Refine Your Search

Topic

Author

Affiliation

Search Results

Technical Paper

A Study of Design Methodology to Develop Improved Door System of a Vehicle

2019-04-02
2019-01-0616
This research paper is about a systematic design methodology used to develop improved door system of a vehicle. With a variety of engineering analyses, a new structural design was derived and optimized. The previous door system required improvement of the following problems. First, the lower quality of a door system especially causes the performance degradation such as NVH. But it is difficult to have a robust structure because of the limitations of structural design and manufacturing technologies. Second, for a lightweight vehicle, it is necessary to construct a structure for saving weight while ensuring equal performance. Third, a structure for improving the openness and the visibility through the door is required for the convenience. An optimization structure capable of minimizing the door is needed. In order to solve these problems fundamentally, it was needed to design a new structure that considered all of these from the basic level in the following steps. Step1.
Technical Paper

Development of 4-cylinder 2.0L Gasoline Engine Cooling System Using 3-D CAE Analysis

2019-04-02
2019-01-0156
To satisfy the global fuel economy restrictions getting stricter, various advanced cooling concepts, like active flow control strategy, cross-flow and fast warm-up, have been applied to the engine. Recently developed Hyundai’s next generation 4-cylinder 2.0L gasoline engine, also adopts several new cooling subsystems. This paper reviews how 3-D CAE analysis has been extensively used to evaluate cooling performance effectively from concept phase to pre-production phase. In the concept stage, the coolant flow in the water jacket of cylinder head and block was investigated to find out the best one among the proposed concepts and the further improvement of flow was also done by optimizing cylinder head gasket holes. Next, 3-D temperature simulation was conducted to satisfy the development criteria in the prototype stage before making initial test engines.
Technical Paper

Synergies of Cooled External EGR, Water Injection, Miller Valve Events and Cylinder Deactivation for the Improvement of Fuel Economy on a Turbocharged-GDI Engine; Part 1, Engine Simulation

2019-04-02
2019-01-0245
As CO2 legislation tightens, the next generation of turbocharged gasoline engines must meet stricter emissions targets combined with increased fuel efficiency standards. Promising technologies under consideration are: Miller Cycle via late intake valve closing (LIVC), low pressure loop cooled EGR (LPL EGR), port water injection (PWI), and cylinder deactivation (CDA). While these efficiency improving options are well-understood individually, in this study we directly compare them to each other on the same engine at a range of operating conditions and over a range of compression ratios (CR). For this purpose we undertake a comprehensive simulation of the above technology options using a GT-Power model of the engine with a kinetics based knock combustion sub-model to optimize the fuel efficiency, taking into account the total in-cylinder dilution effects, due to internal and external EGR, on the combustion.
Technical Paper

Improvement of Steering Performance using Steering Rack Force Control

2019-04-02
2019-01-1234
In recent years, steering performance has been improved considerably. Yet there are still complaints about steering feel, especially feedback performance on the road. The existing logic is not focused on steering performance. Therefore, it has a limitation in improving the steering performance. In addition, the steering system has friction and inertia due to the operating structure. this is felt to the driver by friction feeling and inertia feeling. As a result, the steering feedback performance deteriorates. In this study, the following steps are developed to develop new logic. First, The analysis of the steering system determines the key factors that affect the steering fell of the driver and defines the ideal steering system. To implement this ideal steering system, a rack-based feedback control is proposed. Secondly, The observer of rack force was designed to estimate the rack force. In general, the rack force estimator is estimated using the driver's torque, assist torque, etc.
Technical Paper

A development of the model based torque feedback control with disturbance observer for electric power steering system

2019-04-02
2019-01-1233
Electric Power Steering (EPS) control algorithm needs to meet both functional requirements and stability, because a driver interacts with the vehicle using steering system. First, it should make natural steering feeling. Second, it should ensure stability against deterioration of hardware. In order to meet these requirements, conventional control algorithms are designed with a stabilizing compensator and an assist torque map which is a one-to-one map between driver torque and assist motor torque. However, It is hard to tune parameters for satisfy both steering feel and stability because these things interact with each other. So, this paper supposes a torque feedback control algorithm to get independence between steering feel and stability. This paper presents a torque feedback control algorithm to improve steering feel and robustness against deterioration of hardware for EPS system.
Technical Paper

