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BMW VALVETRONIC technology is able to maintain the most important measures to reduce emissions. The further optimized charge movement created by VALVETRONIC stabilizes the combustion in the catalyst heating mode with extremely retarded ignition timing. When the engine is warm the high residual gas tolerance ensures very low Engine-Out NOx emissions and at the same time a low level of hydrocarbons. The atomization of fuel droplets due to high flow velocity in the valve gap area leads to improved mixture formation and reduced wall wetting. Engine-Out HC emissions in a cold engine are therefore reduced. Combined, the emission measures achieve robust and efficient emission control. In combination with additional after-treatment like secondary air system and catalysts using high cell density VALVETRONIC engines form an excellent base for SULEV emission regulations without neglecting the typical BMW claim of efficient dynamics.

Toyota Motor Corporation has developed a new six-speed automatic transaxle (U660E) for Front Wheel Drive (FWD) vehicles. Component parts of U660E are completely redesigned. By combining an innovative gear train which Toyota originally invented and newer technologies, U660E has achieved outstanding fuel economy, smooth and quick shift performance and quietness in a lightweight package among Automatic Transaxles (AT) with similar torque capacity.

In the past few years, the demands for more complex system development and the ever-increasing requirement for hardware and software improvements have increased the need for a virtual embedded system where the hardware, microcontroller and software co-exist at the simulation level. This paper discusses the implementation of an approach that allows the full simulation of the embedded system. In the scope of this paper the definition of an embedded system refers to the electro-mechanical plant, the microcontroller, the peripherals and the software. The sensors and actuators are developed with a conservative type simulator such as Saber from Synopsys. The microcontroller and the attached peripherals are developed and modeled with the Comet environment from VaST. The microcontroller simulator is instruction cycle accurate. We are describing an innovative concept that will allow co-simulation between the two simulators.

Harmonization of systems and parts leads to platform strategies as already known for years in the automotive industry. With respect to Electrical and Electronic Distribution Systems (EEDS), the investigations are aiming at electrical systems and components, e.g. Electronic Control Units (ECU), sensors, actuators, switches and connectors, to be used as carry-over parts for increasing the volume, the quality and thus reducing cost. Common architectures are going through changes during their lifecycle. New functions are integrated due to customer needs or for upgrading. To achieve the most efficient way of integration, various factors have to be considered. Factors are e.g. fusing concept, wire routing (topology) and communication network. To handle these and other factors, only processes with an appropriate level of software support are able to provide accurate and reliable results.

Today's advanced technology engines have a high content of electronic actuation requiring sophisticated real-time embedded software sensing and control. To enable research on such engines, a system with a flexible engine control unit (ECU) that can be rapidly configured and programmed is desired. Such a system is being used in the Advanced Internal Combustion Engine (AICE) Laboratories at Michigan Tech University (MTU) for research on a multi-cylinder spark-ignited gasoline, a high pressure common rail diesel and a single cylinder alternative fuels research engine. The system combines a production ECU with a software development system utilizing Mathworks Simulink/Stateflow © modeling tools. The interface in the Simulink modeling environment includes a library of modeling and interface blocks to the production Operating System (OS), Low Level Drivers (LLD) and CAN-based calibration tool.

A physics-based simulation program developed by IAV is used to calibrate the torque structure and cylinder charge calculation in the electronic control unit of SI engines. The model calculates both the charge cycle and combustion phase based on flow mechanics and a fractal combustion model. Once the air mass in the charge cycle has been computed, a fractal combustion model is used for the ongoing calculation of cylinder pressure and temperature. The progression of cylinder pressure over the high and low-pressure phases also provides information on engine torque. Following the engine-specific calibration of the model using elemental geometric information and reduced test bench measurements, the physical engine properties can be simulated over the operating cycle. The calibrated model allows simulations to be carried out at all operating points and the results to be treated as virtual test bench measurements.

