• Transactions of the Korean Society of Mechanical Engineers A
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• v.30 no.11 s.254
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• pp.1408-1416
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• 2006

A mathematical knee model was constructed using MADYMO. The purpose of this study is to present a more realistic model of the human knee to reproduce human knee motion. Knee ligaments were modeled as line elements and the surrounding muscles were considered as passive restraint elements. A calf-free-drop test was performed to validate the suggested model. A calf was dropped from the rest at about 65 degree flexed posture in the prone position. The motion data were recorded using four video cameras and then three dimensional data were acquired by Kwon3D motion analysis software. The results showed that general shapes of angular quantities were similar in both the experiment and computer simulation. Functional stability of the anterior cruciate ligament was explicitly revealed through this model.

• Journal of Mechanical Science and Technology
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• v.17 no.12
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• pp.1894-1903
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• 2003

It is necessary to have a dummy that describes the anthropometry of a victim with accuracy. This study presents three scaled side impact dummies constructed for the use of MADYMO. They represent five, fifty and ninety-five percentile Korean males ranged from the age of 25 through 39. Thirty-five anthropometric data were used to scale input files required for MADYSCALE. Geometries, inertia, joints and other parameters for dummies were scaled based on the configurations of EuroSID-1. This study proposes the lateral impact response requirements for head, thorax and pelvis of Korean side impact dummies. A lateral drop impact test was conducted for the head at the height of 200 mm. Lateral pendulum impact tests were also carried out for thorax and pelvis at three specific impact velocities. All these test results were obtained from simulation based on MADYMO. All the procedures of the three tests followed the requirement of ISO/TR 9790.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.15 no.5
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• pp.54-61
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• 2016

This paper try to identify the minimum speed of vehicles in collision between pedestrian head and windshield at vehicle-pedestrian accidents. The MADYMO program was used with NF Sonata vehicle and pedestrian in height of 160cm, 170cm, and 180cm. From the simulation results, it was found that the minimum speed of vehicle was different for each pedestrian height : 49km/h for 160cm, 41km/h for 170cm, and 29km/h for 180cm. The results could be used in speed estimating process when there is a collision trace between pedestrian head and windshield at vehicle- pedestrian accident investigation.

• Journal of Korean Society of Transportation
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• v.20 no.2
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• pp.81-92
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• 2002

An automobile crash with a pedestrian generates a trajectory which is crucial to identify the cause of the crash. Previous researches have been carried out for pedestrian movement using simple explicit formulae. The formulae are derived from elementary physics. Therefore, they could not sufficiently include variables of a vehicle and a pedestrian. To overcome such a limitation, a simulation is utilized for the pedestrian behavior in crash environment. A dynamic software called MADYMO is utilized for the simulation. A simulation model is established. The automobile body and a dummy are modeled with rigid bodies, joints and springs. The simulation results are compared with those from explicit formulae. It is found that the explicit formulae did not fit to pedestrian conditions. Simulations are performed for various velocities of automobiles. Results are discussed for the usage of the simulation.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.16 no.1
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• pp.90-100
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• 2017

This paper investigates pedestrian-thrown distance pattern by pedestrian-vehicle collision position by madymo-simulation. The simulation were performed for every 2.5 cm interval between center and edge of bumper for various vehicle speeds and vehicle shapes. As a result, two critical points where thrown distance change rapidly were found. First critical point locate where pedestrian's shoulder do not contact the vehicle. Second point locate where the center of gravity of pedestrian are close to edge of bumper. Between 1st and 2nd critical points, thrown distance decrease rapidly where collision points move to the edge of vehicle. In other cases, the thrown distance does not change rapidly. This result gives more accurate guideline for pedestrian collision in traffic safety.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.5
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• pp.969-975
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• 2002

