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Over the past decade, there have been many efforts to generate engine sound inside the cabin either in reducing way or in enhancing way. To reduce the engine noise, the passive way, such as sound absorption or sound insulation, was widely used but it has a limitation on its reduction performance. In recent days, with the development of signal processing technology, ANC (Active Noise Control) is been used to reduce the engine noise inside the cabin. On the other hand, technologies such as ASD (Active Sound Design) and ESG (Engine Sound Generator) have been used to generate the engine sound inside the vehicle. In the last ISNVH, Hyundai Motor Company newly introduced ESEV (Engine Sound by Engine Vibration) technology. This paper describes the ESEV Plus Minus that uses engine vibration to not only enhance the certain engine order components but reduce the other components at the same time. Consequently, this technology would produce a much more diverse engine sound.

In this paper, we propose a vision based lateral control scheme for autonomous lane change system on highways. Three main techniques are proposed, to improve the lane keeping/lane change performance, and to reduce the ripple in the yaw rate on highways. First, we propose a model based lane prediction method to cope with the momentary failure of lane detection. Second, we innovate an approach to steering wheel angle control based on torque overlay for the EPS of the lateral control. Finally, the multi-rate lane-keeping control scheme is proposed to improve the lateral control performance and to reduce the ripple in the yaw rate. The performance of the proposed method was experimentally evaluated via test vehicle

This paper describes the controllability investigation of the vehicle Steer-by-Wire (SbW) system for safety architecture development. In currently used electric steering systems, the safe state will be the intended loss of assist (LOA) for preventing unintended self-steer or inappropriate vehicle lateral control, and the related studies give guidelines for fault-tolerant systems. Regulations regarding steering systems strictly demand the human driver can steer in the LOA condition. e.g., ECE R79. However, in a steer by wire system, there can be no mechanical coupling between the steering wheel and the steering mechanism, the motor-off can be the safe state no longer. Consisting SbW system, Steering Feedback Actuator (SFA), and Road Wheel Actuator (RWA) shall be addressed in different safe states separately. Even though the loss of assist occurs on SFA, RWA can be in the vehicle lateral control state by using the steering angle signal.

Lane keeping assistant system (LKAS) is expected to reduce the driver workload with assisting the driver during driving and is regarded as a promising active safety system. For the proposed LKAS which requires cooperative driving between driver and the assistance system, a Model Based Predictive Controller (MBPC) is proposed to minimize the effect of system overshoot caused by the time delay from the vision-based lane detection system. In order to validate the proposed LKAS controller, a HIL (Hardware In the Loop) simulator is built using steering mechanism, single camera, torque motor, sensors, etc. The performance of the proposed system is demonstrated in various roadways.

At present, the assembling order of COWL is decided according to the design of the Vehicle’s A pillar outer. Therefore when the factory layout changes, extensive costs are needed according to the changes of the A pillar outer design. Thus, this study was carried out to develop a new COWL structure that is able to determine the layout of the factory without changing the design of the A pillar outer. In addition, by adjusting the DFSS tool to COWL, the direction of the material and thickness of COWL was studied to optimize the dynamic stiffness of the body structure and pedestrian protection performance. Based on this study, the optimization of the OPEN COWL is presented.

Transient control for EV/HEV mode change takes an important role in the system of the parallel HEV, which consists of internal combustion engine (ICE), electric motor (EM), integrated starter & generator (ISG), battery, automatic transmission and clutch (that replaces the torque converter), not only ICE/EM control but also clutch engagement control are the key of it. To improve the mode change performance, this study proposes clutch slip control methods. Method 1. focuses on the open loop clutch pressure control so as to adjust target clutch transfer torque. The main idea of Method 2. is to control the clutch pressure in order to achieve the desired speed difference(Method 2-1) from each side of clutch when motor speed is faster than engine idle speed and keep target engine speed(Method 2-2) when motor speed is slower than engine idle speed. This paper defines control sequence which is scheduling the behavior of powertrain components as well.

Wear of glass fiber reinforced polyamide composites for C-EPS (Column-type Electric Power Steering) worm gear is studied. Main focus of this work is given to moisture absorption of the composites and its effect on wear characteristics. Worm gears in 3 different types are manufactured by modifying the injection design using glass fibers and polyamide (PA12). Mechanical properties of the gears, such as hardness and strength, are evaluated first in terms of the orientation of glass fibers in the composite and then tribological properties are examined. The friction and wear of the worm gear was measured by a specially designed friction tester for worm gears, which measures amount of wear and backlash. Results indicate that the worm gear manufactured by the upper injection design shows the lowest backlash increase compared to the other two cases. Amount of backlash is also decreased by using upper injection design in a wide range operation condition.

