• Title/Summary/Keyword: Throw distance

Search Result 28, Processing Time 0.031 seconds

A Study on the Relationship between Impact Speed and Throw Distance of Pedestrian by the difference of the frontal shape of SUV vehicles (SUV 차량의 전면 구조 형상에 따른 충돌 속도와 보행자 전도 거리의 상관관계에 관한 연구)

  • Kang, Dae-Min;Ahn, Seung-Mo
    • Journal of the Korean Society of Manufacturing Process Engineers
    • /
    • v.6 no.3
    • /
    • pp.105-111
    • /
    • 2007
  • The type of pedestrian accident can be characterized by vehicular frontal shape and the height of pedestrian. The trajectory of pedestrian after collision by passenger car is different from that by bus due to vehicular frontal shape. The frontal shape of SUV vehicles is dissimilar to passenger car and bus. So, the trajectory and throw distance of pedestrian by SUV vehicles is not the same of passenger car and bus. In this paper, a series of pedestrian kinetic simulation were conducted to inspect the difference in throw distance between SUV vehicle and passenger car and bus by PC-CRASH that is the program for kinetic analysis of articulated body. From the results, if the height of pedestrian is taller than 1.70m, there is no difference in throw distance between SUV vehicle and passenger car, but if the height of pedestrian is about 1.55m throw distance of SUV vehicle is about 4m longer than that of passenger car at each impact speed. The throw distance of pedestrian by Bus is shorter than that of passenger car and SUV at each impact speed.

  • PDF

A Study on the Relationship between Impact Point of Vehicle and Throw Distance of Pedestrian (충격 지점과 보행자 전도 거리의 상관관계에 관한 연구)

  • Kang, Dae-Min;Ahn, Seung-Mo
    • Journal of the Korean Society of Manufacturing Process Engineers
    • /
    • v.6 no.3
    • /
    • pp.71-76
    • /
    • 2007
  • The fatalities of pedestrian account for about 40.0% of all fatalities in Korea 2005. Vehicle-Pedestrian accident generates trajectory of pedestrian. In pedestrian involved accident, the most important data to inspect accident is throw distance of pedestrian. The throw distance of pedestrian can be influenced by many variables. The variables that influence trajectory of pedestrian can be classified into vehicular factors, pedestrian factors, and road factors. Vehicular factors are the frontal shape of vehicle, impact speed of vehicle, the offset of impact point. Many studies have been done about the relation between impact speed and throw distance of pedestrian. But the influence of the offset of impact point was neglected. The influence of the offset of impact point was analyzed by Working Model, and the trajectory of pedestrian, dynamic characteristics of multi-body were analyzed by PC-CRASH, a kinetic analysis program for a traffic accident. Based on the results, the increase of offset reduced the throw distance of pedestrian. However box type vehicle just like bus, the offset of impact point did not influence the throw distance of pedestrian considerably.

  • PDF

Development of Accident Analysis Model in Car to Pedestrian Accident (차 대 보행자 충돌시 사고해석 모델개발)

  • Kang, Dae-Min;Ahn, Seung-Mo;An, Jung-O
    • Transactions of the Korean Society of Automotive Engineers
    • /
    • v.18 no.3
    • /
    • pp.104-109
    • /
    • 2010
  • The fatality of pedestrian accounts for about 21.2% of all fatality at 2007 year in Korea. In car to pedestrian accident it is very important to inspect the throw distance of pedestrian after collision for exact reconstructing of the accident. The variables that influence on the throw distance of pedestrian can be classified into the factors of vehicle and pedestrian, and road condition. It was simulated by PC-CRASH, a kinetic analysis program for a traffic accident in sedan type vehicle and SPSS program was used for regression analysis. From the results, the throw distance of pedestrian increased with the increasing of vehicle velocity, and decreased with the increasing of impact offset. Also it decreased with the increasing of velocity of pedestrian at accident, and throw distance at the road condition of wet was longer than that at dry condition. Finally, the regression model of sedan type vehicle on the throw distance of pedestrian was as follows; $$dist_i=2.39-0.11offset_i+0.59speed_i-545height_i-0.25walk_i+2.78wet_i+{\epsilon}_i$$.

