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Axiomatic design is utilized to identify the design characteristics of an On-Line Electric Vehicle and to manage the design information. The On-Line Electric Vehicle, which is being developed at the Korea Advanced Institute of Science and Technology, is a different concept of an electric vehicle from conventional electric vehicles which use the electric power of a charged battery(s). It is operated by an electric power supplied by the contactless power transmission technique between the roadway side and the vehicle. In other words, the power is transmitted based on the principle of an electric transformer. The On-Line Electric Vehicle can overcome the limitations of conventional electric vehicles such as the weight of the battery and driving distance problems. Because designers have little experience and knowledge about the On-Line Electric Vehicle in the developmental stage, an appropriate design guide is needed. The axiomatic approach is employed for the design process.

As world-wide container volume increases and very large container ships emerge as a dominant player in the maritime cargo transport market, functional capabilities of container ports need to be greatly enhanced. To address this problem, KAIST is undertaking a project to design a novel container transport system, namely Mobile Harbor. Mobile Harbor refers to a system that can go out to a large container ship anchoring in the open sea, load and unload containers between the container ship and the Mobile Harbor, and transport them to their destinations. Designing Mobile Harbor presents a number of challenges as with many other large-scale engineering projects, especially at the beginning stage of the project.

A variety of methodologies to use embedded multicore controllers efficiently has been discussed in the last years. Several assumptions are usually made in the automotive domain, such as static assignment of tasks to the cores. This paper shows an approach for efficient task allocation depending on different system modes. An engine management system (EMS) is used as application example, and the performance improvement compared to static allocation is assessed. The paper is structured as follows: First the control algorithms for the EMS will be classified according to operating modes. The classified algorithms will be allocated to the cores, depending on the operating mode. We identify mode transition points, allowing a reliable switch without neglecting timing requirements. As a next step, it will be shown that a load distribution by mode-dependent task allocation would be better balanced than a static task allocation.

The noise of interior plastic parts has been one of the major driving factors in the design of automotive interior assemblies. This phenomenon is one of the major contributors to the perceived quality in a vehicle. The noise is caused by interior plastic parts and other parts as a result of permanent deformation. Traditionally, noise issues have been identified and rectified through extensive hardware testing. However, to reduce the product development cycle and minimize the number of costly hardware builds, hardware testing must rely on engineering analysis and upfront simulation in the design cycle. In this paper, an analytical study to reduce permanent deformation in a cockpit module is presented. The analytical investigation utilizes a novel and practical methodology, which is implemented through the software tools, ABAQUS and iSight, for the identification and minimization of permanent deformation.

In this paper, we propose a vision based lateral control scheme for autonomous lane change system on highways. Three main techniques are proposed, to improve the lane keeping/lane change performance, and to reduce the ripple in the yaw rate on highways. First, we propose a model based lane prediction method to cope with the momentary failure of lane detection. Second, we innovate an approach to steering wheel angle control based on torque overlay for the EPS of the lateral control. Finally, the multi-rate lane-keeping control scheme is proposed to improve the lateral control performance and to reduce the ripple in the yaw rate. The performance of the proposed method was experimentally evaluated via test vehicle

In cold start driving cycles, high viscosity of the lubrication oil (engine oil) increases the mechanical friction losses compared with warmed up condition. Thus, an engine oil warm up system can provide the opportunity to reduce the mechanical friction losses during cold start. In this study, an engine oil heater using EGR is used for the fast warm up of the engine oil. This paper presents the effect of the engine oil heater on the fuel economy and emissions over a driving cycle (NEDC). A numerical model is developed to simulate the thermal response of the powertrain using multi-domain 1-D commercial powertrain simulation software (GT-Suite) and it is calibrated using test data from a full size sedan equipped with a 2.0L diesel engine. The model consists of an engine model, coolant circuit model, oil circuit model, engine cooling model, friction model, and ECU model.

The recent adoption of the ISO26262 Functional Safety Standard has lead to the need for a greater degree of rigor in the technical, organizational and process aspects of electronic ECU engineering. One new facet of this standard also covers (in part 9.7) the analysis of dependent failures at manufacturing time, not only the microcontroller, but also for the plethora of connected system ASICs, input circuits, output drivers and communication devices in the PCB of the ECU. This paper will describe the CAN based end of line ECU self test system that was implemented at a major tier 1 supplier to address the issues of efficiently gaining a high degree of diagnostic coverage of single point faults and latent faults in highly integrated automotive ECUs.

