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As world-wide container volume increases and very large container ships emerge as a dominant player in the maritime cargo transport market, functional capabilities of container ports need to be greatly enhanced. To address this problem, KAIST is undertaking a project to design a novel container transport system, namely Mobile Harbor. Mobile Harbor refers to a system that can go out to a large container ship anchoring in the open sea, load and unload containers between the container ship and the Mobile Harbor, and transport them to their destinations. Designing Mobile Harbor presents a number of challenges as with many other large-scale engineering projects, especially at the beginning stage of the project.

In the analysis for durability or R&H performance with the full vehicle multibody models, the need for component flexibility is increasing along with demand for more precise full vehicle system. The component elastic deformations are usually expressed by modal superposition from component normal mode analysis with finite element model for reducing model size and simulation time. Although the simulation results of MBD analysis are more accurate according to increasing the number of flexible body and modes, the increasing of flexible components makes worse simulation time and convergence in MBD analysis. Especially, in the MBD analysis including a flexible upper body, in substitution for large number degree of freedom FE model such as trimmed body, it should take a few times longer than the case of rigid upper body This paper proposes the methods of reducing computational cost with adequate mode selections without the loss of simulation accuracy in the flexible MBD.

This study mainly focuses on developing an accurate tracking controller for the self-energizing clutch actuator (SECA) system consisting of a DC motor with an encoder applied on the automated manual transmission (AMT). In the position-based actuation of the SECA, abruptly increasing torque near the clutch kissing point during the clutch engagement process induces control input saturation and jerky response when a conventional feedback controller is applied. The proposed work resolves such issue and significantly increases the control accuracy of the actuator through the development of an effective H-infinity controller. The control performance is shown to be more effective than a simple PID controller via simulation and experiments using an AMT test bench equipped with SECA aided by d-SPACE and Matlab/Simulink.

This paper presents an adaptation method of equivalent factor in equivalent consumption minimization strategy (ECMS) of fuel cell hybrid electric vehicle (FCHEV) using hilly road information. Instantaneous optimization approach such as ECMS is one of real-time controllers. Furthermore, it is widely accepted that ECMS achieves near-optimum results with the selection of the appropriate equivalent factor. However, a lack of hilly road information no longer guarantees near-optimum results as well as charge-sustaining of ECMS under hilly road conditions. In this paper, first, an optimal control problem is formulated to derive ECMS analytical solution based on simplified models. Then, we proposed updating method of equivalent factor based on sensitivity analysis. The proposed method tries to mimic the globally optimal equivalent factor trajectory extracted from dynamic programming solutions.

The assessment of the Transmission Loss (TL) of vehicle components at Low-Mid Frequencies generally raises difficulties associated to the physical mechanisms of the noise transmission through the automotive panel. As far as testing is concerned, it is common in the automotive industry to perform double room TL measurements of component baffled cut-outs, while numerical methods are rather applied when prototype or hardware variants are not available. Indeed, in the context of recent efforts for reduction of vehicle prototypes, the use of simulation is constantly challenged to deliver reliable means of decision during virtual design phase. While the Transfer matrix method is commonly and conveniently used at Mid-High frequencies for the calculation of a trimmed panel, the simulation of energy transfer at low frequencies must take into account modal interactions between the vehicle component and the acoustic environment.

It is known that SEA is a rapid and simple methodology for analyzing complex vibroacoustic systems. However, the SEA principle is not always valid and one has to be careful about the physical conditions at which the SEA principle is acceptable. In this study, the appropriate damping loss factor of the vehicle interior cavity is studied in the viewpoint of the modal overlap factor of the cavity and the decay per mean free path (DMFP) of the cavity. Virtual SEA tests are performed with an FE model combination, which is suggested by a previous study of Stelzer et al. for the simulation of the sound transmission loss (STL) of vehicle panel structure. The FE model combination is consisting of the body in white (BIW), an acoustical-excited hemisphere-shaped exterior cavity, and the interior cavity. It is found that the DMFP of the interior cavity is appropriate between 0.5 ~ 1 dB for applying SEA principle.

This paper focuses on modeling of the heavy-duty vehicle drivetrain with automatic transmission by using dual clutch scheme. The planetary gear set in the automatic transmission is complicated structure and difficult to understand. The advantage of the dual clutch scheme is that it can be used to represent the complex planetary gear set intuitively, which is a great help to understand the gear shifting process. It is also suitable for being used in the controller due to its low order. Some conditions are required to convert the planetary gear set to the dual clutch model. The heavy-duty vehicle driveline can be converted to the dual clutch model due to its heavy engine and vehicle inertia. This paper also proposes system parameter estimation methods to represent the driveline model. The main parameters are lumped inertia, lumped gear efficiency, output shaft compliance and friction coefficient of clutches.

Demand for electrified vehicles is increasing due to increased environmental pollution regulations and interest in highly efficient vehicles. According to these demands, research on electrified vehicles equipped with Dual Clutch Transmission (DCT) has been actively conducted for the purpose of improving energy efficiency of electrified powertrain, maximizing acceleration performance, and increasing maximum speed. However, since DCT requires clutch to clutch shifting, it is difficult to control drive torque and slip speed using two clutch actuators and a power source input. In order to solve this, a study on a multivariable shift controller has been conducted. However, this study chose a heuristic planning method to control the two outputs. However, since the slip speed and drive torque are coupled, it is necessary to tune the reference for every shift scenario, as well as create unnecessary control inputs or degrade shift control performance.

