Search Results

A cooperation of several research partners supported by the German Federal Ministry of Research and Education proposes a new active matrix LED light source. A multi pixel flip chip LED array is directly mounted to an active driver IC. A total of 1024 pixel can be individually addressed through a serial data bus. Several of these units are integrated in a prototype headlamp to enable advanced light distribution patterns in an evaluation vehicle.

This paper will outline the results of a study performed to analyze the market introduction of x-by-wire applications in the context of weak global industry environment, technological and legislative challenges, standardization issues and end customer benefits. This paper attempts to provide a bird-view on influence factors and impacts for the x-by-wire market, including e.g. the end customer's acceptance and legal environment driving further development in specific areas. Further, major driving forces on semiconductor/component level will be outlined regarding e.g. pin-count, computation performance and heat dissipation, but also possible scenarios and solutions towards safe and efficient system design and partitioning.

The weight reduction and noise refinement of powertrain has been major concern in automotive industry although they are known as self trade-off. This paper presents various methods to deal with those problems for new Hyundai 1.5 liter powertrain. It was possible to reduce the weight of powertrain by using plastic for both headcover and intake manifold, aluminum for crankshaft damper pulley and stainless steel for exhaust manifold and by reducing the general thickness of cylinder block On the other hand, the noise refinement of vibration in the powertrain was made by optimizing the engine structure and by adapting the hydraulic lash adjuster valve train system, which was proved to be effective in mechanical noise of engine.

Automotive powertrain and safety systems under design today are highly complex, incorporating more than one CPU core, running with more than 100 MHz and consisting of several 10 million transistors. Software complexity increases similarly making new methodologies and tools mandatory to manage the overall system. The use of accurate virtual prototypes improves the quality of systems with respect to system architecture design and software development. This approach is demonstrated with the example of the PCP/GPTA subsystem for Infineon's AUDO-NG powertrain controllers.

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.

The vehicle vibrations result from the exciting forces which are caused by air force, engine firing, tire mass unbalance, and tire uniformity. Especially, the shake and shimmy phenomena in the steering system are closely related to the vehicle vibration, the tire unbalance, and the tire uniformity. This paper presents the shimmy phenomenon due to the tire mass unbalance and the tire uniformity in order to investigate their effects.

The electrical power system is the vital lifeline to most of the control systems on modern vehicles. The demands on the system are highly complex, and a detailed understanding of the system behavior is necessary both to the process of systems integration and to the economic design of a specific control system or actuator. The vehicle electric power system, which consists of two major components: a generator and a battery, has to provide numerous electrical and electronic systems with enough electrical energy. A detailed understanding of the characteristics of the electric power system, electrical load demands, and the driving environment such as road, season, and vehicle weight are required when the capacities of the generator and the battery are to be determined for a vehicle. An easy-to-use and inexpensive simulation program may be needed to avoid the over/under design problem of the electric power system. A vehicle electric power simulator is developed in this study.

In this paper, four different levels of finite element models of a full vehicle were developed for ride comfort and brake judder dynamics analysis. The differences between the models are how elasticity of various vehicle components is modeled. The dynamic analysis was performed considering nonlinear effects for the different levels of models. The nonlinear effects were characterized by frequency and amplitude dependent stiffness and damping values of hydraulic engine mounting, suspension lower control arm bushing, tire, shock absorber, and suspension friction. At each modeling level, simulation results were compared to those of test measurements. The differences of the analysis results of these models and the effect of nonlinear characteristics were investigated. The developed models were applied to ride comfort and brake judder dynamics analysis.

A vehicle drifts due to several reasons from its intended straight path even in the case of no steering input. The multibody dynamic analysis of vehicle drift during accelerating and braking are performed. This paper focuses on modeling and evaluating effects of suspension parameters, differential friction, engine mounting and C.G. location of the vehicle under multibody dynamic simulation environment. Asymmetry of geometry and compliance between left and right side is considered cause of drift. The sensitivities of the suspension parameters are presented for each driving condition. In case of acceleration, the interaction of differential friction and driveshaft stiffness and their influence on drift are also studied. For braking condition, suspension parameters such as initial toe variation of rear coupled torsion beam axle type suspension and kingpin inclination deviation of front suspension are studied including the braking force difference.

The worldwide automotive industry is currently preparing for a market introduction of hydrogen-fueled powertrains. These powertrains in fuel cell electric vehicles (FCEVs) offer many advantages: high efficiency, zero tailpipe emissions, reduced greenhouse gas footprint, and use of domestic and renewable energy sources. To realize these benefits, hydrogen vehicles must be competitive with conventional vehicles with regards to fueling time and vehicle range. A key to maximizing the vehicle's driving range is to ensure that the fueling process achieves a complete fill to the rated Compressed Hydrogen Storage System (CHSS) capacity. An optimal process will safely transfer the maximum amount of hydrogen to the vehicle in the shortest amount of time, while staying within the prescribed pressure, temperature, and density limits. The SAE J2601 light duty vehicle fueling standard has been developed to meet these performance objectives under all practical conditions.