As a new vehicle is based on common vehicle platform, the durability problems of chassis components in development stage are decreasing. However a vehicle body structure is changed by exterior design and a chassis and a suspension are tuned by vehicle performance targets. The main issue on developing a new vehicle is to satisfy the durability target of a body structure and tuned suspension components. The accuracy of durability Computer Aided Engineering analysis is mainly depending on the accuracy of input loads and boundary conditions on suspension system. The input loads should be estimated accurately. These could be changed by vehicle specifications such as vehicle weight, wheel base and so on. It is also affected by the change of suspension types and tuning parameters. This paper presents the experimental parametric study results using road load data analysis techniques.

The series-parallel hybrid electric vehicle(HEV), which employs a planetary gear set to combine one internal combustion engine(ICE) and two electric motors(EMs), can take advantages of both series and parallel hybrid system. The efficient powertrain operating point of the system can be obtained by the instantaneous optimization of equivalent fuel consumption. However, heavy computational requirements and variable constraints of the optimization process make it difficult to build real-time control strategy. To overcome the difficulty, this study suggests the control strategy which divides the optimization process into 2 stages. In the first stage, a target of charge/discharge power is determined based on equivalent fuel consumption, then in the second stage, an engine operating point is determined taking power transfer efficiency into account.

A stoichiometric 2.0L turbocharged DISI engine is developed based upon the Theta 2.0L NA engine. The engine is intended to be installed in a midsize sedan as a downsizing concept, targeting to improve the fuel efficiency of the vehicles installed with the V6 3.3L engines while maintaining the performances. The base 2.0L engine is modified to accommodate the 4∼12MPa direct injection system with the multi-hole injectors and the intake/exhaust variable valve timing (VVT) system. The turbocharger is carefully matched so that the specific power over 85kW/L can be achieved while the maximum torque reached at 2000RPM. The fuel efficiency of the target vehicle was improved significantly due to the reduced friction and pumping losses compared to the vehicle equipped with the V6 3.3L engines. Various advanced gasoline turbocharger technologies for improving the transient performances are evaluated.

For commercial vehicles with a manual transmission, the transfer torque from the clutch pedal to the clutch-cover is very large. Therefore, the pneumatic and fluid pressure servo-device is widely used for transmitting such big torque. However, the pneumatic and fluid pressure servo-devices usually result in non-linear variation of foot-efforts, also variation of foot-efforts have the non-linear character and such non-linear variation tend to increase physical fatigue of drivers who drive commercial vehicles for a long time. To improve the pedal feeling and the design optimally with the clutch disk wear variation, vehicle manufacturers consider the hysteresis loops in the Clutch Actuation System (CAS) design when a new vehicle model is being developed. Generally, the former work to deal with such hysteresis loops were focused on the experimental method and the experimental method is time-consumed and non-cost effective.

In this paper, a nonlinear dynamic engine model is introduced, which is developed to represent an SI engine over a wide range of operating conditions. The model includes intake manifold dynamics, fuel film dynamics, and engine rotational dynamics with transport delays inherent in the four-stroke engine cycles, and can be used for designing engine controllers. The model is validated with engine-dynamometer experimental data. The accuracy of the model is evaluated by the comparison of the simulated and the measured data obtained from a 2.0 L inline four-cylinder engine over wide operating ranges. The test data are obtained from 42 operating conditions of the engine. The speed range is from 1500 (rpm) to 4000 (rpm), and the load range is from 0.4 (bar) to WOT. The results show that the simulation data from the model and the measured data during the engine test are in good agreement.

A new control algorithm of a wedge brake system has been developed. The proposed control algorithm is based on the position control and current control of electronic wedge brake(EWB). The EWB control system in rear wheel has both active braking functions like ABS and ESC and convenient function such as EPB. In this paper, development of control algorithm was performed using hybrid brake system(HBS) which consists of hydraulic brake in front wheel and electronic brake in rear wheel. At first, the configuration of EWB system is explained. Next, structure of electronic control in HBS is explained. And then ABS/ESC/EPB control algorithms are shown. ABS control algorithm has wheel slip calculation, wheel error calculation, wheel slip control, position control, current control, and duty control. ESC algorithm consists of yaw error calculation, yaw moment control, wheel slip control, position control, current control, and duty control.

Mathematical modeling of three-way catalytic converter (3WCC) operation is used increasingly in the optimization of automobile converter systems. But almost all of previous computational models were based on "adiabatic one- channel" approach with the reaction kinetics computations, which is useful and efficient in predicting real-world performance of the catalyst. However, as long as flow maldistribution is not accounted for in the models, simulation results will not be reliable. In this work, two-dimensional performance prediction of catalyst coupled with turbulent reacting flow simulation has been performed and the results were compared with experimental data and one-channel simulation in the literature. The computational results from this study show the better prediction accuracy in terms of CO, HC and NO conversion efficiencies compared to those of 1-D adiabatic model. Varying cell density and hot spot moving pattern within the monolith during warm-up period are also considered.

