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The quality of mixture formation in gasoline direct injection (GDI) engines has a significant influence on combustion, emissions and mileage. A new measurement technique was set up at an optically accessible high pressure / high temperature spray chamber to investigate the spatial mass distribution of vapor and liquid phase in order to optimize the stratified engine operation mode. Therefore a laser light sheet is traversed through the spray, the exciplex fluorescence is detected and the tomography results are quantified by the global information of the injected mass, which allows detailed spray investigations with λ-charts. For spray homogeneity analysis a new method based on histogram calculation is presented allowing grid independent comparison of different injector types.

Self-calibration of sensors has become highly essential in the era of self-driving cars. Reducing the sensors’ errors increases the reliability of the decisions made by the autonomous systems. Various methods are currently under investigation but the traditional methods still prevail which maintain a strong dependency on human experts and expensive equipment that consume significant amounts of labor and time. Recently, various calibration techniques proposed for extrinsic calibration for Autonomous Vehicles (AVs) mostly rely on the camera 2D images and depth map to calibrate the 3D LiDAR points. While most methods work with the whole frame, some methods use the objects in the frame to perform the calibration. To the best of our knowledge, majority of these self-calibration methods rely on using actual or falsified ground truth values.

In the last years motorsport is facing a technical revolution concerning the engine technology in every category, from touring car championships up to the F1. The strategy of the car manufacturers to bring motorsport engine technology closer to mass production one (e.g. turbo-charging, downsizing and direct injection) allows both to reduce development costs and to create a better image and technology transfer by linking motorsport activities to the daily business. Under these requirements the so-called Global Race Engine (GRE) concept has been introduced, giving the possibility to use one unique engine platform concept as basis for different engine specifications and racing categories. In order to optimize the performance of this kind of engines, especially due to the highly complex mixture formation mechanisms related to the direct injection, it is nowadays mandatory to resort to reliable 3D-CFD simulations.

The engine designer has to find novel methods to optimize the engine efficiency faster as the engine development cycle is getting shortened due to the continuous growing market demands. Engine optimization involves fine tuning of the various engine parameters and conducting a large number of tests on actual engine test bed. In this paper, modern techniques that have been used to optimize a small 4stroke air-cooled engine performance have been described. The engine has been modelled using one-dimensional thermodynamic engine modelling software (AVL-BOOST). Design of experiments (DoE) tools have been used to optimize the engine variables. The input parameters form an orthogonal array of L27 matrix and the out put characteristics of the engine (responses) have been predicted by using BOOST software. This design matrix has been used to study and optimize thirteen factors in three levels (313).

SLAM (Simultaneous Localization and Mapping) plays a key role in autonomous driving. Recently, 4D Radar has attracted widespread attention because it breaks through the limitations of 3D millimeter wave radar and can simultaneously detect the distance, velocity, horizontal azimuth and elevation azimuth of the target with high resolution. However, there are few studies on 4D Radar in SLAM. In this paper, RI-FGO, a 4D Radar-Inertial SLAM method based on Factor Graph Optimization, is proposed. The RANSAC (Random Sample Consensus) method is used to eliminate the dynamic obstacle points from a single scan, and the ego-motion velocity is estimated from the static point cloud. A 4D Radar velocity factor is constructed in GTSAM to receive the estimated velocity in a single scan as a measurement and directly integrated into the factor graph. The 4D Radar point clouds of consecutive frames are matched as the odometry factor.

Diesel common rail injectors are required to utilize a higher injection pressure and to achieve higher injection accuracy in order to meet increasingly severe emissions, less fuel consumption, and higher engine performance demand. In addition to those requirements, in conjunction with optimized nozzle geometry, a more rectangular injection rate and stable multiple injections with shorter intervals are required for further emissions and engine performance improvement by optimizing the combustion efficiency.

