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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.

Numerical durability analysis is the only approach that can be used to assess the durability of vehicles in early stages of development. In these stages, where there are no physical prototypes available, the road wheel forces (or spindle forces) for durability testing on Belgian PG (Proving Ground) must be predicted by VPG (Virtual Proving Ground) or derived from the measured forces of predecessor vehicles. In addition, the tuning parts and geometry are not fixed at these stages. This results in the variation of spindle forces during the development stages. Therefore, it is not reasonable to choose the forces predicted at a specific tuning condition as standard forces. It is more reasonable to determine the standard forces stochastically using the DB of the measured forces of predecessor vehicles. The spindle forces measured or predicted on Belgian PG are typically stationary random.

As the original engine sound is usually not enough to satisfy the driver’s desire for a sporty and fascinating sound, Active Noise Control (ANC) and Active Sound Design (ASD) have been great technologies in automobiles for a long time. However, these technologies which enhance the sound of vehicles using loud speakers or electromagnetic actuators etc. lead to the increase of cost and weight due to the use of external amplifiers or actuators. This paper presents a new technology for generating a target sound by the active control of a permanent magnet synchronous motor (PMSM) of a mass-production steering system. The existing steering hardware or motor is not changed, but only additional software is added. Firstly, an algorithm of this technology, called Active Sound Generation (ASG), is introduced which is compiled and included in the ECU target code. Then the high frequency noise issue and its countermeasures are presented.

In order to extend the operability limit of the gasoline compression ignition (GCI) engine, as an avenue for low temperature combustion (LTC) regime, the effects of parametric variations of engine operating conditions on the performance of six-stroke GCI (6S-GCI) engine cycle are numerically investigated, using an in-house 3D CFD code coupled with high-fidelity physical sub-models along with the Chemkin library. The combustion and emissions were calculated using a skeletal chemical kinetics mechanism for a 14-component gasoline surrogate fuel. Authors’ previous study highlighted the effects of the variation of injection timing and split ratio on the overall performance of 6S-GCI engine and the unique mixing-controlled burning mode of the charge mixtures during the two additional strokes. As a continuing effort, the present study details the parametric studies of initial gas temperature, boost pressure, fuel injection pressure, compression ratio, and EGR ratio.

In this paper, a design procedure for the optimized light weight front cross member, which is a sub frame of the car chassis, without sacrificing basic functional requirements is presented. As the first step, optimal structural integrity was calculated and extracted using a CAE technique with the available volume constraint of the package layout. Quantitative design loads for the cross member was achieved by measurement. Dynamic load analysis using ADAMS was also performed to determine the loads. Later, these calculated loads were applied to the FEM stress analysis of the cross member. Furthermore, durability analysis was also performed using load profile database measured from ‘Hyundai Motor Co. Proving Ground’. Four constant amplitude durability tests and two static tests were performed on the cross member prototypes to confirm design reliability.

Emission of carbon dioxide from mobile sources seriously concerned to solve greenhouse effect and high price of gasoline in some countries have resulted in the development of lean-burn concept engine. In spite of many studies on the lean deNOx catalyst, we have no clear solution to obtain high fuel economy and high efficiency of NOx conversion in lean-burn application. This paper describes applicability and problems of NOx adsorber system to partial lean-burn vehicle, the development of three-way catalyst with improvement of washcoat technology based on three-way catalyst used for gasoline application, and comparison test results of evaluations is synthesized gas activity test, Federal Test Procedure (FTP) test, etc. This study shows improved three-way catalysts in partial lean- burn vehicle have max. 89% of NOx conversion in FTP without adding rich spike and regeneration functions to engine management system.

Recently weight reduction is increasingly needed in automotive industry to improve fuel efficiency and to meet a CO2 emission requirement. In this paper, we prepared composite body panels for the lightweight vehicle based on a small passenger car. Fender, roof, door, side outer panel, and tailgate are made from hand layup using a glass/carbon hybrid reinforcement. Hood is made from low pressure sheet molding compound (SMC) to investigate feasibility of mass production. Both hand layup and low pressure SMC materials are newly developed and their physical properties are examined. CAE simulation was done for strength analysis and optimization of thickness for the body panels.

