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Active Noise Control and Masking Sound on Speech of a Back-Seat Passenger at a Driver’s Seat

KAIST-Yeongseok Kim, Youngjin Park, Daehyuk Son
Hyundai Motors-Jinseok Hong
Published 2018-06-13 by SAE International in United States
Passengers sitting on the back seats of cars while talking on their mobiles can easily experience the invasion of their speech privacy by the driver. Protecting speech privacy can be done by utilizing masking sounds - masking sound may be so loud that it annoys both drivers and speakers. In this research, the feasibility of utilizing active noise control (ANC) which aims to reduce the level of speech at the driver’s seat and, hence, is able to lower the needed level of masking sounds while still protecting the speech privacy is investigated. Speech reception threshold (SRT), which is a subjective measurement method for speech intelligibility, is proceeded for seeing the effect of ANC on speech intelligibility when the masking sound is in use. The SRT measurement result implied that utilizing ANC to reduce the speech level of the back-seat passenger at the driver’s seat is able to lower the needed level of masking sound for keeping the speech privacy.
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Engine Sound Quality Development Using Engine Vibration

KAIST-Youngjin Park
Hyundai Motor Company-Insoo Jung, Dong Chul Lee, Wootai Kim
Published 2018-06-13 by SAE International in United States
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. With traditional development methods by the tuning of existing vehicle systems, it is not possible to achieve the desired order arrangement, and technologies such as ASD and ESG (Engine Sound Generator) have recently been applied to vehicles. However, since ASD reproduces a synthetic sound and ESG creates a desired sound by exciting…
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A Methodology on Guiding Effectiveness-Focused Training of the Weapon Operator Using Big Data and VC Simulations

KAIST-Ojeong Kwon
University of Central Florida-Won Il Jung, Larry Lowe, Luis Rabelo, Gene Lee
Published 2017-09-19 by SAE International in United States
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. Usability assessments will be done to identify human factors affecting weapon’s effectiveness. Usability assessments consist of data-driven and judgment-driven analytics. The first is generated from raw simulation log files to evaluate the participant’s level of skill. The latter is generated from questionnaires, and…
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Compound Lever Based Optimal Configuration Selection of Compound-Split Hybrid Vehicles

KAIST-Toumadher Barhoumi, Hyunjun Kim, Dongsuk Kum
Published 2017-03-28 by SAE International in United States
Finding optimal split hybrid configurations through exhaustive search is almost intractable, mainly due to the huge design space, e.g. 252 compound split configurations using two planetary gear sets (PG). Thus, a systematic exhaustive design methodology is required to find optimal configurations. While most of the prior studies proposed methodologies that assess the performance within the physical design space, i.e. based on the powertrain configurations, this paper proposes a compound lever-based comprehensive design methodology. The (virtual) compound lever is an attractive design tool defined by two design variables, i.e. α and β, that omits the redundancy existing within the physical design space, thus, reduces the computational load. The proposed method explores the entire (virtual) compound lever design space to find optimal compound split configurations with outstanding fuel economy and acceleration performance. First, two performance metrics, i.e. fuel economy and acceleration performance, are assessed within the entire compound lever design space, and optimal compound lever designs, i.e. optimal α and β, are selected. These selected compound lever designs, however, lack the physical parameters (e.g. PGs connections and…
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Wireless Charging Technology and The Future of Electric Transportation

KAIST-In-Soo Suh
  • Book
  • R-444
Published 2015-06-08 by SAE International in United States
Around the world, the major automakers are developing their strategies for conductive and wireless charging technologies, with concerted efforts to establish technical standards on wireless electric vehicle charging, mainly focused on the safety considerations and inter-operability. Wireless Charging Technology and the Future of Electric Transportation covers the current status of wireless power transfer (WPT) technology and its potential applications to the future road and rail transportation systems. Focusing on the applications of WPT technology to electric vehicle charging and the future green transportation field, Wireless Charging Technology and the Future of Electric Transportation was written collaboratively by nine experts in the field, led by Dr. In-Soo Suh, a professor and researcher from the Korean Advanced Institute of Technology (KAIST). This book brings an in-depth analysis of the most important areas of interest in this new area, such as: • Working principles of wireless power transfer technology • Current technology and its projected future impact on electric vehicles • Comparison between conductive and wireless charging of electric vehicles • Introduction to dynamic wireless charging systems •…
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A Study on How to Utilize Hilly Road Information in Equivalent Consumption Minimization Strategy of FCHEVs

