• Journal of Mechanical Science and Technology
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• v.17 no.7
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• pp.958-965
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• 2003

Structural integrity of either a passenger car or a light truck is one of the basic requirements for a full vehicle engineering and development program. The results of the vehicle product performance are measured in terms of ride and handling, durability, noise/vibration/harshness (NVH), crashworthiness and occupant safety. The level of performance of a vehicle directly affects the marketability, profitability and, most importantly, the future of the automobile manufacturer In this study, we used the virtual proving ground (VPG) approach for obtaining the dynamic characteristics. The VPG approach uses a nonlinear dynamic finite element code (LS-DYNA3D) which expands the application boundary outside the classic linear static assumptions. The VPG approach also uses realistic boundary conditions of tire/road surface interactions. To verify the predicted dynamic results, a single lane change test has been performed. The prediction results were compared with the experimental results, and the feasibility of the integrated CAE analysis methodology was verified.

• International Journal of Automotive Technology
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• v.8 no.1
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• pp.49-57
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• 2007

This paper proposes a traction control system (TCS) that uses a sliding mode wheel slip controller and a PID throttle valve controller. In addition, a yaw motion controller (YMC) is also developed to improve lateral stability using a PID rear wheel steering angle controller. The dynamics of a vehicle and characteristics of the controllers are validated using a proposed full-car model. A driver model is also designed to steer the vehicle during maneuvers on a split ${\mu}$ road and double lane change maneuver. The simulation results show that the proposed full-car model is sufficient to predict vehicle responses accurately. The developed TCS provides improved acceleration performances on uniform slippery roads and split ${\mu}$ roads. When the vehicle is cornering and accelerating with the brake or engine TCS, understeer occurs. An integrated TCS eliminates these problems. The YMC with the integrated TCS improved the lateral stability and controllability of the vehicle.

• Transactions of the Korean Society of Automotive Engineers
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• v.13 no.6
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• pp.135-141
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• 2005

Currently many safety assessment tests are conducted by crashing a vehicle against a rigid or deformable barrier. It is quite rational to evaluate crash performance of a vehicle in a barrier test in terms of vehicle stiffness and strength. However, there has been a lot of debate on whether barrier testing is a duplicate of real world crash collisions. One of the issues is car to car compatability. There are two essential subjects in compatability. One is partner-protection when crashing into another vehicle and the other is self-protection when struck by another vehicle. When considering a car to car frontal crash between a mini car and a large heavy car, it is necessary to evaluate human body stiffness of each vehicle. In this study, in order to evaluate the compatability of cars in car-to-car crashes, four tests were conducted. Test speed of each car is 48.3km/h, and the overlap of the mini and large car is $40\%$, and the overlap of the small cars is $100\%$. In all tests, only a drive dummy is used. The test results of the car to car crash test show that vehicle safety standard of mini car is not satisfied compared with large heavy car and HIC value of mini car is higher than large car. In this case observed that the relatively lower stiffness and weight of the mini car resulted in absorbing a large share of the total input energy of the system when crashed into the large heavy car.

• Transactions of the Korean Society of Automotive Engineers
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• v.15 no.5
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• pp.174-179
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• 2007

The transient brake time or distance is one of very important factors to guess the vehicle speed to inspect an automobile accident. But, it is usual that the vehicle speed is estimated by using only skid mark without considering the transient brake distance. Deceleration and the friction coefficients of tire and road surface play an important role in calculating the brake distance. In this paper, a scheme is presented to estimate more accurate automobile speed. The scheme contains the effect of the transient brake distance on the speed. Experiment was carried out on the asphalt, unpacked road to get relationships between the speeds and the skid mark distances, and to get the transient brake time. The experimental results were utilized to construct the equation to approximate more realistic vehicle speeds.

• Journal of Auto-vehicle Safety Association
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• v.11 no.1
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• pp.7-16
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• 2019

There are trying to reduce damage from automobile accident in many countries. In many automobile companies, there have been active study on development of ADAS (Advanced Driver Assistance Systems) for commercialization, in order to reduce damage from automobile accident. ADAS is the system providing convenience and safeness for drivers. Generally, ADAS is composed of ACC (Adaptive Cruise Control), LKAS (Lane Keeping Assist System), and AEB (Autonomous Emergency Braking). AEB of the ADAS, it is an autonomous emergency braking system and it senses potential collide and avoids or degrades it. Therefore AEB plays a significant role in reducing automobile accident rate. However, AEB safety evaluation method is not established not yet. For this reason, this study suggests safety evaluation scenarios with adding cut-in, sensor malfunctioning scenario that scenario domestic street conditions considered as well as original standard AEB scenario of Euro NCAP for establishment of safety evaluation method of AEB. And verifying validity of suggested scenario by comparing the calculated values of the theoretical formulas presented in the previous study with results of the actual vehicle test.

