• 한국소음진동공학회논문집
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• 제19권1호
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• pp.35-41
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• 2009

Through the multibody dynamic simulation, the analysis model of the modalohr freight car of the DMT freight car was developed. By using the developed analysis model, the running dynamic characteristics was inquired through the dynamic analysis about the modalohr freight car. As the running speed and the primary suspension were increased, the lateral and vertical vibration accelerations of the car-body and the bogie were also increased. In case of the lateral vibration acceleration of the car-body, however, review should be considered since it can be influenced by the nonlinear characteristic of the primary suspension. The lateral and vertical vibration of the car-body were generated at the frequency of $2{\sim}3\;Hz$ and $7{\sim}8\;Hz$. And the lateral and vertical vibration of the bogie were generated at the frequency of $25{\sim}35\;Hz$ at the low speed section, $40{\sim}50\;Hz$ at the high speed section.

• 유공압시스템학회논문집
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• 제4권1호
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• pp.13-17
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• 2007

The brake gain adaptive wheel slip controller for a vehicle is designed in this paper. The brake gain from braking pressure to braking torque defined by friction coefficient, friction area and effective friction radius is estimated by the adaptive law based on the wheel slip dynamics. And the wheel slip controller is designed based on the estimated brake gain. The robustness of the designed controller is analyzed using Lyapunov function and the convergence of brake gain is verified. Proposed wheel slip controller is verified via CarSim simulation with two kinds of desired wheel slip ratio.

• 한국산학기술학회논문지
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• 제14권4호
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• pp.1555-1560
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• 2013

칼럼 타입의 전동조향장치(MDPS) 시스템은 차량 안전성과 연료 효율 향상을 보장하기에 승용차에 보편적으로 장착하고 있다. 시스템 해석과 제어기 개발을 위해서는 보통 Mechanical Simulation사에서 제작한 CarSim 프로그램과 매트랩 시뮬링크의 두 프로그램을 이용하여 제어 알고리즘과 차량 모델이 결합되어 하나의 시스템처럼 동시에 동작하도록 시뮬레이션을 수행한다. 매트랩 시뮬링크의 MDPS 제어 시스템과 완전 차량 모델의 동시시뮬레이션 기술개발에 대한 구체적이 방법이 소개된 적이 없기에 본 연구에서 상세히 소개하기로 한다. 본 연구에서는 사인 파형의 조향핸들입력을 이용한 시뮬레이션 결과가 보여 지고 실험결과와 잘 비교되었다. 이러한 동시시뮬레이션 기술은 차량의 핸들링 성능 평가나 CMDPS 평가 수행 및 로직 튜닝을 위해 효과적으로 사용될 수 있다.

• 동력기계공학회지
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• 제10권2호
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• pp.22-28
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• 2006

Computer simulation of the air flow over an automotive vehicle is now becoming a routine process in automotive industry to assess the aerodynamic characteristics of a medium-size vehicle such as $C_d\;and\;C_1$ and aslo to investigate the possibility of improving aerodynamic performance of the vehicle as a preliminary design for the production line. Mainly due to its contribution in saving time and cost in the development of new cars, computer simulation of the air flow over a vehicle is usually done well before a production car is introduced to the market and in gaining more and more attention as powerful computer resources are getting readily available nowadays. To aerodynamically design a car is mainly related with reducing a drag coefficient of car. A well designed car usually has a $C_d$ value in the range of $0.3{\sim}0.4$. It is understandable that automotive industry is rushing to reduce a drag coefficient as reducing even a small fraction of the $C_d$ value can have an enormous overall impact on many areas. Actually, the present research model was able to achieve a $C_d$ value in the range of $0.3{\sim}0.36$ for flow velocities of $60km/h{\sim}100km/h$ by strategically removing the possible factor hazardous to lower $C_d$ value. Prediction of the medium-size vehicle aerodynamics using CFD was performed when an actual car model was in the development stage and three-dimensional modeling was also performed to optimize it as the best model in terms of the best aerodynamic performance.

• 유공압시스템학회논문집
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• 제7권2호
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• pp.7-12
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• 2010

In these days, the researches about hybrid and fuel cell electric vehicles are actively performed due to the environmental contamination and resource exhaust. Specially, the technology of regenerative braking, converting heat energy to electric energy, is one of the most effective technologies to improve fuel economy. This paper developed a regenerative braking control algorithm that is considered vehicle stability. The vehicle has a inline motor at front drive shaft and has a EHB(Electo-hydraulic Brake) system. The control logic and regenerative braking control algorithm are analyzed by MATLAB/Simulink. The vehicle model is carried out by CarSim and the driving simulation is performed by using co-simulation of CarSim and MATLAB/Simulink. From the simulation results, a regenerative braking control algorithm is verified to improve the vehicle stability as well as fuel economy.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2004년도 ICCAS
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• pp.1874-1879
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• 2004

