• Transactions of the Korean Society of Automotive Engineers
• /
• v.5 no.6
• /
• pp.192-201
• /
• 1997

The feedback control scheme of the pressure control system of the rear wheel steering gear which has relatively large volume and sprung load was built up in order to improve th response characteristic of the system. The control algorithm chosen was a feedback compensator joined by a feedfoward compensator and the model matching method was used in the process of control system design. The structures and properties of the reference models were inspected and the parameters of the controller were decided. The improvement of the response characteristic of the pressure control valve by means of the feedback control is affirmed. Particularly, when the order of the system model is higher than the 2nd order, the effectiveness of the feedback control on the improvement of the response characteristic of the valve is distinct. And the convenience of the model matching method is the process of control system design is confirmed as well.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.4 no.4
• /
• pp.87-96
• /
• 1996

The proportional pressure control valve(PCV) is an essential component in the open loop controlled rear wheel steering gear of the four wheel steering(4WS) system on the passenger car. The valve should have versatile functions and higher performance. But, it is hard to find the proportional pressure control valve suitable for the 4WS system. In this paper, the determination of the valve parameters was studied by the stability discrimination and the characteristic analysis for the purpose of the development of a new PCV for the 4WS. The mathematical model of the valve was derived from the valve-cylinder system and the programme for numerical computation was developed. The transfer function of the system was obtained from the mathematical model. The characteristics of the valve were inspected through the experiment and compared to those obtained by numerical method. And then the stability discrimination of the system was done by root locus and the analysis of characteristics was done by the developed programme. From the experiment and the analysis of characteristics was done by the developed programme. From the experiment and the inspection, the appropriation of mathematical model and the usefulness of the programme were confirmed. And the parameters which might affect the performance of the valve can be determined by considering the stability discrimination, the characteristics analysis and required functions.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.21 no.5
• /
• pp.719-726
• /
• 1997

The proportional pressure control valve having versatile functions and higher performance is an essential conponent in the open loop controlled rear wheel steering gear of the four wheel steering system in a passenger car. In this study, the authors suggest a new type of load pressure feedback mechanism which can make it easy to change the range of controlled pressure without changing the capacity of solenoid. The concept of suggested mechanism, composed of the pressure chamber with throttles in series, was described. The mathematical model was derived from the rear wheel steering gear consisting of a valve and a cylinder for the purpose of analyzing the valve characteristics. And the programme for computing the characteristic of the valve was developed. Experiments were performed to confirm the performance of the valve and computations were carried out to ascertain the usefulness of the developed programme. The results from computations fairly coincide with those from experiments. And the results from experiments and computations show that the performance of new valve was as good as that of the already developed one and the new valve has advantages such as the easiness of changing the range of controlled pressure and the decrease of power loss at neutral position without the decline of performance.

• Proceedings of the Korean Operations and Management Science Society Conference
• /
• 2000.04a
• /
• pp.589-592
• /
• 2000

자동차 man-machine system의 interface를 이루는 Display panel, Center fascia, Steering wheel, Rear view, Gear, Power window switch, Seat 등과 이들의 Layout은 운전자의 안전뿐만 아니라, 안락감과 밀접한 부분으로 알려져 있다. 따라서 이러한 설계요소들의 Man-machine interface의 최적화를 위한 인간공학적 접근이 필요하다. 운전자의 안락감은 Seat, Pedal, Steering wheel 등 뿐만 아니라 각종 조작장치(Audio, Switch, Gear,…)도 함께 연구되어야 하다. 따라서, 본 연구에서는 실험용 Seating buck을 제작하여 실내 조작장치 중 오디오를 대상으로 터치스크린과 Rapid Prototype을 이용해 사용성 평가에 대한 적합성을 검증하고자 하였다. Rapid Prototyping 기법은 디자인단계에서 제품 사용상의 문제점을 발견 개선할 수 있다는 장점이 있다. 그러나, 본 연구 결과에서 3가지 항목 중 1가지만이 실제 Audio와 Prototype에서 차이가 없었다. 따라서, Prototype의 접촉감과 입체감의 개선, 실사용과 동일한 환경의 제시, 소리와 같은 정확한 반응의 제시, Glare의 제거, 사용자 분석에 따른 실험 데이터의 축적 등을 고려하여 Rapid Prototyping을 구현하여야 할 것이다.