the time needed to develop better vehicles.