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Fillet and plug weld are commonly used in structural applications in commercial heavy vehicles. This paper is primarily concerned with an investigation of the full field deformations fields in fillet and plug welds using three dimensional digital image correlation (3D-DIC). Two identical vehicle parts are constructed using a fillet weld for one specimen, and a plug weld for the other. The specimens are loaded under quasi-static conditions with simultaneous measurement of load, displacements and strain gage measurements. Strain gage locations are selected based on the results of a finite element analysis model. 3D-DIC measurements are constructed using a two camera setup. Thus, 3D-DIC measurements are compared to strain gage measurements and finite element predictions. The effectiveness of the non-contact full field method is evaluated for application to studying the weld details considered and potential for fatigue damage and durability.

Comfort is a main factor in customer's decision when buying a car. The seat plays a very important role, as it is the interface between occupant and vehicle. Pressure distribution is today's most common approach to characterize seat comfort, but it shows limitations. Analysis of human inter-tissue stress tends to be relevant for an objective comfort assessment. This paper presents the construction and validation of a CAE human model, based on Magnetic Resonance Imaging scans and in-vivo tests data. Correlation between objective criteria and subjective evaluation will be investigated, comfort performance of a real seat will be predicted.

This study was conducted to develop and validate a multidimensional measure of shift quality as perceived by drivers during kick-down shift events for automatic transmission vehicles. As part of the first study, a survey was conducted among common drivers to identify primary factors used to describe subjective gear-shifting qualities. A factor analysis on the survey data revealed four semantic subdimensions. These subdimensions include responsiveness, smoothness, unperceivable, and strength. Based on the four descriptive terms, a measure with semantic scales on each subdimension was developed and used in an experiment as the second study. Twelve participants drove and evaluated five vehicles with different gear shifting patterns. Participants were asked to make kick-down events with two different driving intentions (mild vs. sporty) across three different speeds on actual roadway (local streets and highway).

A new numerical method is developed to predict the movement of a valve induced by the flow-induced force and pressure field around a valve. It solves the governing equations of fluid dynamics coupled with the motion equation of the valve. We apply this method to predict the motion of a spool valve in a valve body of an automatic transmission. In addition, the effectiveness of design parameters is found to achieve the design goal that reduce the discharge flow rate and flow-induced force. Finally, the optimized design of valve with better performance is suggested.

Structure-born vibrations are often required to be localized in a complex structure, but in such dispersive medium, the vibration wave propagates with speed dependent on frequency. This property of solid materials causes an adverse effect for localization of vibrational events. The cause behind such phenomenon is that the propagating wave envelope changes its phase delay and amplitude in time and space as it travels in dispersive medium. This problem was previously approached by filtering a signal to focus on frequencies of the wave propagating with a similar speed, with improved accuracy of cross-correlation results. However, application of this technique has not been researched for localization of vibrational sources. In this work we take advantage of filtering prior to cross-correlation calculation while using multiple sensors to indicate an approximate location of vibration sources.

Recently, customers' demands for future mobility have increased, such as movement in narrow spaces, increased driving freedom, and ease of parking. The key technology to meet these demands is the four-wheel independent steering system. In this study, we introduce the concept design process for a four-corner steering module and how to prove the design. In addition, we introduce a control method for basic driving modes, such as short U-turn, diagonal driving, crab driving, and zero radius turning. Finally, we propose a special driving mode using the instantaneous rotation center of the 4WS system.

The H-point is a critical part of vehicle design as it is the basis for many engineering dimensions within the vehicle interior. A complete design process includes comparisons of the design to competitive benchmark vehicles. However, the competitive design considerations needed to determine the common standard H-point reference are often unknown. The SAE Human Accommodation and Design Devices (HADD) technical committee recently published a new standard benchmark SgRP procedure [2]. This new standard practice needed to be tested with respect to the accuracy and repeatability for determining the unknown h-point design parameters within industry benchmarking tolerances. In 2019, the SAE HADD committee conducted a study to evaluate the reproducibility of the new procedure. This paper presents detailed results of that study and discusses opportunities for applying the new benchmark practice.