Impact resistance of plastic underbody parts was studied using simulated injection-molded specimen which can be tested according to different types of material used, injection molding variants like position and number of injection molding gates, and features of ribs. Material applied was glass fiber reinforced polyamide which can be used in underbody parts. Test was performed using several combinations of injection molding gates and rib types. From the test result, optimal design guide for plastic underbody parts was determined. Also, new high impact resistant plastic material made of glass fiber reinforced polyamide 66 (PA66) and polyamide 6 (PA6) alloy was developed and the material properties useful for CAE were determined. As a case study, oil pan and muffler housing were designed following the optimal design guide and CAE. And the reliability of the sample muffler housing designed was verified.

Operator training using a weapon in a real-world environment is risky, expensive, time-consuming, and restricted to the given environment. In addition, governments are under intense scrutiny to provide security, yet they must also strive for efficiency and reduce spending. In other words, they must do more with less. Virtual simulation, is usually employed to solve these limitations. As the operator is trained to maximize weapon effectiveness, the effectiveness-focused training can be completed in an economical manner. Unfortunately, the training is completed in limited scenarios without objective levels of training factors for an individual operator to optimize the weapon effectiveness. Thus, the training will not be effective. For overcoming this problem, we suggest a methodology on guiding effectiveness-focused training of the weapon operator through usability assessments, big data, and Virtual and Constructive (VC) simulations.

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.

Fuel sloshing noise is involved with flow motion inside fuel tanks as well as structural characteristics of vehicles. Therefore it is necessary to introduce Fluid-Structure Interaction (FSI) analysis to predict sloshing noise phenomena more accurately. Purposes of this paper are to verify the reliability of the FSI method and suggest new CAE analysis processes to predict fuel sloshing noise. The vibration of floor panels induced by sloshing impact is evaluated through FSI analysis. A series of tests is carried out to validate simulation results. The numerical optimization of parameters is also carried out to reduce computation time. In addition, effects of sloshing noise factors are discussed based on simulation and test results. Lastly, a method to predict fuel sloshing noise by exerting sloshing load on a vehicle is suggested.

The Design For Six Sigma (DFSS) process consists of four phases, identification & definition of opportunity, concept development, design optimization, and design verification. In the phase of concept development, TRIZ (Russian acronym for Theory of Inventive Problem Solving) is useful for creating new ideas from the present ideas, which includes the trimming strategy, the antidote strategy, and the picket fence strategy. In this paper, systems of a vehicle such as Variable Compression Ratio (VCR) engine, windshield wiper blade, and Continuously Variable Valve Actuation (CVVA) of engine, are selected and new concepts for each system are created by applying the previously mentioned three strategies. FMEA (Failure Mode and Effects Analysis), the latter part in the phase of concept development in DFSS, is conducted for newly generated concepts of systems that are mentioned above. As a result of FMEA, it is found that the wind lift of the wiper blade can be a serious problem.

In this study, the preliminary validation method of the steering system is constructed and the objective is to satisfy the target performance in the conceptual design stage for minimizing the problems after the detailed design. The first consideration about steering system is how to extract the reliable steering effort for parking. The tire model commonly used in MBD(Multi-Body Dynamics) has limited ability to represent deformations under heavy loads. Therefore, it is necessary to study adequate tire model to simulate the behavior due to the large deformation and friction between the ground and the tire. The two approaches related with F tire model and mathematical model are used. The second is how to extract each link’s load in the conceptual design stage. Until now, each link’s load could be derived only by actual vehicle test, and a durability analysis was performed using only pre-settled RIG test conditions.

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.

A sliding door is one of the car door systems, which is generally applied to the vans. Compared with swing doors, a sliding door gives comfort to the passengers when they get in or out the car. With an increasing number of the family-scale activities, there followed a huge demand on the vans, which caused growing interests in the convenience technology of the sliding door system. A typical sliding door system has negative effects on the vehicle interior package and the operating effort. Since the door should move backward without touching the car body, the trajectory of the center rail should be a curve. The curve-shaped center rail infiltrates not only the passenger shoulder room, but also the opening flange curve, which results in the interior package loss. Moreover, as the passenger pulls the door outside handle along the normal direction of the door outer skin, the curved rail causes the opening effort loss.

The windshield is an integral part of almost every modern passenger car. Combined with current developments in the automotive industry such as electrification and the integration of lightweight material systems, the reduction of interior noise caused by stochastic and transient wind excitation is deemed to be an increasing challenge for future NVH measures. Active control systems have proven to be a viable alternative compared to traditional passive NVH measures in different areas. However, for windshield actuation there are neither comparative studies nor actually established actuation concepts available to the automotive industry. This paper illustrates a comparative conceptual study on windshield actuation for the active control of wind noise in a passenger car. Making use of an experimental modal analysis of the windshield installed in a medium-sized vehicle, a reduced order numerical simulation model is derived.

In this research, the influence of tire size and shape on sound radiation in the mid-frequency region was studied. First, the relationship between the structural wave propagation characteristics of a tire excited at one point and its sound radiation was identified by using FE and BE analyses. Then, by using that relationship, the effect of modifying a tire's aspect ratio, width and wheel diameter on its sound radiation between 300 Hz and 800 Hz was investigated. Finally, an optimization of the sound radiation was performed by modification of the tire structure and shape. It was found that most of a tire's structural vibration does not contribute to sound radiation. In particular, the effective radiation was found to occur at the frequencies where low wave number components of the longitudinal wave and the flexural wave first appear.

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.

The alternator provides power to vehicle electrical loads with the battery, and its maximum current depends on various factors such as electrical load, engine speed, thermal condition, and other variables. Above all, thermal effects make alternator simulations more complicated. For example statically similar conditions may show different results according to the temperature variation for each alternator operation. This paper proposes a two-stage statistically-based model structure which separates dynamic thermal effects from steady state performance. The method was validated by experiments and shows good predictive performance, suitable for use in test reduction.