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This paper proposes a torque tracking algorithm via steer by wire to achieve the target steering feel and proposed a modified friction model to obtain return-ability. A three dimensional reference steering wheel torque map is designed using the measurement data of the steering characteristics of the target vehicle at a transition test and a weave test. In order to track the reference steering wheel torque, a sliding mode control is used in the tracking algorithm. In addition, to achieve return-ability, the modified friction model for steer by wire is used instead of the friction model defined in the reference steering wheel torque map. The modified friction model is composed of various models according to the angular velocity. The angular velocity and the angular acceleration used in the control algorithm are estimated using a kalman filter.

This paper proposes a reference steering wheel torque map and a torque tracking algorithm via steer-by-wire to achieve the targeted steering feel. The reference steering wheel torque map is designed using the measurement data of rack force and steering characteristic of a target performance of the vehicle at transition steering test. Since the target performance of the vehicle is only tested in nominal road condition, various road conditions such as disturbances and tire-road friction are not considered. Hence, the measurement data of the rack force that reflects the road conditions in the reference steering wheel torque map have been used. The rack force is the net force which consists of tire aligning moment, road friction force and normal force on the tire kingpin axis. A motor and a magnetorheological damper are used as actuators to generate the desired steering feel using the torque tracking algorithm.

As an effective approach for the design, implementation and test of control systems, hardware-in-the-loop (HIL) test has been used in many research areas. This paper describes a real-time HIL simulation test for an automotive electronic control system. The HIL system proposed in this paper consists of three parts: real-time target hardware, electronic control unit (ECU) of the automotive electronic control systems and a signal-conditioning unit which regulates the voltage levels between real-time target and ECU. The HIL simulation evaluates mechanical and electronic behaviors in real time using off-line simulation models by interfacing real-target with electrical control units via interface box. The model has been developed by MATLAB/Simulink. The model is composed of mechanical part which predicts dynamic behaviors and electronic part to calculate the motor speeds, current and electronic loads under the various conditions.

The purpose of the present study was to investigate the characteristics of pressure drop, heat transfer rate and drainability for a brazed aluminum heat exchanger. Scaled-up models with standard and 30 degree-slant louver fins were made, and their thermal and hydraulic performances were tested in a wind tunnel. The drainability of the fins was compared by measuring the retained water after dipping the heat exchangers. The slant louver fin showed a 13% higher pressure drop and 2% lower heat transfer coefficient than the standard louver fin. It also retained about half of the water that the standard louver fin did.

Electro-Mechanical Brake (EMB) systems can provide improved braking and stability functions such as ABS, EBD, TCS, ESC, BA, ACC, etc. For the implementation of the EMB systems, reliable and robust fault detection algorithm is required. In this study, a model-based fault detection algorithm is designed based on the analytical redundancy method in order to monitor possible faults in EMB systems. The performance of the proposed model-based fault detection algorithm is verified in simulations. The effectiveness of the proposed algorithm is demonstrated in various faulty cases.

The control logic of electronically controlled hydraulic brake system for hybrid vehicle is introduced in this paper. The hybrid brake system consists of the electronically controlled hydraulic brake system, electric motor and vacuum management system. The electronically controlled hydraulic brake system is developed and named as Advanced ESC system. This system has 14 linear valves, a motor, and multi-pumps. These linear valves are tested to find the dynamic characteristics, which is the relation between hydraulic force, magnetic force and spring force. By using this force relation, valve is controlled to be open or closed state. The multi-pumps are adapted to improve NVH and hydraulic pressure rise rates. After the regenerative brake torque of electric motor is studied, the control flow chart of this brake system is determined. During vehicle stop, the regenerative brake torque of electric motor gradually increases and then reaches to max torque to regenerate.

This paper describes the MANDO MGH ESP (Electronic Stability Program) and consists of the control philosophy, hydraulic actuator and the simulation and test results. The ESP system controls the dynamic vehicle motion in the emergency situation such as the final oversteer and understeer and allows the vehicle to follow the course as desired by the driver. The MANDO MGH ESP is integrated with the existing MANDO MGH ABS/TCS, which is improved with the more information and controls both brake pressure and engine torque for the optimal performance. The look-up tables are emphasized to have the accurate target yaw rate of the vehicle and obtained from vehicle test for the whole operation range of the steering wheel angle and vehicle speed. The wheel slip control is applied for the yaw compensation and the target wheel slip is determined by error between the target yaw rate and actual yaw rate.

This paper investigated the characteristics of the magnetic field and the attractive magnetic force in a magnetic clutch of the automotive air conditioner. The magnetic force was calculated by using the finite element method, the principle of virtual work and the Maxwell stress tensor, and it was measured by experiment. Magnetic field is not affected by the pulley groove and the attractive magnetic force is also not significantly affected by the bearing because the total magnetic field in the airgap is not changed. The magnetic force increases rapidly as the airgap decreases. The bridges in the disk and the pulley decrease the magnetic force because they create the radial flux to saturation and reduce the effective axial magnetic flux in the airgap to the amount of the radial magnetic flux flowing in the bridges. Also the magnetic force is decreased proportionally as the increase of the cross-sectional area of bridge.