Effects of Bore-to-Stroke Ratio on the Efficiency and Knock Characteristics in a Single-cylinder GDI Engine

2019-04-02
2019-01-1138
As global regulations on fuel economy and CO2 emission are getting stringent, development of high-efficiency SI engine is now more urgent than ever before. Along with advanced techniques on friction reduction, automakers endeavor to decrease bore-to-stroke ratio (B/S) to reduce the heat loss and enhance the fuel conversion efficiency. In this study, the effect of B/S was investigated in aspects of efficiency and knock characteristics using a single-cylinder 0.5L LIVC (late intake valve closing) GDI engine. Three B/S ratio (0.68, 0.83 and 1.00) were tested under the same mechanical compression ratio of 12:1. The head tumble ratio was maintained at the same level to solely investigate the effect of geometrical change of B/S. In addition, as the engine was equipped with dual CVVT system, the optimization on valve timings was conducted to fully exploit the potential of each geometry.
Technical Paper

The Development of a NOx Reduction System during the Fuel Cut Period for Gasoline Vehicles

2019-04-02
2019-01-1292
In general, vehicles do not need to make power from engines in deceleration periods. Therefore, fuel cut-off mode can be applied in these periods to improve fuel efficiency. However, during the fuel cut-off periods, a large amount of fresh air flows from the engine into the catalytic converter equipped with the car because there is no combustion. So, the catalytic materials in the converters are changed into oxidized atmosphere. Eventually the efficiency for the NOx purification of catalytic converter rapidly deteriorates and catalytic converters cannot purify the NOx emitted immediately after the fuel cut-off. So, the conditions of fuel-cut off entries have no choice but to be strict for the cars which should meet stringent regulations such as SULEV 30. This strategy is not good for fuel efficiency. In this study, NOx emission process at this period was analyzed microscopically. Additionally, in order to reduce it, new concept of catalyst had been developed.
Technical Paper

Measuring the Displacement of a Vehicle Body with and Optical Measuring System (Motion Captrure).

2019-04-02
2019-01-0393
The 3D measurement of a body displacement on a moving vehicle needs a quite challenging process. Well-known displacement measuring device such as a dial or strain guage can estimate the displacement in very limited areas. An Accelerometer also can estimate body motion but it has an accumulated error and a bias issue for acquisition of exact displacements. However, An optical measuring (Motion Capture) method which use markers and multiple cameras can read 3D coordinators directly and carry out those measurements well. In this paper, first, we determined how to extract a body displacement from global motion. Then we suggested a combining measurement methodology which use a motion capture and an accelerometer simultaneously, but failed to acquire exact displacement. Along this process, we showed an accuracy comparison between a motion capture and an accelerometer to measure a displacement.
Technical Paper

Development of an Automated Seat Dimension Evaluation System

2019-04-02
2019-01-0401
Seat dimension is one of important factors affecting a driver’s seating comfort, fit, and customer satisfaction. In this regard, seat engineers put tremendous efforts to evaluate seat dimensions of a product seat until the dimensions are consistent with the design reference in computer aided design (CAD) model. However, the existing consistency evaluation process is heavily relying on seat engineers’ manual tasks which are highly repetitive, labor intensive, and time demanding. The objective of this study is to develop an automated system that can efficiently, and accurately measure seat dimensions. By using the developed system, the evaluation time for comparing 18 seat dimensions between CAD and scan models has been substantially reduced by less than 1 minute, which is 99% time saving compared to 2 hours in the existing manual process. In addition, the seat dimensions can be more repeatably measured than the manual measurement based on invented algorithms.
Technical Paper

A Development of 1st Class Comfortable Rear Seat.