Rising gas prices and increasingly stringent vehicle emissions standards have pushed automakers to increase fuel economy. Mass reduction is the most practical method to increase fuel economy of a vehicle. New materials and CAE technology allow for lightweight automotive components to be designed and manufactured, which outperform traditional component designs. Topology optimization and other design optimization techniques are widely used by designers to create lightweight structural automotive parts. Other design optimization techniques include free-size, gauge, and size optimization. These optimization techniques are typically used in sequence or independently during the design process. Performing various types of design optimization simultaneously is only practical in certain cases, where different parts of the structure have different manufacturing constraints.

The need to reduce weight and cost of battery systems for electric vehicles has led to continued interest in metal-to-plastic substitution and mixed-material designs for battery enclosures. However, the ever-increasing performance requirements of such systems pose a challenge for plastic materials to meet. In an effort to design a cost-effective, lightweight next-generation battery enclosure while meeting the latest requirements, a new thermal runaway test method was developed, and several materials were screened. The objectives of this development project were twofold. The first was to develop a small-scale test method representative of real-world thermal runaway conditions that could be used early in the design process.

A new pass-by noise test method has been introduced, in which engine speeds and loads are reduced (compared to the old test method) to better reflect real world driving behavior. New noise limits apply from 1 July 2016, and tighten by up to 4dB by 2026. The new test method is recognized internationally, and it is anticipated that the limits will also be adopted in most territories around the world. To achieve these tough new pass-by noise requirements, vehicle manufacturers need to address several important aspects of their products. Vehicle performance is critical to the test method, and is controlled by the full load engine torque curve, speed of response to accelerator pedal input, transmission type, overall gear ratios, tire rolling radius, and resistance due to friction and aerodynamic drag. Noise sources (exhaust, intake, powertrain, driveline, tires) and vehicle noise insulation are critical to the noise level radiated to the far-field.

Fuel Cell Electric Vehicles (FCEV) is zero emission vehicles because it produces only water as a byproduct. The other advantages are a long driving range and a quick refueling time compared with the pure electric vehicle. The air compressor supply compressed air to the cathode of fuel cell stack to chemically react with the hydrogen from the compressed hydrogen tank to generate electric power. The centrifugal air compressor can provide oil free clean air and has significantly improved durability/NVH performance compared with competitor's screw type air compressors. It has other advantages such as compact size and high efficiency at the actual vehicle design condition. In this paper we will describe the centrifugal air compressor's NVH improvement process including rotor resonant mode, rotor unbalance, stator's structural noise, and bearing problems.

An EGR system has been significantly used in order to cope with reinforced exhaust gas regulation and enhancement of fuel efficiency. For the well-designed EGR cooler, performance analysis is basically required. Furthermore, boiling prediction of the EGR cooler is especially essential to evaluate durability failure of abnormal operating conditions in DPF. However, due to intrinsic complexity of detailed 3-dimensional heat transfer tubes in the EGR cooler, no precise technique of boiling prediction has been developed. Therefore, this research had been performed in order to fulfill 3 goals: (1) development of 3-dimentional performance prediction technique including boiling occurrence, (2) generation and validation of a new evaluation index for boiling, (3) development of an optimized EGR cooler for suppressing boiling. In order to increase analysis accuracy and reduce analysis efforts at the same time, 3-dimensional single-phase flow analysis was developed.

A Head-Up Display (HUD) is electrical device that provides virtual images in front of driver. Virtual images are consists of various driving information. Because HUD uses optical system there exist image distortions with respect to image height and driver’s eye position. Image warping is image correction method that makes a geometrical change on image to minimize image distortions. In this paper to minimize image distortions, we use optical data driven warping matrix for each image height. But even though we applied data driven warping matrix, image distortions occur due to assemble and manufacturing tolerances when HUD is built. In this paper, we also suggest pre-warping method to minimize image distortions considering tolerances. We simulated 3 compensation functions to get rid of image distortions from the tolerances. By using proposed pre-warping method we could reduce maximum x, y distance by 31.5%, 39% and average distance by 32.2%, 27.9% of distortions.

The powertrain durability test mode often defines the method by reflecting figures such as frequency of use or severity, but in complex systems, durability is difficult to verify in real life conditions under simple conditions. Therefore, in this session, a new analysis method modeled for each driving unit is presented, rather than analyzing time series data in time to extract representative driving pattern from the perspective of the powertrain load reflecting driving situation and driver’s will by applying machine learning technique, and to develop realistic durability test evaluation mode.