KAIST-Jihun Han, Youngjin Park, Dongsuk Kum
Hyundai Motor Co.-Seongpil Ryu
Published 2014-04-01 by SAE International in United States
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. Finally, simulations for various hilly roads are carried out for validation of the proposed adaptation method of equivalent factor. Results show that the proposed method generates similar equivalent factor trajectory with globally optimal equivalent factor trajectory in the specific drive condition. In conclusion, if future vehicle velocity can be assumed…
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Impact of Hilly Road Profile on Optimal Energy Management Strategy for FCHEV with Various Battery Sizes

KAIST-Jihun Han, Youngjin Park, Dongsuk Kum, Youn-sik Park
Hyundai Motor Company-Seongpil Ryu
Published 2013-10-14 by SAE International in United States
This study investigates how hilly road profiles affect the optimal energy management strategy for fuel cell hybrid electric vehicle (FCHEV) with various battery sizes. First, a simplified FCHEV model is developed to describe power and energy flows throughout the powertrain and evaluate hydrogen consumption. Then, an optimal control problem is formulated to find the globally optimal energy management strategy of FCHEV over driving cycles with road elevation profile. In order to solve the optimal energy management problem of the FCHEV, Dynamic Programming, a dynamic optimization method, is used, and their results are analyzed to find out how hilly road conditions affect the optimal energy management strategies. The results show that the optimal energy management with a smaller battery tends to actively prepare (e.g. pre-charge/pre-discharge) for uphill/downhill roads in order not to violate the battery state of charge (SoC) bounds. On the other hand, when the battery is large enough to handle a deep SoC swing due to hilly road profile, the optimal energy management strategy is not significantly affected by various battery sizes. In conclusion,…
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Robust Feedback Tracking Controller Design for Self-Energizing Clutch Actuator of Automated Manual Transmission

KAIST-Jiwon Oh, Seibum Choi
Hyundai Motors-Jinsung Kim
Published 2013-10-14 by SAE International in United States
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.
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Modeling and Control of Single Turbocharger with High Pressure Exhaust Gas Recirculation Diesel Engine

KAIST-Hojin Jung, Hyomin Jin, Seibum Choi
Doosan Infracore-Minseok Ko
Published 2013-10-14 by SAE International in United States
The regulation of NOx emission from a diesel engine is becoming stricter by the environmental agency and furthermore, EGR has been adopted to reduce NOx emission. Air flow control of a diesel engine combined with turbocharger and EGR is complicated because turbocharger and EGR are coupled physically. This paper examines the design of a model based control structure for diesel engine with a turbocharger and EGR. Model based control provides desirable control strategies from the physical analysis of an engine model. Air fraction and exhaust manifold pressure target based control simulation was conducted in this research. Engine is highly nonlinear and susceptible to uncertainties. To overcome this problem, a robust controller was designed by using a sliding mode control method.
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Dynamic Analysis and Experimental Verification of a Clutchless Geared Smart Transmission System for Hybrid Cars

KAIST-Chiwoong Song, Sun Je Kim, Kyung-Soo Kim, Yong-San Yoon
Hyundai Wia-Sang Hun Lee
Published 2013-04-08 by SAE International in United States
Upon the need of a highly efficient transmission system for conventional cars and the hybrid electric vehicle (HEV) purposes, in the paper, clutchless geared transmission system (CGST) by removing the clutch and incorporating a planetary gear system connected to a motor is newly proposed. The dynamic analysis of CGST operations is carried out, using the lever analogy of planetary gear. The state space model and the mathematical model of CGST structure are derived. Through the simulations of CGST operations, input-output tests and gear shifts are performed. To verify the simulation result, reduced size of CGST testbench is developed and experimented.
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