Development of Accident Analysis Model in Car to Pedestrian Accident (차 대 보행자 충돌 시 사고해석 모델 개발)

  • Kang, D.M.;Ahn, S.M.
    • Journal of Power System Engineering
    • /
    • v.13 no.5
    • /
    • pp.76-81
    • /
    • 2009
  • The fatalities of pedestrian account for about 21.2% of all fatalities at 2007 year in Korea. To reconstruct exactly the accident, it is important to calculate the throw distance of pedestrian in car to pedestrian accident. The frontal shape of SUV vehicle is dissimilar to passenger car and bus, so the trajectory and throw distance of pedestrian by SUV vehicle is not the same of passenger car and bus. The influencing on it can be classified into the factors of vehicle and pedestrian, and road factor. It was analyzed by PC-CRASH for simulation, and SPSS s/w was used for regression analysis. From the simulation results, the maximum impact energy of multi-body of pedestrian was occurred to that of torso body at the same time. And the throw distance increased with the increasing of impact velocity, and decreased with the increasing of impact offset. Also it decreased with the increasing of velocity of pedestrian at accident, and the throw distance of wet road was longer than that of dry road. Finally, the regression analysis model of SUV(Nissan Pathfinder type)vehicle in car to pedestrian accident was as follows; $$disti_i=-0.87-0.11offseti_i+0.69speed_i-4.27height_i+0.004walk_i+0.63wet_i+{\epsilon}_i$$.

  • PDF

Effect of Weight Ball Throw Training on Weight Shifting of Lower Body, Head Speed of Club, and Driving Distance of Amateur Golfers

  • Choi, Woo-Jin;Kim, Tack-Hoon;Oh, Dong-Sik
    • Journal of the Korean Society of Physical Medicine
    • /
    • v.12 no.3
    • /
    • pp.111-117
    • /
    • 2017
  • PURPOSE: To determine the effect of weight ball throw training as a preparatory exercise before golf practice for 8 weeks on back muscle strength, weight shifting of lower body, head speed of club, and driving distance of amateur golfers. METHODS: A total of 18 subjects were randomly assigned to the experimental group (n=9) and the control group (n=9), respectively. For the experimental group, Weight ball throw training was provided to the height of waist and shoulder similar to golf swing with the following schedule: 3 kg weight ball throw training from the first week to the 4th week; 5 kg weight ball throw training from the 5th week to the 8th week. Before and after 8 weeks of training, back muscle strength, weight shifting of lower body, head speed of club, and driving distance of subjects in the two groups were measured. RESULTS: The experimental group showed significant differences in rotational back extension torque, weight shifting of lower body, head speed of club, and driving distance during golf swing (p<.05). However, the control group only showed significant difference in driving distance during golf swing (p<.05). Back extension torque, weight shifting of lower body, and head speed of club showed significant differences between the two groups during golf swing (p<.05). CONCLUSION: Weight ball throw training can positively change rotational back muscle strength, weight shifting of lower body, head speed of club, and driving distance of amateur golfers. Therefore, it might be used as an effective warming up exercise for amateur golfers.

Analysis of Pedestrian Throw Distance from Truck Speed and Bumper Height (트럭의 속도 및 범퍼높이가 보행자 전도거리에 미치는 영향 분석)

  • Shim, Jaekwi;Lee, Sangsoo;Baek, Seryong;Choi, Jungwoo
    • The Journal of The Korea Institute of Intelligent Transport Systems
    • /
    • v.16 no.5
    • /
    • pp.85-95
    • /
    • 2017
  • This study aims to identify the throw distance in terms of truck weight, bumper height, and speed in a truck and pedestrian collision, and to propose a model for throw distance estimates. For this purpose, a simulation analysis is performed using the PC-crash program with the following experiment conditions: Truck weight of 5t, 15t, and 25t, Bumper height from 0.3m to 0.6m by 0.1m, and speed from 10km/h to 100km/h by 10 km/h. Experimental results show that the truck speed and bumper height are found to be significant factors for pedestrian throw distance, but truck weight is not a significant factor. Also, a regression model is developed for pedestrian throw distance estimate from the multiple regression analysis. The adjusted $R^2$ value of the model is 93.3%, which is very good explanatory power.