Generally, the widely used hydraulic control system in automatic transmissions is pulse width modulation (PWM) type. It consists in a PWM solenoid valve and a reducing type second stage valve, so called pressure control valve (PCV), to amplify pressure or flow rate. In this study, the mathematical models of the PWM solenoid valve and the PCV with moderate complexity are proposed. Then, their behavior is analyzed from the steady state characteristics. Finally, we find that there are good matches between the dynamic simulation results and the experimental data.

Hyundai Motor Company has developed hydrogen fuel cell vehicles (FCV) based on its SUV, Santa Fe. As the hydrogen fuel cell power plant runs at near ambient pressure, parasitic loss due to its operation is fully minimized and the noise level of the air supply subsystem is extremely low. The Santa Fe FCV has been built to feature roomy passenger space and cargo capacity identical to that of a standard, gasoline-powered Santa Fe, because of its compact fuel cell power plant. In addition, lightweight aluminum body-components help to keep a power-to-weight ratio similar to that of a conventional SUV. Hyundai Motor Company, as a full member of California Fuel Cell Partnership, is now operating the Santa Fe FCV's on real roads in California. In this paper, the configuration and performance test results of the Santa Fe FCV will be described.

Fuel tank in vehicle must hold the fuel in a stable way under any driving condition. However, the fuel tank might not conserve the fuel firmly in case a crack emerged while the fuel tank is exposed to different driving condition. Basically, when the engine is in purging at a normal ambient temperature before fuel boiling, the pressure inside the fuel tank decreases. However, the pressure inside a fuel tank increases while a vehicle is driven at extreme hot ambient temperature as fuel is boiling. This repetitive pressure change in the fuel tank comes with fuel tank’s physical expansion and shrink, which would cause a damage to the fuel tank. The main purpose of this research is to investigate the root cause of why fuel tank cracks at a fatigue point. We also aim to set up the method of how to test durability of the fuel tank in association with the pressure inside the tank.

Currently, diesel engine-out exhaust NOx emission level prediction is a major challenge for complying with the stricter emission legislation and for control purpose of the after-treatment system. Most of the NOx prediction research is based on the Zeldovich thermal mechanism, which is reasonable from the physical point of view and for its simplicity. Nevertheless, there are some predictable range limitations, such as low temperature with high EGR rate operating conditions or high temperature with low EGR rates. In the present paper, 3 additional considerations, pilot burned gas mixing before the main injection; major NO formation area; concentration correction, were applied to the previously developed real-time NO estimation model based on in-cylinder pressure and data available from ECU. The model improvement was verified on a 1.6 liter EURO5 diesel engine in both steady and transient operation.

A nano-sized PM and THC emission characteristics were investigated according to the fuel injection strategy such as a pressure and timing in the GDI engine. On the part-load condition, the particulate emissions exhibited a strong sensitivity to the injection timing. The fuel injection pressure also had a great association with the nano-particles and THC. A size of PM exhausted from the GDI engine located near 10nm on the part-load. In contrast, accumulation mode particles within 60 - 80nm mainly exhausted during the cold transient start phase. Increment of fuel injection pressure positively affected on the nano-particle and THC emissions during the start of the engine, as well.

Fluctuation in the sound pressure level of the interior noise of an on-road vehicle is always caused by unpredictable factors such as wind gusts, traffic, roadside obstacles, and changing drive-by-drive conditions, and is hence, not reproducible in nature. Since the human brain is known to be more sensitive to noise that is amplitude-modulated than noise at a steady level [1], it is important to evaluate and improve the NVH performance of a vehicle in terms of the fluctuating interior noise likely to be experienced by drivers or users. To this end, an evaluation system was developed as part of this study, the details of which are presented in this paper. The system is composed of hardware for database storage and replay of sounds, and software for synthesizing the noise signals. For given wind tunnel test results, the evaluation system yields a wind noise model that can synthesize wind noise signals for any wind scenario.

