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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.

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)

NVH analysis based on numerical simulations before actual test vehicle is available becomes common process in the automotive industry. Furthermore, the latest work scope is extending even to conceptual study in the very early design stage, beyond traditional numerical simulations simply using 3-D CAD data. In case when reasonable information is provided at this very early vehicle development stage, a better decision on the design concept would be possible, and subsequent design process can be carried out in more efficient manner. The core of this trend is that it allows us to predict vehicle performance at the conceptual design stage without 3-D CAD data, and then, with this prediction, to suggest meaningful design directions for next stage. From this point of view, FRF-Based Substructuring (FBS) methodology has potential to be used as an appropriate tool for this purpose.

This paper examines the effect of pulse-and-glide (PnG) driving strategies on the fuel efficiency when applied on parallel HEVs. Several PnG strategies are proposed, and these include the electrical, mechanical, and combined PnG strategies. The electrical PnG strategy denotes the hybrid powertrain control tactics in which the battery is charged or discharged according to the power demanded while maintaining the constant vehicle speed. On the other hand, the mechanical PnG strategy denotes the powertrain control tactics in which the vehicle accelerates or decelerates according to the power load while minimizing the battery usage. The combined PnG strategy involves both electrical and mechanical strategies to find a balanced point in between them. Here, a tradeoff relationship between the fuel efficiency and the vehicle drivability related to the tracking performance of the desired target speed is revealed.

Today, many automakers are using LED lamp sources in exterior lamps to establish brand awareness and introduce specialized lamp designs. These eye-catching LED lamp source solutions require many control functions as the lamp functions are diversified and advanced, and accordingly the requirements for standardization and optimization of controllers are increasing. In particular, our LED rear combination lamps have a variety of LED loads according to the design of the lamp model, the installation position, and the diagnostic regulations, so that the design complexity and the number of specifications of the controller are increased [4]. In recent years, more and more aesthetic designs and new technologies are used by various automakers to optimize their controllers in cooperation with global partners to optimize costs [1].

In terms of reducing the gear noise of automatic transmission, improvement of heat treatment distortion of the annulus gear is very important, because annulus gear is very sensitive heat treatment due to thin walled ring-like shape. Nitriding is very effective method to meet the both requirements for heat treatment distortion and durability of the annulus gear, as compared with conventional carburizing. However, conventional nitriding has problems to be applied for annulus gear, such as brittleness of compound layer and low adhesion strength between compound layer and matrix. In this research, we developed the high toughness nitriding and greatly improved the problems as mentioned above, by controlling gas pressure and temperature.

In this paper, a reconfigurable object-oriented simulator is proposed to analyze the performance of Bluetooth Voice Communication Package (VCP) for telecom purposes like hands-free vehicular communication. It consists of a graphical user interface (GUI) for research or validation engineers to investigate system specific performance. For example, a research engineer can utilize this GUI to analyze a system performance using different noise reduction filtering techniques in vehicular hands-free applications. Also, a validation engineer can utilize this GUI to evaluate vehicular Bluetooth audio quality for different vehicles at different driving conditions (e.g. speeds, fan levels, etc.). The proposed Bluetooth VCP model consists of modules like Audio Equalization (EQ), Acoustic Echo Canceller (AEC), and Noise Suppression (NS). This dynamic GUI platform provides the scope to add and analyze new proposed filtering techniques.

The software must be verified and optimized from time to time to ensure system performance quality from the development process. Because the later you discover performance issues, the greater the cost of performance improvements, along with the extent to which they are fixed in the source code. In particular, performance problems due to poor system design should be identified and corrected as soon as possible. Also, as development progresses, source code added for new features and modified by bugs can potentially increase system resource usage or worsen responsiveness. Therefore, the development process needs to periodically measure, analyze, and improve system performance. This paper introduces the system-wide performance analyzer and explains how to use it to measure and analyze the performance of the infotainment system for performance management and improvement.

The need for a voice recognition system in the automotive industry is growing day by day. In our current voice recognition system, Hyundai's ‘Blue-Link’ and KIA's ‘UVO’ are developed with Microsoft which is a global software company. The system launched domestic market recently. Since usage of voice recognition system are increasing, research and development of Voice Recognition system also increase very fast. Research is mostly focus on increase recognition rate of speech. However there is no research of interior layout considering voice recognition usability. So in this research, we discover interior design factors for maximizing voice recognition usability.

This paper presents the research related to the self-driving system that has been actively carried out recently. Previous studies have been limited to ensure the path following performance in linear and steady state-alike handling region with small lateral acceleration. However, in the high speed driving, the vehicle cornering response is extended to nonlinear region where tire grips are saturated. This requires a technology to create the driving path for minimum time maneuvering while grasping the tire grip limits of the vehicle in real time. The entire controller consists of three stages-hierarchy: The target motion is determined in the supervisor phase, and the target force to follow the target behavior is calculated in the upper stage controller. Finally, the lower stage controller calculates the actuator phase control input corresponding to the target force.

Hydroforming process is an emerging manufacturing technology which allows engineers to use continuous closed section without flange for spot weld in a given package envelope. In this research, Hydroforming is applied to a front pillar and a roof side rail for improvement of obstruction angle, body stiffness and roof crush resistance. In addition, the joints of front / center pillar that were integrated into the hydroforming part and structure of package tray were improved. As a result, front pillar width is reduced by 23%, body torsional stiffness is increased by 45% and roof crush resistance is improved by 35%.