• Transactions of the Korean Society of Automotive Engineers
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• v.21 no.6
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• pp.58-63
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• 2013

It is very difficult to evaluate the impact speed, who caused the accident and what the injury risk of the vehicle occupants was from the outcome of the accident. That's the main reason why there are so many insurance fraud related to vehicle accident. In this study, a vehicle crash accident suspected to an insurance fraud had been reconstructed to evaluate crash speed and the relationship between the crash accident and passenger injury risk. To do this, the scene was reconstructed based on accident investigation report and three vehicle crash tests were done at 27kph, 37kph and 70kph. The crash speed of 27kph and 37kph were chosen based on the damaged vehicle and 70kph was chosen based on the driver's statement. Based on the damage of vehicle and dummy injury measure, impact speed is estimated around 20 to 30kph and the dummy measures show that the passengers are not seems to be severely injured in this speed range.

• Transactions of the Korean Society of Automotive Engineers
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• v.4 no.5
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• pp.109-118
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• 1996

An analysis of handling characteristics of a vehicle is performed for step and pulse steering input, which may be very useful in suspension design stage. Many developed computer programs for vehicle dynamics require test data of compliance effects for proto type car. Therefore, these programs are not suitable for automobile development stage. Using the raw design data of suspension and steering system, we analyze the vehicle behavior for step and pulse steering input with commercial multibody dynamics program, ADAMS. Simulated results are in good agreement with vehicle test results. Vehicle handling characteristics parameters which are very useful in automobile suspension design are evaluated from the analysis.

• Journal of Auto-vehicle Safety Association
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• v.9 no.4
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• pp.20-25
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• 2017

Dynamo based vehicle inspection device is end of line device for automobile industry. The device is utilized as implementing vehicle functionality inspection such as brake force, cruise control, kick-down acceleration, CAN inspection. As dynamo based inspection device is broadly adopted in automobile industry, the dynamic study is required to verify the vehicle test equipment reliability. This research recommends appropriate dynamic brake force inspection procedure and theoretical background for developed equipment. Dynamic characteristic of brake force implementation to roller is simplified. With simplified characteristics, the indirect brake force measurement strategy is developed and adopted. Comparison of each brake force result, the appropriate brake force inspection criterion is given.

• Transactions of the Korean Society of Automotive Engineers
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• v.25 no.1
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• pp.51-59
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• 2017

In 2014, there were approximately 4,762 fatalities on Korean roads. The fatality rate has decreased by 6.5 %, as compared to that of the previous year. The pedestrian-vehicle fatalities (1,795) have also decreased by 6 % over the previous year. However, the percentage of the pedestrian fatalities has increased from 37.9 % to 38.7 % during the same period. This is why further research is required, even though the KNCAP pedestrian safety assessment and KMVSS for pedestrian protection currently exist. This paper studied the Upper Legform to Bonnet Leading Edge Test at the front of the vehicles, which has not been introduced yet in Korea. The test method and procedure of the new BLE test in the Euro NCAP test protocol have been reviewed, and the physical tests on SUV and sedan with different bonnet leading edge heights have also been conducted and reviewed. In addition, the test results and characteristics have been analyzed via comparison with the former BLE test and each vehicle type.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.468-471
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• 2005

The Air Quality Sensor(AQS), located near the fresh air inlet, serves to reduce the amount of pollution entering the vehicle cabin through the HVAC(heating, ventilating, and air conditioning) system by sending a signal to close the fresh air inlet door/ventilation flap when the vehicle enters a high pollution area. One chip sensor module which include above two sensing elements, humidity sensor and bad odor sensor was developed for AQS (air quality sensor) in automobile. With this sensor module, PIC microcontroller was designed with back propagation neural network to reduce detecting error when the motor vehicles pass through the dense fog area. The signal from neural network was modified to control the inlet of automobile and display the result or alarm the situation. One chip microcontroller, Atmega128L (ATmega Ltd., USA) was used. For the control and display. And our developed system can intelligently detect the bad odor when the motor vehicles pass through the polluted air zone such as cattle farm.