2019-04-02
2019-01-0400
Arecent analysis of trends in automobile consumption suggests that three Key phrases can be summarized. “UpgradedConsumption Needs.” Demanding higher quality of automobile consumption such as car grade, products and service, and the eye level of customer contact and service is substantially rising. “Pursuingnewness”. With the spread of IT, our inclusive global culture, the new environment, new products and functions with the acceptance of worldly cultures has exponentially expanded. “Expansionof consumer interaction'”. Our consumers tend to interact sensitively with various market data. current data also insists that Interactions between our consumers increase due to the emergence of various media and information. In essence, the improvement of our consumer sentiment commits in explanation that their demand has been increasedand subdivided. Especially in the automobile, the seat is always in touch with passenger's being and interacts seamlessly with the automobiles.
Technical Paper

A Study on Control Logic Design for Power Seat

2019-04-02
2019-01-0466
The large luxury sedan seats have a maximum movement of 22 way, each of which offers wide moving ranges from 30mm to 260mm. Although the mechanism provides a wide range of adjustments to enhance passenger comfort performance, the seat’s operating range is the largest and widest out of all moving parts of the interior components, facing many constraints on its movement in the constrained interior space. In addition, the power seat is operated by a motor, which makes it difficult for users to determine the amount of adjustment, unlike the manual seat adjustment that allows users to decide the adjustment scope according to their power and feeling. IMS, one-touch mode, is also constrained by parameters such as indoor space package, user's lifestyle, etc. during function playback. In this regard, this paper aims to design the seat control logic to achieve the best seat comfort while satisfying each constraint.
Technical Paper

In-Gear Slip Control Strategy of Dry-clutch Systems using a Sliding Mode Control

2019-04-02
2019-01-1305
This paper proposes a clutch control strategy during in-gear driving situations for Dual Clutch Transmissions (DCTs). The clutch is intentionally controlled to make small amount of a slip to identify the torque transfer capacity. The control objective of this phase is to ensure the clutch slip fairly remaining the specified value. To achieve this, the micro-slip controller is designed based on sliding mode control theory. Experimental verifications performed on onboard control system of the DCT equipped vehicle demonstrate that the proposed controller good tracking performance of the desired slip speed.
Technical Paper

Development of Ultra-Stable Cu-SCR Aftertreatment System for Advanced Lean NOx Control

2019-04-02
2019-01-0743
The integration of SCR catalyst into diesel-particulate filter (SDPF) may be one of most viable ways to meet upcoming stringent emission regulations with new test protocols such as Worldwide harmonized Light vehicles Test Cycles (WLTC) and Real Driving Emissions (RDE) requirements. The chabazite-structured SSZ-13-based catalysts enabled the wide implementation of urea-SCR technology for mobile applications due to their robust thermal stability up to 750℃ compared to the thermally unstable ZSM-5-based technologies. However, the thermally stable Cu-SSZ-13 catalyst starts collapsing its active unique structure at 850℃, where the SCR catalyst on SDPF can possibly be exposed during filter regeneration under a drop-to-idle (DTI) condition. Therefore, more durable SCR catalysts that survive under higher temperatures have been strongly desired in automotive industry. Recently, we found Cu-exchanged high silica LTA revealed an excellent hydrothermal stability.
Technical Paper

A Development of the Wirelss Power Transfer Technology for a Sliding Door

2019-04-02
2019-01-0485
The sliding door’s movement is 3-dimensional unlike the conventional door. So the electric power and signal are exchanged via the long ‘Power Cable’. It has a quite complex structure in order to be suitable to connect the vehicle’s body and the sliding door even during it’s moving. As the result, It is more expensive than conventional door’s one and the quality could not be guaranteed easily. In this paper, I have developed new technology which could transfer electric power by ‘wireless transfer’ in order to resolve the problem from using ‘Power cable’. I would propose the proper structure to transfer the electric power at any position of the sliding door without any physical connection. To transfer the electric power which drives the window regulator and the actuators in door, I have applied the ‘inductive coupling’ system.
Technical Paper

Numerical Parametric Study of a Six-stroke Gasoline Compression Ignition (GCI) Engine Combustion

2019-04-02
2019-01-0207
Numerical investigation of engine performance and emissions of a six-stroke gasoline compression ignition (GCI) engine combustion at low load conditions is presented. In order to identify the effects of additional two strokes of the six-stroke engine cycle on the thermal and chemical conditions of charge mixtures, an in-house multi-dimensional CFD code coupled with high fidelity physical sub-models along with the Chemkin library was employed. The combustion and emissions were calculated using a reduced chemical kinetics mechanism for a 14-component gasoline surrogate fuel. Two power strokes per cycle were achieved using multiple injections during compression strokes. Parametric variations of injection strategy viz., individual injection timing for both the power strokes and the split ratio that enable the control of combustion phasing of power strokes were explored.
Technical Paper