Visual effects are important cues for providing occupants with virtual reality in a vehicle simulator which imitates real driving. The viewpoint of an occupant is sensitively dependent upon the occupant's posture, therefore, the total human body motion must be considered in a graphic simulator. A real-time simulation is required for the dynamic analysis of complex human body motion. This study attempts to apply a neural network to the motion analysis in various driving situations. A full car of medium-sized vehicles was selected and modeled, and then analyzed using ADAMS in such driving conditions as bump-pass and lane-change for acquiring the accelerations of chassis of the vehicle model. A hybrid III 50%ile adult male dummy model was selected and modeled in an ellipsoid model. Multibody system analysis software, MADYMO, was used in the motion analysis of an occupant model in the seated position under the acceleration field of the vehicle model. Acceleration data of the head were collected as inputs to the viewpoint movement. Based on these data, a back-propagation neural network was composed to perform the real-time analysis of occupant motions under specified driving conditions and validated output of the composed neural network with MADYMO result in arbitrary driving scenario.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.18 no.6
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• pp.251-258
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• 2018

Recently, due to the increase in the traffic volume of vehicle, the collision of the vehicle collision has been increased so that the neck injuries of the passengers has been increased. In order to prevent this, vehicle collision analysis research using computer simulation has been actively carried out in consideration of the design point of car seat. In this study, I used the MADYMO program for analyzing the passenger behavior using a BioRID II dummy, and predicted the neck injuries of passengers according to the change of the backset at the rearward collision of the driving speed of 16km/h. As a result, it was found that the shorter the backset, the shorter the contact start time but the contact completion time was almost the same and the T1 acceleration showed that the acceleration increased with the backset. In addition, the tensile strength increases as the backset increases, and NIC (Neck Injury Criterion) increases as the head speed reaches the headrest.

• Transactions of the Korean Society of Automotive Engineers
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• v.11 no.3
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• pp.145-154
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• 2003

Occupant simulation models have been used to study trends or specific design changes in several typical crash situations. The ATB, Articulated Total Body, was developed and used to predict gross human body responses to vehicle crashes and pilot ejections. Since the ATB source code is open to public, the user can add their own defined modules and functions. The introduction of seat belts into cars significantly decreased the injury risk of passengers in frontal impacts. In this paper, a new seat belt model was developed and implemented into the ATB. For this purpose, a subroutine of the new seat belt was constructed. A force-deflection function was added to replace an existing function to consider energy absorption. The function includes hysteresis effects of the experiment data of the loading and unloading parts of the seat belt load-extension curve. Moreover, this belt model considers a slip between ellipsoid and belt segments. This paper attempted to validate the ATB program which includes the subroutine of new belt models comparing with the real car frontal crash experiments and MADYMO frontal models. The analysis focusses on the human movement and body accelerations.

• Journal of Korean Society of Transportation
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• v.20 no.3
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• pp.105-113
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• 2002

As the number of pedestrian accident increases, the reconstruction of an accident becomes important to find the source of the fault. Generally, accidents are reconstructed by the intuition of experts or primitive physics. A reconstruction method is proposed using sophisticated optimization technology. At first, a dynamic simulation model is established for the accident environment. Occupant analysis for automobile crashworthiness is employed. The situation before an accident is identified by optimization. The impact velocity and the position of the pedestrian are utilized as design variables. The design variables are found by minimizing the difference between the simulation and the real accident. The optimization process is performed by linking an occupant analysis program MADYMO to an optimization program VisualDOC. Since the involved analysis is dynamics and highly nonlinear, response surface method is selected for the optimization process. Problems are solved for various situations.

• Transactions of the Korean Society of Automotive Engineers
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• v.12 no.1
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• pp.145-152
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• 2004

This paper compares seat vibrations of a small passenger car and a SUV. The results also include the comparison of the human body accelerations and the ride values, such as the component ride values, and SEAT values of 12 axis accelerations obtained at the human body and seat track. The ride comfort evaluation is usually carried out by experiments of real cars which are expensive and sometimes may contain errors by passenger's postures. Simulations by computer, on the other hand, enable to solve these problems when the accuracy is proven. This paper, thus, also shows the correlation of human body vibration between experiments and computer simulations. For the computer simulation, korean dummy models are developed from the Hybrid III models by scaling the body data of Hybrid III to those of Korean men and women. From the comparison between the test data and simulation data, a nice correlation in trends was shown.