The purpose of this study was to develop a new element removal method for ESO (Evolutionary Structural Optimization), which is one of the topology optimization methods. ESO starts with the maximum allowable design space and the optimal topology emerges by a process of removal of lowly stressed elements. The element removal ratio of ESO is fixed throughout topology optimization at 1 or 2%. BESO (bidirectional ESO) starts with either the least number of elements connecting the loads to the supports, or an initial design domain that fits within the maximum allowable domain, and the optimal topology evolves by adding or subtracting elements. But the convergence rate of BESO is also very slow. In this paper, a new element removal method for ESO was developed for improvement of the convergence rate. Then it was applied to the same problems as those in papers published previously.

A throttle/brake control law for the intelligent cruise control (ICC) system has been proposed in this paper. The ICC system consists of a vehicle detection sensor, a controller and throttle/brake actuators. For the control of a throttle/brake system, we introduced a solenoid-valve-controlled electronic vacuum booster (EVB) and a step-motor-controlled throttle actuator. Nonlinear computer model for the electronic vacuum booster has been developed and the simulations were performed using a complete nonlinear vehicle model. The proposed control law in this paper consists of an algorithm that generates the desired acceleration/deceleration profile in an ICC situation, a throttle/brake switching logic and a throttle and brake control algorithm based on vehicle dynamics. The control performance has been investigated through computer simulations and experiments.

The present study is mainly motivated to investigate the vaporization, auto-ignition and combustion processes in the high-pressure engine conditions. The high-pressure vaporization model is developed to realistically simulate the spray dynamics and vaporization characteristics in high-pressure and high-temperature environment. The interaction between chemistry and turbulence is treated by employing the Representative Interactive Flamelet (RIF) Model. The detailed chemistry of 114 elementary steps and 44 chemical species is adopted for the n-heptane/air reaction. In order to account for the spatial inhomogeneity of the scalar dissipation rate, the multiple RIFs are introduced. Numerical results indicate that the RIF approach together with the high-pressure vaporization model successfully predicts the ignition delay time and location as well as the essential features of a spray ignition and combustion processes.

Since many electric and electronic systems are continuously added in a vehicle to meet various regulations and customer demands over the last decade, the demand on the electric power have been substantially increased. Furthermore the idle time fraction during the vehicle traveling has been increased due to the heavy urban traffic condition. The electric power system of the modern vehicle has to supply enough electrical energy to numerous electrical and electronic systems. A detailed understanding of the characteristics of the electric power system, electrical load demands, and driving environment such as road, season, and vehicle weight are required when the capacities of generator and battery are determined for a vehicle. In order to avoid an over or under design problem of the electric power system, a simulation program for electric power estimation is adequate.

We propose an on-glass antenna with vertical lines for FM radio reception in a commercial sedan. The proposed antenna consists of vertical lines and multiple horizontal lines that are also used as defroster lines. The proposed antenna structure is optimized with the GA algorithm in conjunction with the FEKO EM simulator. The optimized antenna was built and installed on an Azera test vehicle (Korean model: TG Grandure 270) from Hyndai-Kia Motors and antenna performances such as reflection coefficients, and bore-sight gain are measured in an anechoic chamber. The optimized antenna shows a half power matching bandwidth of 26 % at the center frequency of the FM radio band and an average bore-sight gain of about −10.37 dBi. Then, we take a field test to measure actual received power of FM radio signals. The field test result shows the antenna's minimum received power level of about −80 dBm. The overall measured data show that the optimized antenna can be used as a FM antenna for vehicles.

Vehicle collisions frequently happen at a low-speed. Insurance companies and the RCAR (Research Council for Automobile Repairs) require reducing repair costs and improving occupant safety in a low-speed crash. In order to reduce repair costs in the RCAR test conditions, an energy absorbing device such as the crash box (C/Box) is usually installed. The C/Box is a thin-walled structure attached between the vehicle bumper structure and the side rail. The determination of the C/Box geometry is quite important to absorb the impact energy since the installation space of the C/Box is not very large. In this research, the determination process for the cross-sectional dimensions is proposed to improve the energy absorption efficiency of the C/Box. The proposed process has two steps. First, the cross-sectional dimensions are determined by two ways. One is a parameter study using an orthogonal array and the other is topology optimization.