• Proceedings of the KSME Conference
• /
• 2000.04a
• /
• pp.702-707
• /
• 2000

Under the rapid change of a new vehicle model, it is necessary to develop a durability analysis technique using computer simulation. In order to do this. reliable dynamic stress-time history for the vehicle components must be calculated on various road conditions. In this paper, a full vehicle simulation model which is composed of flexible frame and chassis components is proposed and verified its reliability from the comparison with field test data. Finally, dynamic stress-time history on the rear chassis components is predicted with hybrid and modal superposition method.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2012.10a
• /
• pp.613-616
• /
• 2012

A multi body simulation (MBS) model is developed for predicting the impact harshness of the vehicle. Impact harshness is the vehicle performance to evaluate the impulsive vibration behavior during driving over an obstacle of the road. Thus, the approach is simulated on the time domain for considering the transient behavior of the vehicle. The validity of vehicle component modeling of bushes, dampers and structure flexibilities is verified. The simulations are compared with the test results in both of vertical and longitudinal directions. In particular, the vertical vibration of the vehicle is significantly affected by the body flexibility. Through the sensitivity analysis, main factors for the impact harshness performance are investigated.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.9 no.2
• /
• pp.130-136
• /
• 2001

This paper presents an of a brake pressure restriction valve to a motorcycle anti-lock brake system(ABS). In the conventional anti-lock brake system of automobiles, slip ratio as a control variable is actively controlled, which requires wheel speed sensors, ECU, and a pressure modulator. In the ABS valve that has been developed for use in motorcycles, however, the brake pressure that is close to the wheel locking pressure is preset by simple exercises and then the valve just allows to pass the wheel locking pressure and cutoff the remaining pressure. Simulation studies with a single wheel braking dynamics and lumped chassis model show that the pressure restriction valve has basic ABS functions as well as some robustness properties for the uncertain load and road conditions as well as various initial braking speeds. Field tests also show that the pressure restriction valve avoids the wheel locking effectively.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.5 no.6
• /
• pp.148-154
• /
• 1997

The safety problems of buses have been arisen due to the increasing of road traffic. Occupant injuries are always possible in the rollover accident and the frontal impact. Thus the structure of bus should have sufficient strength to protect passengers under accidental loads. ECE(Economic Commission for Europe) regulation No.66 prescribes that the superstructure of the vehicle shall be sufficient strength for passengers' surviving and the residual space shall be preserved in the passenger compartment during and after the standard rollover accident situation. Rollover test and simulation on a large-sized bus was completed according to the regulation. The coordinates of the points on the bus were measured by photogrammetry system. The rollover situation was revived by structural crashes simulation software, PAM-CRASH, and it was checked that the structure still complied with the requirements of residual space during rollover situation. The residual space was preserved during rollover, so it was proved that the structure of the investigated bus had much probability of survival in rollover accidents.

• Journal of Auto-vehicle Safety Association
• /
• v.14 no.4
• /
• pp.60-69
• /
• 2022

Recently, the importance of simulation validation in a virtual environment for autonomous driving system validation is increasing. At the same time, interest in the advancement of the virtual driving environment is also increasing. To develop autonomous driving technology, a simulation environment similar to the real-world environment is needed. For this reason, not only the road model is configured in the virtual driving environment, but also the driving environment configuration that includes the surrounding environments -traffic, object, etc- is necessary. In this article, FMTC, which is a test bed for autonomous vehicles, is implemented in a virtual environment and advanced to form a virtual driving environment similar to that of real FMTC. In addition, the similarity of the virtual driving environment is verified through comparative analysis with the real FMTC.

• 한국HCI학회:학술대회논문집
• /
• 2009.02a
• /
• pp.1233-1238
• /
• 2009

This study's aim was to confirm that pseudoneglect affects visual attention through car laterality, using a driving simulator with either bisection or quadrisection strategies being applied to road usage. On the pencil and paper tests, the left quadrisection and bisection marks deviated significantly to the left. While driving, the car was significantly lateralized to the right of the lane regardless of conditions. However, in terms of relative laterality, the biggest left laterality occurred on roads 1(bisection), while the smallest left laterality occurred on roads 2 (right quadrisection). Thus, the effect of pseudoneglect was demonstrated in both the pencil and paper tests and the driving simulation task. Also, roads 2 and 4, which were driven on the right side of the lane, showed a tendency for drivers to avoid the centerline, as this was the expected cause of right laterality. This study demonstrated that the pseudoneglect phenomenon can occur in a routine driving task.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.44 no.4
• /
• pp.531-544
• /
• 2024

