• International Journal of Automotive Technology
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• v.7 no.3
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• pp.309-314
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• 2006

In this paper, the ride comfort from a computer simulation was compared to the experimental result. For measuring ride comfort of a passenger car, acceleration data was obtained from the floor and seat during highway running with different speeds. The measured acceleration components were multiplied by the proper weighting functions, and then summed together to calculate overall ride values. Testing several passenger cars, the ride comforts were compared. In order to investigate the effect of vibration signals on the steering wheel, an apparatus to measure the vibrations and weighting functions on the steering wheel were designed. The effect of the steering accelerations on the ride comfort were investigated and added for the overall ride comfort. For the computer simulations, Korean dummy models were developed based on the Hybrid III dummy models. For the Korean dummy scaling, the national anthropometric survey of Korean people was used. In order to compare and check the validity of the developed Korean dummy models, dynamic responses were compared to those of Hybrid III dummy models. The computer simulation using the MADYMO software was also compared to the experimental results.

• Transactions of the Korean Society of Automotive Engineers
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• v.25 no.2
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• pp.140-148
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• 2017

Accidents involving wheelchair accessible vehicles have been frequently occurring since the introduction of these vehicles in the Korean market. However, detailed regulations, which are required to ensure the safety of the wheel-chair occupants, are unavailable. In this study, both domestic and international vehicle safety regulations are analyzed in order to select the regulations that are similar to the transportation environment of Korea. Sled tests with an actual wheel-chair accessible vehicle were carried out based on the analyzed regulation requirements, as well as the values of the HIC, belt loads, dummy movements, and wheelchair movements. The test results showed that the movements of the dummy and the wheelchair did not meet the criteria of the regulation due to the improper positioning of the restraint systems.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2006.05a
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• pp.311-312
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• 2006

In this paper, steering systems for mobile robot with permanent magnet wheels are discussed. The mobile robot with permanent magnet wheels can have three different types of steering and driving configurations; two-wheels, three-wheels, four-wheels. By a Two-WD(Wheel Driving) system, driving and steering characteristics are controlled by ratio of each wheel speeds. Three-WD system is steered by a front wheel and driven by rear wheels. Four-WD system has better stability than two wheel system. Usually the permanent magnet wheel has nearly none slip. Thus turning radius of the mobile robot with three-WD and four-WD System will be increased and the steering and driving system will be complicated. To solve this problem, two magnet wheels with two dummy wheels are used in this study. fuming radius of the developed mobile robot is small and the structure of the robot is simple. It is possible to move forward, backward, to turn left and right, and to rotate freely with two-WD. This study proved that two-WD system is very suitable fur the mobile robot with permanent magnet wheels.

• Journal of Auto-vehicle Safety Association
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• v.12 no.1
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• pp.6-14
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• 2020

Personal mobility, which was used exclusively for leisure activities, has recently been used as a means of transportation, and it is expected to increase its role as the next generation transportation. Sales of personal mobility are increasing rapidly, but the problem is that traffic accidents are also increasing. In this study, human body injury caused by various collisions between electric wheel users and road users that occur on bicycle or pedestrian roads mainly used by personal mobility is analyzed through collision analysis and collision risk analysis. In the case of the collision accident for electric wheel, it is analyzed that the road users are more likely to be injured on the pedestrian road than the bicycle road. In addition, the head hit each other or fall and hit the floor caused severe head injury.

• Journal of the Korean Society for Precision Engineering
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• v.32 no.5
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• pp.483-490
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• 2015

This paper presents a proof-of-concept of a wheel-based magnetostrictive energy harvester (EH), which is a vibration-based EH. Coil-wound Galfenol cantilevers with two permanent magnets (PMs) act EH, while rotating wheels provide a forced vibration to EH. Four different cantilevers are designed and simulated for various end deflection. As expected from the simulation, the cantilever end deflection with triple cavity is the most. Three experiments are conducted to characterize the EH: the first with a magnetostrictive actuator, the second with a motor-driven wheel, and the third with the dummy weights. From the first experiment, the power reaches about 50 mV due to the relatively small displacement of the magnetostrictive actuator. From the second experiment, the power reaches about 120 mW. The power from the Galfenol cantilever is estimated to be about 60% of the total power from the wheel-based magnetostrictive EH.

• Journal of Aerospace System Engineering
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• v.14 no.1
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• pp.16-20
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• 2020

The fatigue happening during the road riding of the vehicle and for the moment the aircraft lands on the runway is closely related to the life cycle of the landing gear, the airframe, the vehicle's suspension, etc. The multiple loads acting on the wheel are longitudinal, lateral, vertical, and braking forces. To study the dynamic characteristics and fatigue stiffness of the vehicle, the dynamic fatigue simulator generally has been used to represent the real road vibration in the lab. It can save time and cost. In hardware, the critical factor in the hydraulic fatigue simulator structure is to decouple each axis and to endure several load vibration. In this paper, the inverse kinematic analysis method derives the magnitude of movement of the hydraulic servo actuator by the coupling after rendering the maximum movement displacement in the axial direction at the center of the dummy wheel. The result of the analysis is that the coupling between the axes is weak to reproduce the real road vibrations precisely.

• Transactions of the Korean Society of Automotive Engineers
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• v.12 no.3
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• pp.177-183
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• 2004

The out-of-positioned small female drivers are most likely to be injured during airbag deployment due to their stature and proximity to the steering wheel and airbag module. In order to investigate the injury mechanisms, some experimental studies with Hybrid III 5% female dummy and with female cadavers could be found from the open literatures. However, the given information from those experimental studies is quite limited to the standard conditions and might not be enough to estimate the airbag inflation aggressiveness regarding on the occupant responses and injury. In this study, a finite element analysis has been performed in order to investigate the airbag-induced injuries. A finite element 5% female human model in anatomical details has been developed. The validation results of the model are also introduced in this paper.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2001.04a
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• pp.711-714
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• 2001

As the life cycle of the vehicle become shorter, the method that reduce the development time of new model become more important. In this reason, the development of the simulator that provides similar environment with the actual vehicle road characteristics is increasing. In this paper, the multi-axis simulator is designed and analyzed by kinematic method. The simulator has a function simulating the 3 load elements; vertical, longitudinal, and lateral force respectively and simultaneously. The result of this paper can be used for developing the multi-axis simulator linkage.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2001.04a
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• pp.288-291
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• 2001

Vehicle evaluation is performed on the proving ground, and durability test and dynamic test cost lots of money and time. Doing replace real vehicle experiment with similar experiment environment, it will take us much more useful advantages. Suspension simulator is required the robust and high-reliability and used widely. But it's natural of high-leveled control technique to manage to be fitted fluid system's property and complex that is for the lack of self-damping, nonlinearity, compressibility. In designing and evaluating simulator, it is important to understand the capability of kinematic and static performances. In this paper, an kinematic modeling and analysis has been presented using ADAMS to design that can reproduce longitudinal, lateral, and vertical force.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2001.04a
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• pp.715-718
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• 2001

Test in the development of vehicle consist of driving test and simulation test. The last one has many advantages. It can reduce time and cost during development, can overcome the spacial and environmental limitation, and can provides repeatabilities of similar experiments and various data. In these reason, the simulation test is used more for analysis and development of new vehicle. In this research the result of kinematic analysis on multi-axis simulator is compared with the simulated result using dynamic analysis program, ADAMS, and the maximum stress and strain are analyzed for the safety of link and specifications of optimal design using finite element method.