Although tire forces are important as factors governing the behavior of a vehicle, current chassis control systems have used tire forces indirectly estimated. Hence, this research developed Intelligent Tire System (i-Tire) that can measure tire forces directly. This system used a deform gage and a surface acoustic wave (SAW) sensor, which are capable of passive radio communication. The performance of this developed system was tested with a tire test system (MTS Flat Trac) and a vehicle test.

This report explains the basic theory of designing the accelerating durability test road and the role of each factors contributing to the test road surface profile. Also this road is designed by considering the charactors of vehicle suspension system and conditions of driving. In test road, the factors affecting to the vehicle structural durability are correlation among surface shape of road profile, frequency of vehicle suspension system,distribution of axle twist angle and vibration of road profile height. Road PSD magnitude and frequency delay is used to control these factors relation.

Extensive researches are being performed on a world wide basis with the aim of enhancing occupant protection on the side impact. The test methodology for side impact can be divided into two general groups; Sub-System Tests Full Scale Tests. However, the advantages of full scale test is that it is possible to make an integrated statement on the protective potential of the structural stiffness of the struck vehicle and the padding for a selected collision speed and type of collision. The advantages of sub-system test methodology can be simulates more exactly for wide range of accident(i.e. collision directions, impact points etc.). The latter test procedure can be carried out at a relatively earlier stage in the development of a new vehicle, and also can be reduce the time and cost. The Computer Controlled Composite Test Procedure(CC-CTP) presented in this paper has been developed by CCMC (Committee of Common Market Automobile Constructors).

It is necessary for vehicle horns not only to satisfy regulations on the sound level but also to fulfill various demands related with sound quality. For example, a disk type horn which is attached on most of small size vehicles has been required to improve its sharp feeling sound. However, the improvement of horn sound has been deterred mainly due to the deficiency of the understanding on how design factors are related with emotional judgments on horn sound. In addition, a proper CAE tool is not available in the process of horn design since it is difficult to describe multi-physical phenomena engaged with horns. The purpose of this study is to improve the sound quality of a disk type horn. In order to achieve this goal, firstly, acoustic characteristics of horns were obtained through a series of experiments. In addition, various sound quality metrics were examined in order to derive design factors affecting sound quality enhancement.

A model based control algorithm for the pressure control type CVT has been developed. First, a P-line is proposed from the steady state relationship between the primary and secondary pressure for the given speed ratio to predict the shift performance. The P-line shows the pressure difference from the steady state primary pressure to the maximum(or minimum) pressure available for the given secondary pressure. It is found from the P-line that the bigger the pressure difference, the faster the shift speed. Based on the steady state characteristics of the pressure control type ratio control valve(RCV), the model based control algorithm is proposed. In the model based control, ratio control solenoid valve(RCSV) control duty is supplied in the feedforward loop.

As CO2 legislation tightens, the next generation of turbocharged gasoline engines must meet stricter emissions targets combined with increased fuel efficiency standards. Recent studies have shown that the following technologies offer significant improvements to the efficiency of turbocharged GDI engines: Miller Cycle via late intake valve closing (LIVC), low pressure loop cooled EGR (LPL EGR), port water injection (PWI), and cylinder deactivation (CDA). While these efficiency-improving technologies are individually well-understood, in this study we directly compare these technologies to each other on the same engine at a range of operating conditions and over a range of compression ratios (CR). The technologies tested are applied to a boosted and direct injected (DI) gasoline engine and evaluated both individually and combined.

As CO2 legislation tightens, the next generation of turbocharged gasoline engines must meet stricter emissions targets combined with increased fuel efficiency standards. Promising technologies under consideration are: Miller Cycle via late intake valve closing (LIVC), low pressure loop cooled exhaust gas recirculation (LPL EGR), port water injection (PWI), and cylinder deactivation (CDA). While these efficiency improving options are well-understood individually, in this study we directly compare them to each other on the same engine at a range of operating conditions and over a range of compression ratios (CR). For this purpose we undertake a comprehensive simulation of the above technology options using a GT-Power model of the engine with a kinetics based knock combustion sub-model to optimize the fuel efficiency, taking into account the total in-cylinder dilution effects, due to internal and external EGR, on the combustion.