48V mild hybrid engine is one of major eco-friendly technology for global CO2 reduction policy. The 48V mild hybrid engine enables to operate torque boost, recuperation and ISG status by MHSG(Mild Hybrid Starter and Generator). The FEAD(Front End Auxiliary Drive) system is a very important role to transfer MHSG power to crankshaft at the mild hybrid engine. The conventional FEAD configuration is relatively simple because it transfers power from crankshaft to auxiliary drive components in one direction. But the FEAD configuration of 48V mild hybrid engine is not simple due to bidirectional power transmission between crankshaft and MHSG. For instance, in case of torque boost mode, the tight side of auxiliary belt is entry span of MHSG. On the contrary, the tight side of auxiliary belt is exit span of MHSG at recuperation mode.

This paper focuses on the optimization of the cross-section of a panel type impact door beam. The key parameters of the cross-section of the beam were artificially changed by using a geometry morphing tool FCM (Fast Concept Modeler), which is plugged in to CATIA. Then, the metamodel of FE (Finite Element) analysis results was created and optimized using LS-OPT. The ANOVA (Analysis of Variance) analysis of results was carried out to find the factor of weight reduction. Finally, a new cross section concept was proposed to overcome the limitation of old structure. The optimization was carried out for the beam with the final cross-section to have 10 % or more reduction in total weight.

The multi-function drive plate used for a high performance engine was developed by optimizing its structure, material and design features. To do so, the investigation of the load characteristics was done in order to increase FEA reliability. DFSS was utilized for optimizing the design features and defining the effect of geometric parameters on the durability. The durability of the optimized drive plate was verified by comparing the FEA and test results with other drive plates which were already verified. Finally, the real powertrain test was done to confirm its durability for a high performance engine.

Recently, as part of the effort to enhance fuel efficiency and reduce costs for eco-friendly vehicles, the R-gearless system has been implemented in the TMED (P)HEV system. Due to the removal of the reverse gear, a distinct backward driving method needs to be developed, allowing the Electronic Motor (e-Motor) system to facilitate backward movement in the TMED (P)HEV system. However, the capability of backward driving with the e-Motor is limited because of partial failure in the high-voltage system of an R-gearless system. Thus, we demonstrate that it is possible to improve backward driving problems by applying a new fail-safe strategy. In the event of a high-voltage battery system failure, backward driving can be achieved using the e-Motor with constant voltage control by the Hybrid Starter Generator (HSG), as proposed in this study.

Broadband active noise control algorithms require high-performance so multi-channel control to ensure high performance, which results in very high computational power and expensive DSP. When the control filter update part need a huge computational power of the algorithm is separated and calculated by the server, it is possible to reduce cost by using a low-cost DSP in a local vehicle, and a performance improvement algorithm requiring a high computational power can be applied to the server. In order to achieve the above goal, this study analyzed the maximum delay time when communication speed is low and studied response measures to ensure data integrity at the receiving location considering situations where communication speed delay and data errors occur.

The reduction of intake noise is a very important factor in controlling the interior noise levels of vehicles, particularly at low and major engine operating speeds. A vehicle intake system generally consists of air cleaner box, hose, duct, and filter element. Also, resonators and porous duct are included, being used to reduce intake noise. For more accurate estimation of the transmission loss (TL), it seems important to develop a CAE model that accurately describes this system. In this paper, simple methods, which can consider the effects of filter element and vibro-acoustic coupling, are suggested which could remarkably improve estimation accuracy of the TL. The filter element is assumed as equivalent semi-rigid porous materials characterized by the flow resistivity defined by the pressure drop, velocity, and thickness.

This paper describes the optimal design process of the steering column system and the supporting system. At the initial concept stage of development process, a design guide is proposed to obtain sufficient stiffness of the steering system while reducing idle vibration sensitivity of the system. Case studies on resonance isolation are summarized, in which separated vibration modes among systems by applying Vibration Mode Map at the initial stage of design process. This study also makes it possible to provide design guideline for optimal dynamic damper system using CAE (computer aided engineering) analysis. The damper FE (finite element) model is added to vehicle model to analyze the relation between the frequency and the sensitivity of steering column system. This analysis methodology enables target performance achievement in early design stage and reduction of damper tuning activity after proto car test stage.

Various optimization schemes have successfully been utilized to design mounting brackets of chassis components, especially suspension systems, in the large commercial vehicle development process. Depending on the design status, different optimization schemes, i.e. size, topology, and shape, are applied. There are two key elements that determine types of optimization schemes used, which are design freedom and available analysis time. First, in a case that the design is already frozen near the mass production, so that only minimal design change and time is allowed, the size optimization is attempted. Second, in the middle of the design process where relatively more room for the change is available, the topology optimization is adequate to carry out, based on the basic CAD model.

The characteristics of vibration in the seat system are presented using the analysis of Finite Element Method (FEM). The Noise, Vibration and Harshness (NVH) performance should be managed from the viewpoint of tactile, acoustic and visual sense. Tactile response is the response of sub-systems, which is induced when the human body contacts steering wheel, footrest and seats. The seat modeling techniques have been developed and correlated with the modal test. The main modes in the seat system were analyzed and these seat modes were used to set the mode map (seat target) at the stage of full vehicle level. The sensitive region on seat mountings was defined through the design sensitivity analysis. Weight down design studies were performed.