• Proceedings of the KSR Conference
• /
• 2011.05a
• /
• pp.317-325
• /
• 2011

Vehicle model validation for the static vehicle testing has been done by comparison of the simulation results and test results and the parameters of the vehicle model to be used in the simulation have been adjusted to reflect the measured behaviour. The vehicle model fort the simulation should be validated by suitable tests and/or practical experience. The static vehicle test used to validate the vehicle model are the weight measurement, the wheel offloading test, the bogie rotational resistance test and the sway test. Finally, the computer simulation model has been validated and using the validated vehicle model the acceptance of the vehicle safety of the resistance to flange climbing derailment at low speed can be examined.

• Journal of the Korean Operations Research and Management Science Society
• /
• v.26 no.1
• /
• pp.97-108
• /
• 2001

Design and evaluation of AGV-based material handling systems are very complicated due to the randomness and the large number of variables involved Vehicle travel time is a key parameter for designing and evaluating AGV systems. Although loaded travel time is relatively easy to estimate, determination of empty vehicle travel time is difficult due to the inherent randomness of material handling systems. Most previous studies assume that the empty vehicle travel time is the same as the loaded travel time or assume very specific environments. This paper presents new vehicle travel time models for AGV-based material transport systems. The research effort is focused on the estimation of empty vehicle travel time under various vehicle dispatching policies. Simulation experiments are used to verify the proposed travel time models.

• Proceedings of the KSME Conference
• /
• 2001.06b
• /
• pp.565-570
• /
• 2001

Vehicle dynamics control (VDC) system requires more information on driving conditions compared with ABS and/or TCS. In order to develop the VDC system, tire slip angles, vehicle side-slip angle, and vehicle lateral velocity as well as road friction coefficient are needed. Since there are not any cheap and reliable sensors, recent researches on parameter estimation have given rise to a number of parameter estimation techniques. This paper presents new vehicle model to estimate vehicle's yaw rate. This model is improved from the conventional 2 degrees of freedom vehicle model, so-called bicycle model, taking nonlinear effects into account. These nonlinear effects are: (i) tyre nonlinearity; (ii) lateral load transfer during cornering; (iii) variable gear ratio with respect to vehicle velocity. Estimation results are validated with the experimental results.

• Proceedings of the KSR Conference
• /
• 2002.10b
• /
• pp.845-850
• /
• 2002

Maglev is the vehicle which can run in levitated condition by the electro-magnets, and the vehicle can run without any contact condition. The vehicle is devided in two parts such as carbody and bogies, and the bogies are the driving device of the vehicle. There are many equipments in the bogie, and the frame endure many loads occurred in the operation of the vehicle. The bogie frame is designed and manufactured in the view of good safety and maintainability, and the engineers work to accomplish this purpose.

• Proceedings of the KSR Conference
• /
• 2011.10a
• /
• pp.3073-3078
• /
• 2011

Driverless Train Control System has been recently introduced and commercialized in Korea. It is expected that the vehicle with driverless operation system will be used in new lines such as Sinbundang line soon. Therefore it is necessary to change the system operation and conception of the existing train operation system and the necessity of driverless vehicle monitoring system meeting a new paradigm is rising. In order to dispel concerning about safety issues caused by driverless train operation, the importance to establish vehicle error detection, useful fault diagnosis and rapid action plans is higher than ever. For this, efficient and higher level of vehicle supervision & control system should be essentially supported. In this study, remote driverless vehicle monitoring system using by radio communication is suggested to be used for monitoring and controlling important parts of the vehicle and diagnose and take quick actions when vehicles are in trouble at control tower at real time.

• Journal of Auto-vehicle Safety Association
• /
• v.3 no.2
• /
• pp.11-16
• /
• 2011

In recent years, rapid-increasing market share of compact cars and SUVs has brought for both consumer and automaker to pay more attention on crash compatibility between the compact passenger vehicles and the light trucks (i.e., Pickups and SUVs). Vehicle compatibility regarding both self and partner protection in frontal crash of different class vehicles is one of hot issues in vehicle safety. Furthermore, it is expected that the amendment of UNECE-Regulation 94 to implement compatibility issues in couple of coming years. In this study, conceptual design of compatibility compliant frontal vehicle structure which subjects to improve? the distribution of frontal crash loading and structural engagement between vehicles is introduced. The effects of proposed vehicle structure on both possible candidates (i.e. FWRB, FWDB and PDB) for a compatibility evaluation test procedure and car-to-car crash are also investigated.

• International Journal of Automotive Technology
• /
• v.7 no.7
• /
• pp.803-812
• /
• 2006

In order to reduce the negative effects of dynamic coupling among vehicle subsystems and improve the handling performance of vehicle under severe driving conditions, a vehicle chassis control integration approach based on a main-loop and servo-loop structure is proposed. In the main-loop, in order to achieve satisfactory longitudinal, lateral and yaw response, a sliding mode controller is used to calculate the desired longitudinal, lateral forces and yaw moment of the vehicle; and in the servo-loop, a nonlinear optimizing method is adopted to compute the optimal control inputs, i.e. wheel control torques and active steering angles, and thus distributes the forces and moment to four tire/road contact patches. Simulation results indicate that significant improvement in vehicle handling and stability can be expected from the proposed chassis control integration.

• Proceedings of the KIEE Conference
• /
• 2011.07a
• /
• pp.256-257
• /
• 2011

The development for Eco-friendly cars has been expanded as the concern about environmental pollution and a rise in gas prices. The Electric Vehicle(EV) and Plug in Hybrid Electric Vehicle(PHEV) are generally connected on distribution power systems to charge the traction batteries. The growing number of EV/PHEVs could have a effect on distribution power systems and result in overload of power utilities and power quality problems. In order to reduce the adverse effect on distribution power systems, the influence of electric vehicle loads should be evaluated. In this paper, the influence of electric vehicle loads is evaluated by using OpenDSS(Open Source Distribution System Simulator) according to the penetration rate of electric vehicle.

• Transactions of the Korean Society for Noise and Vibration Engineering
• /
• v.17 no.12
• /
• pp.1217-1222
• /
• 2007

With recent advance in automotive noise control engineering reducing major sound sources in the vehicle, customers perceive Buzz, Squeak and Rattle (BSR) as one of important indicators of vehicle quality and durability. As the long-term goal, we expect to establish the integrated design cycle for the reduction of the BSR noise in the early stage of vehicle development. which consist of design, prediction and evaluation procedures. This is possible only with great bulk of experimental data for BSR noise. In this paper, BSR noise is experimentally identified for vehicle doors, which have been traditionally considered as one of main sources of BSR noise. Based on this result, we proposed systematic method for the prevention of BSR noise in the vehicle doors.

• International Journal of Automotive Technology
• /
• v.7 no.2
• /
• pp.187-193
• /
• 2006

When emergency evasion during running is required, a driver sometimes causes a vehicle to drift, that is, a condition in which the rear wheels skid due to rapid steering. Under such conditions, the vehicle enters a very unstable state and often becomes uncontrollable. An unstable state of the vehicle induced by rapid steering was simulated and the effect of differential steering assistance was examined. Results indicate that, in emergency evasion while cornering and during which the vehicle begins to drift, unstable behavior like spins can be avoided by differential steering assistance and both the stability and control of the vehicle is improved remarkably. In addition, reduction of overshoot during spin evasion by the differential steering assistance has been shown to enable the vehicle to return to a state of stability in a short time in emergency evasion during straight-line running. Moreover, the effectiveness of differential steering assistance during emergency evasion was confirmed using a driving simulator.