• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.18 no.6
• /
• pp.202-210
• /
• 2019

This paper evaluated the performance of passenger vehicles with an AEB(Autonomous Emergency Braking) for various pedestrian-vehicle collision situations. The experiment was conducted at a speed of 30-60km/h on a 2017 3,000cc vehicle using a range of collision scenarios. The results showed that the test vehicle stopped before crashing a pedestrian dummy under all scenarios at 30km/h. The test vehicle reduced the speed but crashed the pedestrian dummy in all scenarios at 40-60km/h. From the paired t-test, there was a speed difference from the AEB system at a significant level of 0.05. In addition, the percentage of speed reduction was quite different for each scenario tested. It was concluded that the current AEB system can prevent pedestrian collisions at speed of 30km/h, but cannot prevent collisions with pedestrians at speed of 40-60 km/h.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.18 no.3
• /
• pp.149-155
• /
• 2010

Currently various safety tests are being performed in many countries with growing interest in vehicle safety. However the vehicles which have good safety performance in these tests could not secure the good performance in real car to car accident. So new test protocol using progressive deformable barrier (PDB) was proposed by EEVC in Europe, NHTSA in USA and some vehicle manufacturers, etc. The target of PDB test is to control partner protection in addition to self-protection on the same test. The proposal is to update current ECE R.94 frontal ODB test. So barrier, impact speed, overlap are changed to avoid bottoming-out in the test configuration. In this paper 3 different tests (R.94, EuroNCAP and PDB test) were carried out using current production vehicles with same structure. The results of these tests were compared to understand PDB test. As a result PDB test shows the highest vehicle deceleration and dummy injury because PDB offers a progressive increase in stiffness in depth and height. However vehicle intrusion was affected with rather test velocity than stiffness of deformable barrier. PDB deformation data is used for partner protection assessment using PDB software and it shows that the test vehicle is rather not aggressive.

• Proceedings of the Safety Management and Science Conference
• /
• 2010.11a
• /
• pp.601-607
• /
• 2010

비신호교차로 사고를 대상으로 신호기 운영방법과 차로폭에 따른 고령운전자 교통사고 특성을 파악하기 강화군, 무주군, 원주시, 보령시의 3년간(2007년-2009년) 교통사고 데이터를 사용하여 일반운전자와 고령운전자의 사고를 비교, 분석하였다. 그 결과, 고령운전자 교차로 교통사고는 점멸신호기로 운영되는 교차로사고는 일반운전자보다 다소 높았으며, 정면충돌사고 일반운전자 사고의 8배나가 높게 나타났다. 또한 고령운전자 교차로 교통사고는 차로폭이 6m초과 13m이하의 교차로에서 41.0%가 발생하여 왕복 3-4차로에서의 교차로에서 고령운전자의 교통사고 발생률이 높은 것으로 나타났다. 따라서 고령운전자의 교차로 교통사고 예방을 위해서는 6m초과 13m이하의 도로에 대한 대책이 마련되어야 할 것이며, 점멸신호기로 운영되는 교차로에 대한 점검이 필요하다.

• Journal of Auto-vehicle Safety Association
• /
• v.6 no.2
• /
• pp.5-11
• /
• 2014

Front side member of the front impacted vehicle plays a key role in minimizing the impacting load transferred to the compartment. To perform that required function, axial collapse should be dominant during side member crashing and, prior to designing side member, it is crucial to minimize bending moment occurred at the front end. In this study, for FE model of a SUV front body, front impact analyses were carried to find out bumper stay design which effectively develope axial collapse in the side member. As a previous work, the thickness of side member reinforcement were changed. Next, the inner thickness of bumper stay was increased. Also, the bead shape and location were modified. Final front body model showed much more axial collapsed mode and enhanced crash performance. In addition, a stay of octagon section was adopted and that model exhibited distinctive increase in impact energy absorption.

• 제어로봇시스템학회:학술대회논문집
• /
• 2000.10a
• /
• pp.314-314
• /
• 2000

This study deals with the analysis of the effectiveness of a safer belt in frontal crash. ATB, Articulated Total Body, program is used as a dynamics solver of the occupant model. ATB is a public code, however, the program is somewhat cumbersome to use due to lack of sufficient user interface. A preprocessor and a postprocessor are, therefore, developed for a user friendly graphic interface in Windows environment. Dialog boxes are used for an interface with GEBOD, Generator of Body Data, for human anthropometry and with ADAMS for vehicle dynamics. It is found through three test simulations that simulated results are in good agreement with those obtained by ATB. The effect of the initial slack of safety belt is investigated for frontal crash using the developed program.