This paper will describe different types of short circuit conditions, how they affect power semiconductor devices, and how to detect and safely mitigate the event.

Recently, the demand for improving the merchantability of hood open system has been increasing. A novel concept hood open system was proposed by Hyundai Motor Company (HMC) in 2012, which was based on a two-step open latch mechanism. The new hood opening mechanism satisfies Safety laws and improves merchantability.

Automotive applications classed as safety-related or safety-critical are now important differentiating technologies in the automotive industry. The emergence of safety standard ISO 26262 underlines the increasing importance of safety in automotive software. As well as functional requirements, hard real-time requirements are of crucial importance to safety-related software as there is a need to prove that the system functionality is fulfilled, even in worst-case scenarios. Measurement-based WCET (Worst-Case Execution Time) analysis combines on-target timing measurements with static analysis of program structure to calculate predicted worst-case paths and times. This is in contrast to traditional end-to-end timing measurements, which give no confidence that the worst-case path is actually tested and no insight into the location of any timing problems that do emerge.

Integration scenarios for ECU software become more complicated, as more constraints with regards to timing, safety and security need to be considered. Multi-core microcontrollers offer even more hardware potential for integration scenarios. To tackle the complexity, more and more model based approaches are used. Understanding the interaction between the different software components, not only from a functional but also from a timing view, is a key success factor for high integration scenarios. In particular for multi-core systems, an amazing amount of timing data can be generated. Usually a multi-core system handles more software functionality than a single-core system. Furthermore, there may be timing interference on the multicore systems, due to the shared usage of buses, memory banks or other hardware resources.

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.

It has been recently reported that the crankshaft vibration provides the main exciting source in the power train vibration. This paper presents the analytical method for the vibration of crankshaft by using the finite element method. The optimization process is employed so that the beam model of the crankshaft can have the same natural frequencies as those of solid model on the free-free condition. The mode analysis of the crankshaft whirling is made in the consideration of the gyroscopic effect and the changes of the natural frequencies are also studied with the increase of the engine speed. Finally, the forced vibration of the crankshaft is solved on the time domain and the results are compared with those of the experimental measurements of bending moment by using the strain gage. This crankshft system model can be used to analyze the forced vibration of the full power train as well.

High pressure fuel injection systems, such as common rail (CR) systems and electronically-controlled unit injector (EUI) systems, have been widely applied to modern heavy duty diesel engines. They are shown to be very effective for achieving high power density with high fuel efficiency and low exhaust gas emissions. However, the increased peak combustion pressure gives additional structural stress and thermal load to engine structure. Thus, proper material selection and thermal analysis of engine components are essential in order to meet the durability requirements of heavy-duty diesel engines adopting a high pressure injection system. In this paper, thermal analysis of a 12.9 ℓ diesel engine with an EUI system was studied. Temperatures were measured on a cylinder head, a piston and a cylinder liner. A specially designed linkage system was used to measure the piston temperatures. A radio-tracer technique was also used to verify the rotation of piston rings.

To simulate the car-to-car crash accidents in the real field, the Autonomous Driving System was developed. This system consists of communicating, sensing, accelerating, braking, steering and data recording subsystems. All these were designed to be compact, light and collapsible, so that the crash characteristics of test vehicle were not affected. The velocity performance of the system covers from 10 kph to 100 kph within ± 0.5 kph error, and the lateral deviation is constrained within ± 20 mm. With this system, several frontal offset and side car-to-car crash tests were carried out successfully. Deformations, injury levels, deceleration signals and dynamic behaviors during crash were typically investigated. And the dynamic behaviors were compared with the simulation results of EDSMAC. Car-to-car crash tests between small and large vehicles with different masses were carried out and the effects on the compatibility were investigated.

This paper presents an in-vehicle information system, AVICS in development. With AVICS, the driver could get the various information on traffic, news, weather, restaurants, and so on, which the AVICS information center provides via mobile telecommunication network. The driver requests the information to operator in center by voice with hands-free system or by handling the menu offered in the form of web-page. The in-vehicle unit for AVICS is designed to interface with wireless network with a built-in RF MODEM, to control NAVI system, and to display the information on the LCD monitor of AV system. The Internet browser is customized to parse specific HTML tags, application software is realized on 32-bit RISC processor. In this paper, we will overview the concept of AVICS and focus on development of in-vehicle unit of AVICS.