To optimize the tyre contact patch in a sports car, Ferrari has developed an active camber and toe (ACT) system comprising of 4 actuators for the rear axle. This complex and completely new system is difficult to model accurately and for this reason, it was decided to combine a physical prototype with a full vehicle model to carry out the functional tests. The method of combining a virtual model with a physical test is known as hybrid simulation. This functional testing of both the actuators and the vehicle dynamics logic will be performed on an MTS 6DOF bench test prior to physical track testing on a prototype vehicle using Ferrari facility in Maranello, Italy. In support of this functional testing, we will use hybrid simulation techniques with software and methods specifically developed. The planned hybrid test system described in the paper will allow dynamic coupling between the physical bench test and a modified full vehicle simulation model.

As automotive technology has been developed, gear whine has become a prominent contributor for cabin noise as the masking has been decreased. Whine is not the loudest source, but it is of high tonal noise which is often highly unpleasant. The gear noise originates at gear mesh. Transmission Error acts as an excitation source and these vibrations pass through gears, shafts and bearings to the housing which vibrates to produce noise on surrounding air. As microgeometry optimization target to reduce the fundamental excitation source of the noise, it has been favored method to tackle gear whine noise, especially for manual transmission. However, practicality of microgeometry optimization for the planetary gear system has been still in question, because of complex system structure and interaction among multi mesh gear sets make it hard to predict and even harder to improve. In this paper, successful case of whine noise improvement by microgeometry is presented.

Weight reduction and high transmission efficiency demands are getting heavier to manual transmission (MT) for vehicle driving and fuel economy performance. Also comfortable shift feeling and low gear noise level are continuously required by customer because those sensitivity performances are directly recognized by driver which can determine the transmission's merchantability. Newly developed high torque capacity MT is based on serial transmission BG6 which is adopted into a lot of customer' vehicle. This new MT is weight reduced, shift feeling and gear noise performance are highly improved that keeps strong competitiveness in the future. Concerning shift feeling, its smoothness, force balance and cross shift performance are improved and optimized. Also for low gear noise performance, it was reduced to the level which can have advantage to competitor and highly comfortable for passenger vehicle. Those improvement technologies are reported as follows.

In France, the current evolution in the number of road accident victims is less favourable for the moped rider category than for the majority of others. In addition, the proportion of scooters in the moped park is currently considerably increasing. The aim of the research work presented is to consider if an explanation for the bad results for this category of users, in terms of road safety, can be found through the study of the dynamic performances of this type of vehicle. We thus carried out an experiment aimed at comparing the dynamic capacities of a “Classic” moped with those of a “Scooter” model. Two mopeds, one of each type, were fitted with an embedded measurement system. They were driven for several tests on a track by a professional test pilot. The results of this study are more in favour of the “Scooter” moped, which seems to offer equivalent, or even better, dynamic capacities than the “Classic” one.

A 1200-V, 600-A silicon carbide (SiC) JFET half-bridge module has been developed for drop-in replacement of a 600-V, 600-A IGBT intelligent power module (IPM). Advances in the development of SiC field effect transistors have resulted in reliable high yield devices that can be paralleled and packaged to produce high-voltage and high-current power modules not only competitive with existing IGBT technology but the modules have expanded capabilities. A SiC vertical junction field effect transistor VJFET has been produced with the properties of lower conduction loss, zero tail current, higher thermal conductivity, and higher power density when compared to a similarly rated silicon IGBT or any practical SiC MOSFETs previously reported. Three prototype SiC JFET half-bridge modules with gate drivers have been successfully integrated into a three-phase 30-kW (continuous), 100-kW (intermittent) AC synchronous motor drive designed to control a traction motor in an electric vehicle.

Multiple automotive systems are now being developed which require an imager or vision chip to provide information regarding vehicle surroundings, vehicle performance, and vehicle passenger compartment status. Applications include lane departure, lane tracking, collision avoidance, as well as occupant position, impaired driver, and occupant identification. These applications share many requirements, including robust design, tolerance for the automotive environment, built in self-test, wide dynamic range, and low cost. In addition, each application has unique requirements for resolution, sensitivity, imager aspect ratio, and output format. In many cases, output will go directly to vehicle systems for processing, without ever being displayed to the driver. Commercial imager chips do not address this wide spectrum of requirements. A CMOS imager chip has been designed to address these unique automotive requirements.

