• Journal of the Korean Society of Manufacturing Process Engineers
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• v.9 no.6
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• pp.43-50
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• 2010

This study aims to analyze the structural safety by comparing deformation and equivalent stress of door with a stiffener or no stiffener when the door crashes against something in case of overturn. Three types are classified on the basis of the no stiffener model in the vehicle door. One is the type which has a stiffener. Another is the type which has no stiffener and the other is the type which has a hole in the stiffener. These three types are compared with each other by analyzing. This side door of vehicle is the automotive part about the kind of vehicle as Mercedes Benz E-Klasse scaled down as 1/18 times as the real size. The study model of vehicle door is modelled by CATIA program and it is analyzed by ANSYS.

• International Journal of Highway Engineering
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• v.11 no.2
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• pp.45-54
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• 2009

Despite vehicle instability problems caused by gusts of wind on freeways located in mountain or seaside areas, current national highway design standards overlook their detrimental effects, and if higher design speed freeways being proposed now by the government are in operation, the strong effect of the gust of wind becomes a highway alignment design issue. This paper presents the vehicle movements and their resulting safety effects by checking vehicle sliding and overturn based on vehicle dynamic analysis for the case when a gust of wind blows to vehicles negotiating curves on higher speed freeways. In this analysis, vehicle types, curve radii, motorist responsive time to vehicle driving path changes, and vehicle speeds are systematically arranged to get vehicle sliding and overturn values in each different conditions. The results showed that there were little overturn possibilities when wind speed would stay in 50m/sec with higher than 600 meter curve radii. Interestingly it was also found in sliding checks that, although being safe at less than 15.0m/sec wind speed levels, there appeared the need of vehicle travel prohibitions when the wind speed could exceed 25.0m/sec level. The findings in this research is of information in future higher speed freeway designs, and particularly useful when designing freeways passing frequent gust wind areas.

• The Journal of the Convergence on Culture Technology
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• v.5 no.3
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• pp.263-269
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• 2019

In this study, the characteristics and operation of a multi-purpose loader equipped with various sensors such as a sensor capable of measuring the boom length, an angle sensor capable of measuring the tilt of the left and right sides of the boom and the loader, and a load cell capable of measuring the weight during lifting We have implemented a system that displays related data values. The configuration of the system reads the values from the sensors, sends them to the vehicle controller, and transmits the calculated results of the overturn rate and other important information to the display device using the CANOpen protocol. Also, in the calculation of the overturn ratio, the structure of the multi-purpose loader is similar to that of the crane belonging to the heavy equipment, and the crane overturn rate calculation method is used. Through this study, we can observe the condition of the heavy equipment and recognize the emergency situations such as abalone through the display device.

• Transactions of the Korean Society of Automotive Engineers
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• v.12 no.6
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• pp.166-174
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• 2004

In urban area narrow commuter vehicles have attracted interest as a possible solution to reduce traffic congestion and parking problems. However, a narrow vehicle has an increased to overturn during hard cornering when compared to conventional vehicles. This tendency can be reduced by tilting it toward the inside of the turn. Two types of automatic tilting control systems which are Direct Tilt Control(DTC) and Steering Tilt Control(STC) have been developed. In this paper as one of the technique to improve the handling performance for the unusual vehicle the control system which blends both the DTC and the STC system is considered. It uses the merits of both the DTC and the STC system. As a control strategy for combination the switching control method is used. Finally, the fact that the unusual vehicle is safe under an emergency situation such as slippery road surface is proved by computer simulation.

• Journal of the Korean Society of Safety
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• v.30 no.2
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• pp.1-8
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• 2015

Forklift truck is a very convenient transportation vehicle and widely used in industries. However, a lot of overturn accidents occur during operation because of poor understanding on the stability of forklift trucks. The stability of a forklift is defined by the minimum slope of the ramp where a forklift truck overturns. According to the KS BISO 22915-2 code, the stability is determined from the four kinds of stability tests. The equations for the stability of a forklift truck were proposed already in several published literatures and the equations can be used conveniently to estimate the stability and examine the effects of design parameters in forklift trucks. However, because the detail derivation procedure was omitted, it is very difficult to examine the accuracy of the proposed equations and to modify the equations for other types of forklift trucks. In this paper the stability equations were derived again with detail derivations for the four kinds of stability tests. And the effects of acceleration or centrifugal forces were also additionally included in the equations and minor corrections were also made.