• Journal of the Korean Society of Manufacturing Technology Engineers
• /
• v.26 no.2
• /
• pp.205-213
• /
• 2017

In order to improve occupant protection in frontal crash, the IIHS introduced a small overlap frontal crash test in 2012. When the front corner of a car collides with another car or object, such as utility pole the test replicated the sequence of events. Because occupants move simultaneously forward and toward the side of the vehicle this test is challenging for some airbag and safety belt designs. In the small overlap frontal test, a car travels at 64 km/h toward a rigid barrier. A hybrid III dummy is positioned in the driver seat. 25% of the total width of the car strikes the barrier on the driver side. After review of small overlap frontal test protocol and overall rating, six run-throughs were performed according to the original test method.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.25 no.2
• /
• pp.178-188
• /
• 2019

When using a distributed system, it is very important to know the intention of a target ship in order to prevent collisions. The action taken by a certain ship for collision avoidance and the action of the target ship it intends to avoid influence each other. However, it is difficult to establish a collision avoidance plan in consideration of multiple-ship situations for this reason. To solve this problem, a Distributed Stochastic Search Algorithm (DSSA) has been proposed. A DSSA searches for a course that can most reduce cost through repeated information exchange with target ships, and then indicates whether the current course should be maintained or a new course should be chosen according to probability and constraints. However, it has not been proven how the parameters used in DSSA affect collision avoidance actions. Therefore, in this paper, I have investigated the effect of the parameters and weight factors of DSSA. Experiments were conducted by combining parameters (time window, safe domain, detection range) and weight factors for encounters of two ships in head-on, crossing, and overtaking situations. A total of 24,000 experiments were conducted: 8,000 iterations for each situation. As a result, no collision occurred in any experiment conducted using DSSA. Costs have been shown to increase if a ship gives a large weight to its destination, i.e., takes selfish behavior. The more lasting the expected position of the target ship, the smaller the sailing distance and the number of message exchanges. The larger the detection range, the safer the interaction.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.12 no.3
• /
• pp.65-77
• /
• 2013

Recent advanced sensors and communication technologies have been widely applied to advanced safety vehicle (ASV) for reducing traffic accident and injury severity. To apply the advanced safety vehicle technologies, it is important to quantify the safety benefits, which is a fundamental for justifying application. This study proposed a methodology for quantifying the effectiveness of the advanced driver assistant system (ADAS), and applied the methodology to lane departure warning system (LDWS) and automatic emergency braking system (AEBS) which are typical advanced driver assistant systems. When the proposed methodology is applied to 2008-2010 gyeonggi-province crash data, LDWS would reduce about 10~14% of relevant crashes such as head-on, run-off-the road, rollover and fixed-object collisions on the road. In addition, AEBS could potentially prevent about 50% of total rear-end crashes. The outcomes of this study support decision making for developing not only vehicular technology but also relevant safety policies.

• Journal of Auto-vehicle Safety Association
• /
• v.11 no.4
• /
• pp.6-15
• /
• 2019

Since introducing the offset frontal impact test in EuroNCAP in 1997, the vehicle has been constantly changing according to its usage and purpose. As of 2019, many vehicles have been released to the public, which has led to a large structural mass difference between small, medium and large vehicles. Also, the geometry of the front of the vehicle is completely different for each vehicle and tends not to be perfectly aligned at frontal collisions. The difference in mass of each of these vehicles and less performing structures for offset crashes have led to dramatically worse outcome in a car to car offset frontal impact tests. Even though a decade later passenger cars have become much safer due to consumer test programs and regulatory requirements, the aggressiveness and compatibility that can cause damage to the opponent car in the event of car to car collision is not considered in the above-mentioned section, and therefore much improvement is needed. After many years of study to solve this problem, EuroNCAP has developed a new mode MPDB offset front test that considers the aggressiveness and compatibility that can affect the opponent cars that have collided. This paper introduces the development process of aggressiveness and compatibility evaluation method of MPDB in EuroNCAP which will be implemented from 2020. Several impact tests have been conducted at different test conditions to rate the vehicle structure performance only focused on aggressiveness and compatibility of MPDB.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.35 no.1
• /
• pp.187-192
• /
• 2015

In general, design of urban intersections are fundamentally different from rural intersections, but current urban intersection design has been appled to rural standards. This study has suggested the design standard for urban intersection grades based on the existing literature, field investigating and comparative analysis. Moreover, this study analyzes and compares the differences between urban and rural intersections, and intersections have been derived by appropriate design standards after reviewing the domestic and international grades design criteria. Site survey was performed to validate the derived design criteria by analyzing statistically to establish the design standards. Results were produced for the intersection portion grade standards by comparing the number of instructions which produced appropriate slope degree from 2.5% to 3% in normal condition and slope can be extended to 5% in some critical cases. In-situ investigation was performed to validate the produced data where slope was found from 0.0~8.6%. Additional data of accident analysis were also collected for the validation of the suggested data and correlation analysis was performed using the SPSS tool. Data were analyzed statistically using 95% significance level for vehicle-to-vehicle collided, head-on collision accident rates, where accident rates significantly correlated with the grade. Therefore, appropriate grade at the intersection should be designed and applied in order to reduce the number of accidents at the intersection. Finally, appropriate grades for urban intersections are suggested from 1-3% for normal cases and grades could extend up to 5% for unavoidable cases where extra care must be taken when designing.