The prototype solid particle counting system (SPCS) has been used to study solid particle emission from gasoline and diesel vehicles. As recommended by the PMP draft proposal, exhaust is diluted by a Constant Volume Sampler (CVS). The SPCS takes the sample from the CVS tunnel. Transient test cycles such as EPA FTP 75, EPA HWFET (EPA Highway Fuel Economy Cycle), and NEDC (New European Driving Cycle) were tested. The repeatability of the instrument was evaluated on the diesel vehicle for three continuous days. The instrument exhibits good repeatability. The differences for the EPA ftp 75, the EPA HWFET, and the NEDC in three continuous tests are ± 3.5%. The instrument is very sensitive as well and detects the driving differences. A large number of solid particles are found during the hard acceleration from both the gasoline and the diesel vehicles. Solid particle emissions decrease quickly at deceleration and when vehicles approach constant speed.

A prototype solid particle counting system (SPCS) has been developed in Horiba. It measures the engine exhaust solid particle number emissions in real-time. The instrument is designed to follow the recommendation in the PMP proposal for solid particle number emissions measurement on Light-duty diesel vehicles. Two wide range continuous diluters, which were developed during this project, have been used as cold and hot diluters, respectively. The accuracy of the dilution ratio is normally ± 4% for the designed range. The instrument has low particle losses, and exhibits over 95% penetration for solid particles. The new instrument has functions such as, normal measurement, dilution ratio control, daily calibration for condensation particle counter (CPC), etc. These functions have been automated to make the instrument's operation simple.

This article main has discussed the design and the manufacturing of integrating Local Interconnect Network (LIN) and the Adaptive Front-lighting System (AFS); in the headlamp controller part we have applied the LIN2.0 Single-Master/Multi-Slave framework. In this experiment we use the host controller as Master's node, and the right & left headlamps and the auxiliary angle lamp to play the Slave duty. In addition, sensors installed in the car's system include the steering-wheel turning angle using the Controller-Area-Network (CAN2.0) interface and the automobile's horizontal sensing signal. Therefore, the main controller of headlamp is the gateway of CAN and LIN, applied to exchange information between the different networks.

This paper aims for a seamless development process for automotive body network system development with model-based approach. It also describes a generic software architecture that provides clear-boundaries between the software components and that can also act as a guide for each development phase. The CASE tool Statemate is used for feature behavioral modeling and verification. NodeAllocator builds the ECU models by mapping the behavioral model and physical network architecture. The virtual prototypes and the basic bus communication information are created and validated using software in loop simulation. The validated functional models are refined for implementation models and MicroC is used for application task code, OS design and software integration.

For many racing teams the use of Computational Fluid Dynamics (CFD) as a design tool could mean a very expensive investment. CFD analysis of the complex separated flows associated with a race car would typically require extensive resources. Through the design of aerodynamics for a Formula SAE race car, this paper illustrates the use of less extensive CFD along with the wind tunnel as a tool that reduces design time. Various meshing techniques are analyzed that do not require extensive computational resources and are fairly simple to implement. The results obtained from these methods are compared to experimental results from wind tunnel tests. For the design of wings the results show that the coefficient of lift can be predicted fairly accurately to within 10% of the experimental value, but the coefficient of drag is not predicted very well. It is also shown that the design of an effective aerodynamics package can be accomplished with these fairly simple techniques.

While race cars run in a highly dynamic environment, aerodynamic testing through state of the art wind tunnel tests, as well as CFD analyses, are mostly performed under static or stationary conditions. Therefore, other than track data, only very limited data are available on time resolved aerodynamic forces and pressures for a moving car. To investigate these effects a new model manipulator was developed which allows substantial pitch and heave movements up to 20Hz. Wind tunnel tests with a former LeMans type race car model have shown that the difference between a steady state and a true dynamic analysis is significant.

Using a prototype of terrain car as example, a process of flow simulation around a vehicle with rotating wheels is described by using a professional CFD (Computational Fluid Dynamics) software. The influence of the wheels motion on main aerodynamic characteristic of the car, drag, is studied in two ways, commonly used in wind tunnels [10], respectively with the moving wall approach and with the aid of the rollers for the wheels rotation. The conclusions are demonstrated by the results using the relative drag increment and by the computergraphics visualizations. There are also presented some considerations concerning the importance of the rotating wheels in aerodynamics of the road vehicle and the opportunity to simulate it in a virtual environment. The present contribution is a companion paper by Huminic & Chiru (2004).