This paper validates new type electric power steering (EPS) system which is driven by a uni-direction rotational motor and two electromagnetic clutches. The assist motor of the new type EPS produces a torque for assisting the steering in only one direction and two electromagnetic clutches transmit the assist torque to the pinion gear in either left or right direction with respect to the steering rotation. In order to evaluate the static and dynamic characteristics of the new type EPS, the EPS has been modeled by using the well known customized software such as MSC.ADAMS and MSC.CarSim. The ADAMS software has been used to investigate the static characteristics of the proposed system. ADAMS, however, can not describe dynamics of a vehicle and perform the simulation under the various road conditions. Thus the dynamic characteristics of the vehicle including the EPS are analyzed very well by using the CarSim software. A sinusoidal steering input command is applied to the propose EPS system in order to evaluate the static characteristics, while the double lane changes are applied to the vehicle with the EPS in order to evaluate the dynamic performance. Through a series of simulations, we can conclude that the propose EPS shows the stable dynamic characteristics when the rotational direction is changed.

• 대한기계학회논문집A
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• 제41권2호
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• pp.111-119
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• 2017

본 논문은 자세 제어 장치(ESC)와 후륜 조향 장치(RWS)를 장착한 통합 섀시 제어기의 성능을 향상시키기 위해 후륜 조향각을 결정하는 방법을 제안한다. 차량을 안정화시키기 위해 필요한 제어 요 모멘트는 자세 제어 장치와 후륜 조향 장치를 이용하여 만들어진다. 각 장치의 타이어 힘을 결정하기 위해 의사역행렬 제어할당 방법을 적용한다. 제어기의 성능을 향상시키기 위해 후륜 조향 장치의 조향각을 결정하는 데에 네 가지 방법을 적용한다. 차량 시뮬레이션 패키지인 CarSim에서 시뮬레이션을 수행하여 제안된 방법들이 통합 섀시 제어기의 성능을 향상시킬 수 있음을 검증한다.

• 한국도로학회논문집
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• 제19권5호
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• pp.97-106
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• 2017

PURPOSES: This study aims to evaluate the effects of vehicle dynamic behaviors on ride quality. METHODS : Simulation and field test were conducted to analyze the behavior of a driving vehicle. The simulation program CarSIM was applied and an INS (Inertial Navigation System) was used for field experiments. A small simulator was developed to simulate vehicle behavior such as roll, pitch, and bounce. The panels evaluated the ride quality in five stages from "very satisfied"to "very dissatisfied."Experiments were conducted on a total of 144 cases of vehicle behavior combinations. RESULTS :In both simulation and field tests, pitch is the largest and yaw the smallest. Especially in the field test, the amount of yaw is very low, about 7% of pitch and 18% of roll. The sensitive and extensive analysis conducted related ride quality with changing the frequency and amplitude. It was found that the most sensitive frequency range is 8 Hz across all amplitudes. Moreover, the combination of the roll and bounce was most sensitive to the ride quality at the low-frequency range. CONCLUSIONS : This result show that the vertical vehicle behavior (bounce) as well as the rotational behavior (roll and pitch) are highly correlated with ride quality. Therefore, it is expected that a more reasonable roughness index can be developed through a combination of vertical and rotational vehicle behavior.

• 대한기계학회논문집A
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• 제38권11호
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• pp.1291-1297
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• 2014

본 논문에서는 자세 제어 장치와 능동 후륜 조향을 이용한 통합 섀시 제어를 제안한다. 제어에 필요한 요 모멘트를 만들어 내기 위해 직접 요 모멘트 제어 방법을 이용한다. 가중 역행렬 기반 제어할당 방법을 이용하여 제어 요 모멘트를 자세 제어 장치의 제동력과 능동 후륜 조향의 조향각으로 분배한다. 가중 역행렬 기반 제어 할당 방법에 가변 가중치를 도입하여 다양한 구동기 조합을 표현하고 차량의 속도를 높이기 위해 시뮬레이션을 이용하여 가변 가중치를 최적화한다. 차량 시뮬레이션 패키지인 CarSim 에서 시뮬레이션을 수행하여 제안된 방법이 차량의 조종안정성과 횡방향 안정성을 향상시킨다는 사실을 검증한다.

• 대한기계학회논문집A
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• 제40권12호
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• pp.997-1003
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• 2016

본 논문은 자세 제어 장치와 능동 후륜 조향장치를 가지는 통합 섀시 제어에서 요 모멘트 분배를 위해 적응 알고리즘을 적용하는 방법을 제안한다. 통합 섀시 제어는 상위제어기와 하위제어기로 구성된다. 상위제어기에서 슬라이딩 모드 제어 이론을 이용하여 차량을 안정화시키는데 필요한 제어 요 모멘트를 계산한다. 하위제어기에서는 제어 요 모멘트를 만들어 내기 위해 자세 제어 장치의 제동 압력과 능동 후륜 조향장치의 조향각을 결정하는 데에 적응 알고리즘을 적용한다. 차량 시뮬레이션 패키지인 CarSim에서 시뮬레이션을 수행하여 제안된 방법의 타당성을 검증한다.