Metal fiber DPF system is cheaper and more endurable than ceramic filter; however, the regeneration near the wall (outer layer) is difficult because of the heat loss and the less gas flow rate near the wall. In this study, a 3D CFD simulation is performed to find the flow control method for the more uniform mass flux for all filter layer. The major control factors are filter porosity, distribution plate and swirler. By placing the distribution plate in front of the filter the flow near the wall can be increased. The optimum place and size was chosen. The swirler can increase the flow more near the wall.

Getting information about new products and/ or services across the design and manufacturing/ quality assurance community of automotive engineers is one of the greatest challenges of mankind. Since information is the key to progress, an organization's success often depends on its ability to communicate. National and international competition forces designers and manufacturers to continuously innovate and make their product design and manufacturing / assembly processes lean and market driven. Simultaneously the time to market is rapidly shrinking. This means that marketing and sales departments have to explain and sell their increasingly more complex products to an increasingly more educated and globally distributed customer base at a competitive price, and in a short time.

The focus of this paper is to develop an innovative vehicle layout and optimize vehicle body structure with the latest lightweight steel technologies, such as hydro-forming and hot stamping. Our BIW structure achieved a mass savings of 28 kg (−10%) compared to the mass of baseline BIW structure. (Base BIW : MD_Elantra)

The On-Board Diagnostics II (OBD-II) port began as a means of extracting diagnostic information and supporting the right to repair. Self-driving vehicles and cellular dongles plugged into the OBD-II port were not anticipated. Researchers have shown that the cellular modem on an OBD-II dongle may be hacked, allowing the attacker to tamper with the vehicle brakes. ADAS, self-driving features and other vehicle functions may be vulnerable as well. The industry must balance the interests of multiple stakeholders including Original Equipment Manufacturers (OEMs) who are required to provide OBD function, repair shops which have a legitimate need to access the OBD functions, dongle providers and drivers. OEMs need the ability to protect drivers and manage liability by limiting how a device or software application may modify the operation of a vehicle.

In gasoline direct injection engines with stratified-combustion strategies only a short time is available for mixture preparation. Therefore, investigations are carried out to evaluate the influence of high injection pressure up to 50 MPa in order to optimize the mixture preparation. Two types of multi-hole injectors are analyzed in a pressure vessel under various pressure and temperature conditions. Laser light sheet visualization technique is applied in order to determine spray characteristics like shape, angle, penetration depth and spray width. To determine the velocity of the air surrounding the spray, a PIV (Particle Image Velocimetry) measurement technique is used. Droplet sizes and velocities are measured with a Phase Doppler Anemometer (PDA) in different positions in the spray center and at the spray edge. Spray visualization experiments show the influence of evaporation on spray propagation at higher temperatures.

With the improved safety performance of vehicles, the number of accidents has been decreasing. However, accidents due to driver distraction still occur, which means that there is a high need to determine whether a driver is properly looking at the surroundings. Meanwhile, with the trend toward partial automatic driving of vehicles in recent years, it is also urgently required that the state of the driver be grasped. Even if automatic driving is not installed, it is desired that the state of the driver be grasped and an application for control be performed depending on the state of the driver. Under these circumstances, we have built an algorithm that determines of the direction a driver is looking, to make a basic determination of whether or not the driver is in a state suitable for safe driving of the vehicle.

A combined biodynamic and vehicle model is used to assess the vibration and performance of a human operator performing driving and other tasks. The other tasks include reaching, pointing and tracking by the driver and/or passenger. This analysis requires the coordinated use of separate and mature software programs for anthropometrics, vehicle dynamics, biodynamics, and systems analysis. The total package is called AVB-DYN, an acronym for Anthropometrics, Vehicle and Bio-DYNamics. The biodynamic component of AVB-DYN is described, and then compared with an experiment that studied human operator in-vehicle reaching performance using the U.S. Army TACOM Ride Motion Simulator.

A biomechanical model has been developed using dynamic programming as a solution technique. The criterion selected for optimization is power-generated to perform a movement. The model predicts the position of the hand in space while performing simple movements, but the study indicates a need for more detailed considerations of model assumptions. However, the basic assumptions and the principles of theoretical mechanics used in dynamic analyses of man in motion continue to be valid and are not refuted by this study.