The purpose of this study is to analyze traffic flow characteristics according to the market penetration rate (MPR) of autonomous vehicles (AV) on road sections where bus rapid transit (BRT) is actually operating. Furthermore, the maximum traffic volume was set through estimation of future traffic demand, and traffic flow characteristics were analyzed through traffic simulation for each scenario considering of a combination of BRT introduction and AV's MPR. To test statistical significance, Kruskal-Willis test and Jonckheere-Terpstra test were used to examine the impact of the market penetration rate of Autonomous vehicles on travel time and delay time etc. At the same time, the existence of the order relationship among travel time data according to the market penetration rate of autonomous vehicle was examined. As a result of the analysis, it was founded that the travel time significantly decreased as the MPR of AV increases in both intermittent flow and continuous flow environments. In particular, in the case of continuous flow, the law of increasing returns was satisfied in the effect of increasing travel speed and reducing travel time as the MPR of AV increases. The results of this study are expected to be used as a basic information for design plans for road reconstruction and space utilization after the commercialization of AV in the future.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.7 no.7
• /
• pp.157-166
• /
• 1999

This paper describes the launching characteristics of a passenger car using a Push-Belt type Continuously Variable Transmission(CVT) which equipped a wet type multi-plate clutch asa starting device and a solid flywheel with a torsional damper for a torsional coupling device. To reduce the torsional vibration of the drive-line , some torsional coupling devices were used for the passenger car equipped CVT having the clutch as a starting device especially . In this study, we developed the computer simulation program to investigate the launching characteristics of a passenger car equipped CVT using the mathematical models of this system. For the mathematical models of the vehicle, the CVT, the we type multi-plate clutch and the torsional damper, we obtained the specification and the necessary data through the reverse engineering of those. For the verification of our analysis, we performed the test of prototype car with different throttle positions at road and dynamometer. The launching characteristics of a passenger car considered here an acceleration performance and an ascending performance.

• Journal of Auto-vehicle Safety Association
• /
• v.11 no.4
• /
• pp.39-49
• /
• 2019

Autonomous vehicle is a car which drives itself without any human interaction. SAE provides technical definitions for autonomous and international standards for test evaluation. Accordingly, automobile industry is actively researching development and evaluation of various ADAS (Advanced Driver Assistance Systems), : representative technology of autonomous technology. Recently, ADAS is in the commercialization level such as ACC, LKAS, AEB, and HDA etc. And it also has issues about safety evaluation. The purpose of HDA in ADAS is reduced the driving load on highway. It has a function which can maintain lane keeping and control distance from forward vehicle. This function is evaluated to be useful for accident prevention. Therefore, this paper proposes the safety evaluation scenario of HDA, considering the domestic highway design criteria and the situation that may arise on the actual highway. We compared and analyzed the data acquired through simulation and actual vehicle test. And verified the reliability of the proposed safety evaluation scenario. The verified result is expected safety evaluation of HDA is possible even under the bad condition, which cannot be tested.

• Journal of Electrical Engineering and Technology
• /
• v.8 no.6
• /
• pp.1431-1438
• /
• 2013

A pack-level battery hardware-in-the-loop simulation (B-HILS) platform is implemented. It consists of dynamic vehicle models using PSAT and multiple control interfaces including real-time 3D driving and GPS mode. In real-time 3D driving mode, user can drive a virtual vehicle using actual drive equipment such as steering wheel and accelerator to generate the cycle profile of the battery. In GPS mode, actual road traffic and terrain effects can be simulated using GPS data while the trajectory is displayed on Google map. In the latter part of the paper, several performance tests of an actual lithium-polymer battery pack are carried out utilizing the developed system. All experiments are conducted as parts of actual development process of a commercial battery pack adopting 2nd generation Prius as a target vehicle model. Through the experiments, the low temperature performance and fuel efficiency of the battery are quantitatively investigated in comparison with the original nickel-metal hydride (NiMH) pack of the Prius.