The purpose of this paper is to identify and reduce the suspension rattle noise. First, the characteristics of the rattle noise are analyzed experimentally in the time and frequency domain. It was found that the rattle noise and vibration at shock absorber mounting point are strongly correlated. Second, the sensitivity analysis of design parameters is performed using a half car model in ADAMS. The result of the simulation model is verified by comparison with test. Finally, the influence of design parameters for the rattle noise is investigated. The study shows that the shock absorber mounting bushing is the most sensitive parameter to affect the suspension rattle noise. This paper shows how the suspension rattle noise can be improved.

A new control algorithm of a wedge brake system has been developed. The proposed control algorithm is based on the position control and current control of electronic wedge brake(EWB). The EWB control system in rear wheel has both active braking functions like ABS and ESC and convenient function such as EPB. In this paper, development of control algorithm was performed using hybrid brake system(HBS) which consists of hydraulic brake in front wheel and electronic brake in rear wheel. At first, the configuration of EWB system is explained. Next, structure of electronic control in HBS is explained. And then ABS/ESC/EPB control algorithms are shown. ABS control algorithm has wheel slip calculation, wheel error calculation, wheel slip control, position control, current control, and duty control. ESC algorithm consists of yaw error calculation, yaw moment control, wheel slip control, position control, current control, and duty control.

In this paper, we investigate a method to calculate the dynamic instability of a disc brake system and propose a criterion of design modification. To estimate dynamic instability, complex eigenvalue analysis is performed for a brake system and the contribution factor of each component to an unstable complex mode is calculated using complex MAC(Modal Assurance Criteria). From the contribution factors, the most influential component is determined so as to decouple the complex mode, and its geometry is modified in view of the strain energy distribution. Evaluation through noise dynamometer tests verifies the reduction of squeal noises, and this is in accordance with the results of complex eigenvalue analysis.

A low pressure exhaust gas recirculation system (LP EGR system) enables the expansion of the EGR operating area than that of the widely used high pressure EGR system. As a result, fuel consumption and emissions can be improved. In order to meet the EU 5 emissions regulations, an exhaust throttle LP EGR system was used. The EU5 vehicles developed using this system have greater merits than other vehicles. However, because the exhaust throttle LP EGR valve is installed adjacent to the after-treatment system, the material of the LP EGR valve itself must be stainless steel in order to withstand the thermal stress, consequently, the cost is increased. Therefore, in order to achieve cost rationalization for EU6 vehicles, an intake throttle LP EGR system is developed and applied to replace the exhaust throttle LP EGR system. In order to apply the intake throttle LP EGR system, the EGR valve is installed in front of the turbo charger compressor.

Studies in the EU and the USA found higher deformation and occupant injuries in frontal crashes when the vehicle was loaded outboard (frontal crashes with a small overlap). Due to that, in 2012 the IIHS began to evaluate the small overlap front crashworthiness in order to solve this problem.A set of small overlap tests were carried out at IDIADA’s (Institute of Applied Automotive Research ) passive safety laboratory and the importance of identifying the forces applied in each structural element involved in small overlap crash were determined. One of the most important structural elements in the small overlap test is the wheel. Its interaction in a small overlap crash can modify the vehicle interaction at the crash, which at the laboratory the interaction is with a barrier. That interaction has a big influence at the vehicle development and design strategy.

Nowadays vehicle quality is rated for noise and vibration and the interior sound levels have become a major target of automotive companies. Strides have been made in reducing power train, tire and external wind noise over the years. However, HVAC and blower fan flow-induced noise reaches the interior cabin without any sound isolation and can strongly impact customer comfort. In the early stage of vehicle design, it is experimentally difficult to get an estimate of the flow pattern and sound levels. The goal of this study is to develop and validate a numerical noise prediction tool for complete HVAC systems noise, defined as the arrangement of sub-systems such as air intake duct, thermal mixing unit, blower, ducts and outlet vents. This tool can then be used during the development of vehicles to evaluate and optimize the aeroacoustics performances of the system without additional or belated experiments.

