• Transactions of the Korean Society of Automotive Engineers
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• v.2 no.5
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• pp.101-109
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• 1994

Recently, four-wheel steering systems have been developed and studied as one of the latest automotive technologies for improving the handling characteristics of a vehicle. In much of the proposed four-wheel steering systems, the side slip angle at the vehicle's center of gravity is maintained at zero. This approach allows the greater maneuverability at low speed by means of counter-phase rear steering and the improved stability at high speed through same-phase rear steering. In this paper, the effects of several four-wheel steering systems are studied and discussed on the responsiveness and stability of the vehicle by using the linear analysis. Especially, the effects of the cornering stiffnesses of both front and rear wheels are investigated on the yaw velocity gain and critical speed of the vehicle.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.2
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• pp.392-397
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• 2006

This paper proposed yaw moment control scheme using braking and active rear wheel steering for improving driving stability especially in high speed driving. Its characteristics the unified chassis control system of two equipment that 4WS(4 Wheel Steering) and ESP(Electronic Stability Program). in this study the performance of the vehicle was compared each equipment. And conventional ABS and TCS can only possible to control the longitudinal movement of braking equipment and drive which can only available to control of longitudinal direction. There after new braking system ESP was developed, which controls both of longitudinal and lateral, with adding of the function of controlling Active Yaw Moment. On this paper, we show about not only designing of improved braking and steering system through establishing of the integrated control system design of 4WS and ESP but also designing of the system contribute to precautious for advanced vehicle stability problem.

• Proceedings of the KIPE Conference
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• 2013.11a
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• pp.69-70
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• 2013

By using differential force between left and right wheel, lateral motion can be controlled known as Direct Yaw-moment Control (DYC). In previous researches, DYC control is proposed to increase the stability of the vehicle, but maneuverability has not been discussed sufficiently. The car handling condition which is called the index parameter of maneuverability is dependent on the vehicle velocity and steering angle. To achieve the desired vehicle's cornering path, the car handling condition must be considered sufficiently. In this paper, the novel DYC method is proposed which gives the car handling condition regardless of the longitudinal speed. The proposed controller is based on the PI controller to feedback the curvature parameter. The controlled system shows the advantages of DYC regarding to the reference trajectory by the dual motor system. With respect to the uncontrolled model, the effectiveness of the proposed method is validated by numerical examples.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.9 no.8
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• pp.1716-1721
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• 2005

Conventionally, 2WS is used for vehicle sleeting, which can only steering front wheel. In case of trying to high speed slalom or emergency through this kind of vehicle equipped 2WS, it may occur much of side slip angle. On the other hand, 4WS makes decreasing of side slip angle, outstandingly, so it is possible to support vehicle movement stable. And conventional ABS and TCS can only possible control the longitudinal movement of braking equipment and drive which can only availab to control of longitudinal direction. There after new braking system ESP was developed, which controls both of longitudinal and lateral, with adding of the function of controlling Active Yaw Moment. On this paper, we show about not only designing of improed braking and steering system through establishing of the integrated control system design of 4WS and ESP but also designing of the system contribute to precautious for advanced vehicle stability problem.