Collision Characteristics of an Adult Bicycle to a Car (성인용 자전거의 승용차량 충돌특성)

  • Kang, Dae-Min;Ahn, Seung-Mo
    • Journal of the Korean Society of Manufacturing Process Engineers
    • /
    • v.11 no.2
    • /
    • pp.92-97
    • /
    • 2012
  • In the present the usage of bicycle has increased steeply due to well-being and convenient way of movement. In car to bicycle accident, the throw distance of bicycle is very important factor for estimating collision situation. In this study, simulations and collision tests in actual car to bicycle were executed for obtaining throw distance of bicycle. The simulations were executed by PC-CRASHTM s/w with vehicle of sedan type. Sand bags were used for the behavior of bicyclist instead of dummy and factors considered were vehicle velocity, the crashed angles and part of bicycle to vehicle, and bicycle was adult type. From the results, the throw distances of tire collision of 00 was longer than that of 450 tire crash, and the throw distances of 900 frame crash were longer than those of 450 frame crash. With based on actual crash tests and simulations, restitution coefficient of between vehicle and bicycle was estimated as 0.1. Finally the increaser vehicle velocity the longer the throw distances of bicycle and the simulation results were relatively good agreement to the results of experiment.

A Study on the Collision Behavior of Fairy Cycle to Vehicle (어린이용 자전거의 차량 충돌거동에 관한 연구)

  • Kang, Dae-Min;Ahn, Seung-Mo
    • Transactions of the Korean Society of Automotive Engineers
    • /
    • v.20 no.1
    • /
    • pp.106-111
    • /
    • 2012
  • Recently the usage of bicycle has increased steeply in Korea owing to traffic culture of well- being. In a car to bicycle accident investigation, the throw distance of bicycle is very important factor for reconstructing of the accident. The variables that influence on the throw distance of bicycle can be classified into the factors of vehicle and bicycle. Simulations and collision tests in actual car to bicycle accident were executed for obtaining throw distance of bicycle. The simulations were done by PC-$CRASH^{TM}$ and for actual crash tests sand bags were used for the behavior of bicyclist instead of dummy. Factors considered were vehicle velocity and the moving angles of bicycle, also the types of bicycle and vehicle were fairy cycle and automobile, respectively. From the results, the throw distances of a head-on tire collision of $0^{\circ}$ direction was longer than that of tire crash test of $45^{\circ}$ direction, and the throw distances of a head -on frame crash test of $90^{\circ}$ direction was longer than that of frame crash test of $45^{\circ}$ direction. In addition restitution coefficient between vehicle and bicycle was estimated as about 0.1 with based on actual crash tests. Finally the increaser vehicle velocity the longer the throw distances of bicycle, and the results of simulation were relatively good agreement to the experimental results.

A Study on the Factors that Influence the Throw Distance of Pedestrian on the Vehicle-Pedestrian Accident (보행자의 층돌 사고에서 보행자 전도거리에 영향을 주는 인자에 관한 연구)

  • Kang, D.M.;Ahn, S.M.
    • Journal of Power System Engineering
    • /
    • v.13 no.2
    • /
    • pp.56-62
    • /
    • 2009
  • The fatalities of pedestrian account for about 40.0% of all fatalities in Korea 2005. Vehicle-Pedestrian accident generates trajectory of pedestrian. In pedestrian involved accident, the most important data to inspect accident is throw distance of pedestrian. The throw distance of pedestrian can be influenced by many variables. But existing studies have been done for simple factors. The variables that influence trajectory of pedestrian can be classified into vehicular factors, pedestrian factors, and road factors. The trajectory of pedestrian, dynamic characteristics of multi-body were analyzed by PC-CRASH, a kinetic analysis program for a traffic accident. PC-CRASH enables an analyst to investigate the effect of many variables. The influence of the offset of impact point was analyzed by Working Model. Based on the results, the variables that influence trajectory of pedestrian were vehicular frontal shape, vehicular impact speed, the offset of impact point, the height of pedestrian, friction coefficients of pedestrian. However the weight of pedestrian did not affect trajectory of pedestrian considerably.

  • PDF

Design Optimization of Nozzle Shape for a Jet Fan (제트송풍기 노즐의 형상최적설계)

  • Seo Seoung-Jin;Kim Kwang-Yong
    • Transactions of the Korean Society of Mechanical Engineers B
    • /
    • v.30 no.8 s.251
    • /
    • pp.715-721
    • /
    • 2006
  • In the present work, nozzle shape of a jet fan is optimized numerically using three-dimensional Reynolds-averaged Navier-Stokes analysis. Standard $k-{\epsilon}$ model is used as a turbulence closure. Response surface method is employed as an optimization technique. The objective function is defined as maximum throw distance. Three geometric variables, i.e., length and angle of nozzle, and interval between two nozzles, are selected as design variables. As the main result of the optimization, the throw distance has been improved effectively.