The aim of this report is to present the results obtained from the wind tunnel tests performed in the BMW wind tunnel regarding the pressure distribution on a rotating wheel. The acquired data is used to examine its flow topology for the “open” and “enclosed” cases and determine the wheel drag, lift and side forces by integrating the pressure distribution on its surface. The investigation concerned such measurements on a half scale model wheel. Its pressure distribution was identified with and without the presence of a racecar body. The wheel was also mounted on a half scale passenger car body and pressure measurements were taken with and without a wheel spoiler. After the pressure distributions were known for all configurations, the aerodynamic forces generated were determined. The influence of boundary layer thickness on them was also investigated. A better understanding of the forces the model wheel is subjected to is gained.

The initial design of an aerodynamics package for a Formula SAE car is described. A review of Formula SAE rules relating to aerodynamics is used to develop realistic parameters for the specification of front and rear inverted airfoils, or ‘wings’. This wing package is designed to produce maximum downforce within the stated acceptable limits of increased drag and reduced top speed. The net effect of these wings on a Formula SAE car's performance in the Dynamic Events is then predicted. A companion paper [1] describes in detail, the CFD, wind tunnel and on-track testing and development of this aerodynamics package.

A new human machine interface (HMI) switch control concept was proposed and evaluated with a driver simulator-based simulation analysis as described in the study of Kiyotaka Sasanouchi [1]. This new concept provides an integrated interface for the vehicle driver to operate on-board devices such as audio, multimedia, HVAC, and navigation systems. To further study and evaluate the benefits of the new concept and more importantly the detailed design factors, a prototype system has been developed and then installed in a production vehicle. The experience learned through this development project is presented in this paper. Some key design issues are addressed, including the multi-functional switch design, menu tree optimization, visual feedback display presentation, and vehicle system interface. Results from an internal customer test ride and survey are also presented to demonstrate the performance and benefits of the new HMI concept design.

In this research, driver risk (subjective feeling of danger) during pylon slalom and drift turning was evaluated by measuring the amount of driver perspiration. The result (the product of the amount of maximum perspiration and the perspiration amount area at the unit running time) is believed to correspond to a subjective rating of the feeling of danger. Moreover, a peculiar phenomenon was observed during drift cornering in which a large degree of fear was experienced if there was a possibility that the vehicle might spin, thus considerably increasing the amount of perspiration. Here, perspiration amount area shows the total amount of perspiration, additional to baseline levels, over a given time frame. And, unit running time shows the same as saying ‘averaged over time’

Vehicle manufacturers are increasingly demanding an accurate preemptive clutch actuation device to distribute drive torque to secondary axles/wheels. The primary driver behind the need for accuracy is the desire to affect the vehicle handling through active torque distribution. Additionally, the ability to preemptively apply a clutch, independent of differential axle rotation, is also required to assure vehicle stability from launch on various surfaces. Other requirements of such a torque transfer device include fast response time, low hysteresis, low drag torque, and low mass.

This paper describes the process and simulation tool chain applied to the design for production of a rear axle with a variable torque biasing capability. Based upon a proven core design (successfully demonstrated in 2004) comprising a novel epicyclic gear arrangement, several variants have been proposed using alternative actuation technologies to achieve bi-directional control of torque bias. The specific design described here includes two concentric wet-plate brakes of less than 200 Nm that control the left-right bias of up to 1400 Nm in a compact and modular design. Recorded GPS data was replayed in a vehicle simulation to derive the range of yaw moment that would be usefully generated by the rear axle to control the lane-keeping and slip angle of the vehicle.

With recent advances in microprocessors and data storage technologies, vehicle users can now bring or access large amounts of data in vehicles for purposes such as communication (e.g. e-mail, phone books), entertainment (e.g. music and video files), browsing and searching for information (e.g. on-board computers and internet). The challenge for the vehicle designer is how to design data displays and retrieval methods to allow data search and manipulation tasks by managing driver workload at safe acceptable levels. This paper presents a data retrieval menu system developed to assess levels of screens (depth of menu) that may be needed to select required information when a vehicle is equipped with the capability to access audio files, cell phone, PDA, e-mail and “On-star” type functions.