Limited fossil fuel resources, air pollution, and global warming all drive strengthening of fuel economy and vehicle emission standards globally. Much R&D continues to be dedicated to improve fuel efficiency of automobiles and to reduce exhaust gasses. These include improvement of engine/driveline performance for higher efficiency, development of alternative energy, and minimization of air resistance through aerodynamic design optimization. OEM weight reduction-focused research has extended into chassis components (steering knuckle, brakes, control arms, etc.) in sequence from body-in-white(BIW). Wheel bearings, one of the core components of a driveline and part of a vehicle’s unsprung mass, are also being required to reduce weight. Conventionally, wheel bearings have achieved “lightweighting” primarily through design optimization methods. They have been highly optimized today using steel based materials.

The influence of early induction stroke direct injection on late-cycle flows was investigated for a lean-burn, high-tumble, gasoline engine. The engine features side-mounted injection and was operated at a moderate load (8.5 bar brake mean effective pressure) and engine speed (2000 revolutions per minute) condition representative of a significant portion of the duty cycle for a hybridized powertrain system. Thermodynamic engine tests were used to evaluate cam phasing, injection schedule, and ignition timing such that an optimal balance of acceptable fuel economy, combustion stability, and engine-out nitrogen oxide (NOx) emissions was achieved. A single cylinder of the 4-cylinder thermodynamic engine was outfitted with an endoscope that enabled direct imaging of the spark discharge and early flame development.

As demand for fuel efficiency rises, an increasing number of automotive companies are replacing their existing metal designs with carbon-fiber-reinforced polymer (CFRP) redesigns. Due to the handling and manufacturing processes associated with CFRP materials, engineers have more design freedom to create complex, light-weight designs, which would be infeasible to manufacture using metal. Additionally, it is likely that by redesigning with CFRP, many steel assemblies can be consolidated to significantly fewer parts, simplifying or potentially eliminating the assembly process. When designing an automotive crossmember using CFRP materials, designers often aim for a two-piece design (top and bottom), while utilizing reinforcement material where needed. The joining of these two pieces is typically accomplished with many mechanical fasteners and adhesives, significantly increasing the part count and the manufacturing complexity.

In this study, the effects of fuel injection on in-cylinder flow under various injection conditions were investigated using particle image velocimetry measurements in a two-cylinder, direct-injection spark-ignition, optically accessible engine with a spray-guided injection system. Various injection timings and pressures were applied to intensify the turbulence of in-cylinder flow. Simple double-injection strategies were used to determine how multiple injections affect in-cylinder flow. The average flow speed, turbulent kinetic energy, and enhancement level were calculated to quantitatively analyze the effects of fuel injection. Fuel injection can supply additional momentum to a cylinder. However, at an early injection timing such as 300° before top dead center, in-cylinder flow development could be disturbed by fuel injection due to piston impingement and interactions between the spray and air.

Fiber-reinforced plastics (FRPs), produced through injection molding, are increasingly preferred over steel in automotive applications due to their lightweight, moldability, and excellent physical properties. However, the expanding use of FRPs presents a critical challenge: deformation stability. The occurrence of warping significantly compromises the initial product quality due to challenges in part mounting and interference with surrounding parts. Consequently, mitigating warpage in FRP-based injection parts is paramount for achieving high-quality parts. In this study, we present a holistic approach to address warpage in injection-molded parts using FRP. We employed a systematic Design of Experiments (DOE) methodology to optimize materials, processes, and equipment, with a focus on reducing warpage, particularly for the exterior part. First, we optimized material using a mixture design in DOE, emphasizing reinforcements favorable for warpage mitigation.

The significance of thermal management performance in electric vehicles (EVs) has grown considerably, leading to increased complexity in thermal systems and a rapid rise in safety and quality-related concerns. The present real-vehicle-based development methods encounter several constraints in their approach when dealing with highly complex systems. Huge number of verification and validation work To overcome these limitations and enhance the thermal system development process, a novel virtual development environment established using the XiLS (X in the Loop Simulation) methodology. This XiLS methodology basically based on real-time coupling between physical thermal system hardware and analytical models for the other systems of vehicle. To control vehicle model and thermal system, various options were realized through hardware, software and model for VCU (Vehicle control unit) and TMS (Thermal management system) control unit.