Active front steering(AFS) system is able not only to vary steering ratio between steering wheel and tire wheel but also to steer front tires independently. In this paper, steering gear ratios and an active steering algorithm are proposed for the AFS system. Steering gear ratio is a function of vehicle speed and steering angle. Active steering is generated when the error of yaw-rate is larger than some threshold. To verify the performance of yaw stability, hardware-in-the-loop simulation system is made up of column type active steering system, driving display, steering effort reaction system and controller

Steering gear is the part of an automobile that change circular movement of steering wheel to lateral movement of rack to change driving direction. This can be classified with manual and power steering gear. Manual steering gear is operated only with human power while power steering gear use oil pressure support. These days power steering gear is more common to almost of the car. Recently a korean company manufactures a speed sensitive power steering which provide variable steering feel depend on the speed of car. The Broens company of Australia produces and exports the test equipments for the manufacture of power steering valves and assemblies to major vehicle manufactures. Some korean companies imported the test equipments from Australia, thus increasing the cost. The purpose of this study is development of the valve balance test equipment to measure the valve torque of the power steering gear. This study designed and manufactured the valve balance test equipment to take hold of the power steering valve using CAE analysis. In order to evaluate the performance of the developed valve balance test equipment, the R&R tests have been conducted.

Reduction of ship's rolling is the most important performance requirement for improving the safety of the crew on board and preventing damage to cargo as well as improving the comfort of the ride. It is a common experience for mariners, to see that steering with a rudder generally induces rolling of the ship, though the original aim of the rudder is to keep the ship's heading to the required course. At the first stage, when a rudder is steered, usually a ship heels in an inward direction, due to the roll moment acting on the rudder. At the next stage in steering, the main heel may change to an outward. This coupling between rudder and roll motion has become an attractive problem from the point of view of roll stabilization using the rudder, because it is a natural in sight that if the rudder action is skillfully related to the change of roll as well as to the course deviation, the roll can be reduced to a certain degree. The main aim of this paper is to discuss the results of the actual full-scale sea trials carried out on steer gear No.1 and No.1 2, the individual quartermaster and to make clear their statistical properties, using the actual data which included measurement of roll angle, roll rate and the comparative tests were carried out immediately after each other, in order to minimize any statistical variation in sea conditions. It can be concluded that the steer gear No. 1 2 reduced the roll motion on average by about 21% in comparison with the No.1 and confirmed the some difference as per a ability of quarter-master's maneuver.

Generally, the three position solenoid valve has veen used for the hydraulic steering gear on account of it’s low cost, simplicity in device, etc. But, there is some off-set because of dead-zone which exists in on-off valves. In this paper, we proposed a combined controller which was added an integral controller to an only on-off one in hydraulic steering gear control system used low speed three position solenoid valve. Experimental results show that the off-set is removed, and the number of valve switching is reduced considerable. The validity of proposed method comparing with an only on-off control was proved by the response experiments.