Experimental and Numerical Study on Speaker Design of Active Pedestrian Alerting System (APAS) in Hybrid and Pure Electric Vehicles

2018-06-13
2018-01-1550
APAS refers to a low speed sound warning system of electric vehicles, which emits alerting sound only to target pedestrians by sound focusing techniques with array of speakers and object detective camera. In the present study, experimental and numerical investigations are conducted in designing speaker part and array of APAS with consideration of three main performance matrices; HEV/EV warning sound regulations in Europe and U.S., pedestrian awareness, and driver’s noise comfort. The present APAS speaker consists of back enclosure, wave guide and front grill. Each of these components plays an important role for characterizing frequency emphasis and sound directivity. The main impedance frequencies of the speaker are determined by considering warning sound regulations and also by analyzing acoustic frequency response at in/outside of a vehicle.
Technical Paper

Engine Sound Quality Development Using Engine Vibration

2018-06-13
2018-01-1487
Automotive companies are trying to enhance the customer’s impression by improving engine sound quality. The target of this sound quality is to create a brand sound that is preferred by their customers as well as quietness of interior noise. Over the past decade there have been many studies in the field of automotive sound quality. These have included the technologies such as tuning of intake orifice and exhaust orifice, tuning of structure-borne, intake feedback devices, active exhaust valves, ANC (Active Noise Cancellation) and ASD (Active Sound Design). The three elements of the sound that affect the feeling of the customer are known as engine order arrangement, frequency balance, and linearity. Here, the most important thing in sound quality development is the order arrangement.
Technical Paper

Development of Mass Producible ANC System for Broad-Band Road Noise

2018-06-13
2018-01-1561
The mass producible broad-band ANC system for road noise is developed with fully digital control system. For this configuration, installation packages are intensively considered by minimizing size of the controller, simplifying wiring system and implementing virtual microphone techniques. Virtual microphone technique enables error microphone to be installed in remote position of driver’s ear, and therefore, increases installation degree of freedom significantly. To enhance noise control performance with the minimum latency, filter design of FxLMS algorithm is optimized while additional audio compensation techniques are applied to maintain audio performance of amplifier. The present ANC system is equipped to HMC (Hyundai Motor Company) new release of hydrogen driven vehicle, which is introduced in the technology promotion event in Pyeongchang Olympic 2018.
Technical Paper

The Effects of Suspension Component Stiffness on the Road Noise: A Sensitivity Study and Optimization

2018-06-13
2018-01-1510
This paper investigates the sensitivity of stiffness of front and rear suspension systems on the structure-borne road noise inside a vehicle cabin. A flexible multi-body dynamics based approach is used to simulate the structural dynamics of suspension systems including rubber bushings, suspension arms, a subframe and a twist beam. This approach can accurately predict the force transfer to the trimmed body at each suspension mounting point up to a frequency range of 0 to 300 Hz, which is validated against a force measurement test using a suspension test rig. Predicted forces at each mounting point are converted to road noise inside the cabin by multiplying it with experimentally obtained noise transfer functions. All of the suspension components are modeled as flexible bodies using Craig-Bampton component mode synthesis method.
Technical Paper

A Study on the Method to Manage the Weight and Cost of a Vehicle by Adjusting the Parameters of Styling Profile

2018-04-03
2018-01-1025
Since the fuel efficiency of vehicle has become one of the big issues due to environmental pollution problems, many studies have been conducted on various methods such as improving powertrain performance and aerodynamic performance, reducing the weight of the vehicle and so on. There have been many new attempts to reduce weight but mostly about improving material property. In the case of vehicles sharing the same platform, the weight and cost of vehicle are mainly changed by the exterior styling. But, there is no solution to control the exterior styling in terms of the weight and cost of vehicle, yet. The purpose of this study is to find the way to save the weight and cost of vehicle while achieving the various performance and requirements of vehicle (safety, aerodynamics, driver’s visibility and so on) from exterior styling point of view. We focused on the weight difference of the vehicles that shared the platform and were same overall dimensions.
X