• Journal of Advanced Marine Engineering and Technology
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• v.36 no.2
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• pp.250-257
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• 2012

Currently, large vessels and structures are manufactured into set of blocks, then assembled on-site. Large scale ships that weigh thousands of tons are built in a short period by making set of large blocks and assembled on a dock or a land. When a transporter encounters a slope during the process of transporting blocks, the heavy goods loaded on the transporter can be tilted. Further, if the vehicle moves down the slope in this state then it can cause an accident of overturn of loaded goods. The research has been taken into account to calculate the center of gravity of the transporter carrying heavy objects on a leveled surface or the three dimensions. In addition, ZMP (Zero Moment Point) is used to calculate the allowable slope degree that objects are predicted to overturn. Through the simulation, the objects' stability is tested when it is climbing the slope.

• International Journal of Highway Engineering
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• v.13 no.3
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• pp.139-146
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• 2011

Travelling vehicles on roads may slip or overturn due to strong cross wind. This paper presents the path deviation equation and the overturning equation of vehicle, and the process of evaluating the cross wind risk. Case studies for cars and trucks are carried out. It explains the mechanism why the deviation occurs according to the types of vehicles. It shall help to prepare the measures for reducing the risk of travelling vehicles in high wind speeds.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.11
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• pp.5558-5565
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• 2012

Roadside barriers are facility for preventing cars from out of path, and 7 classes of barrier are prescribed in criteria of road grades and speed limit, etc. However, overload and overspeed are increased according to improvement of vehicle performance, and falling over frequently occur in vehicle accident related in barriers. Therefore, enhancement of the existing design criteria of roadside barriers is demanded. In this research, vehicle crash simulation was carried out, and the condition for fracture of roadside barriers and vehicle overturn was evaluated in order to verify the defence performance of the barriers, which are SB5 steel barrier and SB6 concrete barrier adapted mainly to highway.

• Journal of Biosystems Engineering
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• v.38 no.4
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• pp.240-247
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• 2013

Purpose: This study was conducted to develop a rubber-crawler type vehicle as a traveling device for harvesting water-dropwort cultivated in water contained paddy rice field in winter season. Methods: A commercial rubber-crawler type vehicle was used to investigate application of rubber crawler to the paddy rice field as preliminary test. As the result of the preliminary test, a both prototype traveling device with rubber crawlers for a water-dropwort harvest was designed with inclination of $45^{\circ}$ at the front-end and rear-end of crawler under the basic water depth of 0.6 m in the paddy rice field. The device was fabricated and attached to the experimental harvesting test devices on the front of the prototype vehicle. The size of the prototype crawler vehicle with a harvesting part is $2,800{\times}1,460{\times}1,040 $ (mm) ($L{\times}W{\times}H$) with weight of 9.21 kN (maximum). Sizes of the crawler of prototype vehicle are ground contact length of 900 mm, width of 180 mm, height of 1,070 mm and distance between center to center of crawlers of 720 mm. The side-overturn angle of the prototype was $26.4^{\circ}$. Results: Driving performance of the prototype vehicle in water contained paddy field were good at both forward and reverse (backward) directions as weights were applied. The drawbar pull and the maximum sinking depth of the prototype vehicle were 3.5 kN and 0.13 m respectively at water depth of 0.5 m, when the weight and bearing capacity of the prototype rubber crawler in the paddy field were 8.51 kN and 26.3 $kN/m^2$, respectively. Conclusions: Results of the driving test performance of the prototype crawler in paddy rice field at the water depth of 0.5 m were satisfactory. The prototype had enough drawbar pull and driving ability in the deep water contained paddy field.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.20 no.3
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• pp.83-91
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• 2021

A crawler crane, which consists of a lattice boom, a driving system, and a movable vehicle, is widely used on construction sites. The crawler crane often traverses rough terrain at these sites; as a result, an overload limiter needs to be installed on the crane to prevent it from overturning and breaking. In this paper, we studied the distributed load change in relation to boom length and the angle of rotation of the roller that comes in direct contact with the grounded track shoe. First, we developed a 3D model of a crawler crane and meshed it for finite elements. Then, we performed finite element analysis to derive the load on the roller. Finally, we graphed and examined the roller distributed load data of the case according to boom length and rotation angle. By detecting the load on the roller of the crawler crane, we can predict the potential for the crane to overturn before it happens.