A comprehensive investigation was carried out in order to develop the idle sound quality for diesel V6 engine when the engine development process is applied to power-train system, which included new 8-speed automatic transmission for breaking down the noise contribution between the mechanical excitation and the combustion excitation. First of all, the improvement of dynamic characteristic can be achieved during the early stages of the engine development process using experimental modal analysis (EMA) & the robust design of each engine functional system. In addition, the engine structural attenuation (SA) is enhanced such that the radiated combustion noise of the engine can be maintained at a target level even with an increased combustion excitation. It was found that the engine system has better parts and worse parts in frequency range throughout the SA analysis. It is important that weak points in the system should be optimized.

Creep-groan noise is a low frequency noise less than 1000Hz and occurs when the vehicle is moving from stop or slowly stopping while the brake is applied at low brake pressure. The vibration source causing the sound is commonly thought to result from friction force variation in stick-slip phenomenon between friction material and disc. In the past, studies have been mainly focused on stick-slip. However, systematic approach involving chassis components has been recently investigated. In this paper, using a chassis dynamometer creep groan noise was reproduced. Through vibration measurements and modal impact tests, the effects of the vehicle system on creep noise were analyzed.

Press hardenable ultra high strength steel (UHSS) is commonly used for automotive components to meet crash requirements with minimal mass addition to the vehicle. Press hardenable steel (PHS) is capable of forming complex geometries with deep sections since the forming takes place at elevated temperatures up to 900 degrees Celsius (in the Austenitic phase). This forming process is known as hot-stamping. The most commonly used PHS grade is often referred to as PHS1500. After hot-stamping, it is typically required to have a yield strength greater than 950 MPa and a tensile strength greater than 1300 MPa. Most automotive design and material engineers are familiar with PHS, the hot-stamping process, and their capabilities. What is less known is the capability of 3rd Generation advanced high strength steels (AHSS) which are cold stamped, also capable of forming complex geometry, and are now in the process of, or have recently completed, qualification at most automotive manufacturers.

NVH is one of the important factors in automobile development. Brake squeal noise, in particular, is an important indicator of perceived quality of automobile. Squeal noise, one of the most difficult factors in automobile brake development, is noise caused by the complex interaction of friction characteristics, caliper behavior, frequency characteristics and environmental conditions. Therefore, it is not easy to come up with an effective improvement plan in a short time. The purpose of this study is to develop a new evaluation method to improve the squeal noise of the brake caliper system and to select the FIM index, which is the standard for objective numerical analysis. The newly developed Friction Induced Modal Method is an evaluation method that uses an inertia noise dynamometer to control the environment and braking conditions in the same way as the squeal noise conditions generated in the field, and to analyze the NVH characteristics of brake calipers.

This paper describes a fail-operational evaluation of the controllability and comfortability for the safety architecture development of steer-by-wire (SbW) systems. According to the functional safety requirement, it is demanded that Steer-by-Wire systems shall continue to function and not misbehave after a failure by the intended fail tolerant sub-system. Most recently, developing Steer-by-Wire Systems are well advanced in fail-operational design utilizing the redundant systems, principally using Sensor voting or ECU switching functions. The system can sustainably keep the lateral motion of vehicle even though a failure is detected while driving. During such events, the controllability assessment is used to determine the fault-tolerant time interval (FTTI), including failure detection and the safe state transition time.

Although tire forces are important as factors governing the behavior of a vehicle, current chassis control systems have used tire forces indirectly estimated. Hence, this research developed Intelligent Tire System (i-Tire) that can measure tire forces directly. This system used a deform gage and a surface acoustic wave (SAW) sensor, which are capable of passive radio communication. The performance of this developed system was tested with a tire test system (MTS Flat Trac) and a vehicle test.

The development of a high-performance battery and safe and reliable charging methods are two important factors for commercialization of the Electric Vehicles(EV) Hyundai and Ovonic together spent many years in the research on optimum charging method for Ni-MH battery This paper presents in detail the results of intensive experimental analysis, performed by Hyundai in collaboration with Ovonic An on-board Ni-MH battery charger and its controller which are designed to use as a standard home electricity supply are described In addition, a 3 step constant current recharger with the temperature and the battery aging compensator is proposed This has a multi-loop algorithm function to detect its 80% and fully charged state, and carry out equalization charging control The algorithm is focused on safety, reliability, efficiency, charging speed and thermal management (maintaining uniform temperatures within a battery pack) It is also designed to minimize the necessity for user input.