• Journal of Drive and Control
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• v.19 no.3
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• pp.32-38
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• 2022

The in-wheel drive gearbox for military special vehicles converts the high-speed & low-torque output generated by the electric servomotor, into low-speed & high-torque mechanical power. As the vehicle is remotely maneuvered in mountainous terrain, wet fields, rough terrain, etc., the gearbox must generate a maximum input speed exceeding 5,000 rpm, a maximum torque of 245 Nm, and MTBF of 9,600 km. The purpose of this study was to analyze the failure mode of the gearbox, to ensure the durability of the in-wheel drive gearbox. Also, the field load test data of the vehicle was analyzed, the acceleration durability test standards were established, the acceleration durability test was conducted, and the durability test results were analyzed as well.

• Journal of Applied Reliability
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• v.17 no.4
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• pp.273-279
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• 2017

Purpose: Recently, Issues on security for vehicles are getting increased all around the world. Especially, hood panel needs to be thinner for the protection of pedestrians. But thinner panel makes durability get worse. So, it is needed to satisfy both of them. Methods: Durability effectiveness will be studied because properties and assembly allowance of over-slam bumper mostly affects durability of hood panel. Overlap of over-slam bumper can be made in production line and it can affect durability of spot welding in hood inner panel. Daguchi method is used to catch the condition in which load gets smaller and location, hardness and quantity of overlap are selected to be factors. Durability effectiveness is analyzed with the factors. Result: the mechanism that affects on spot welding is identified. The test was conducted in both open/close and driving condition and the relation between both conditions is analyzed. Conclusion: The test contributed to durability of hood panel with optimization of over-slam bumper.

• Transactions of the Korean Society of Automotive Engineers
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• v.15 no.2
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• pp.28-34
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• 2007

In design stage of vehicles, the application of virtual durability analysis techniques enables us to cut down the necessary time and cost to carry out various physical experiments. In this study, computer simulations of vehicle suspensions were carried out with DADS program including component flexibility, and the durability analysis of vehicle components was executed with MSC/Fatigue program using the load history obtained from vehicle dynamic simulation. Driving test of a vehicle was also carried out to obtain precise input data for the durability analysis, and the results of virtual durability analysis were compared to those of experiments.

• Journal of Applied Reliability
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• v.16 no.1
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• pp.7-14
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• 2016

Purpose: The purpose of this study is to development the fire evaluating test methods for the Electric hair dryers. Methods: We was designed FMEA (Failure mode and effects analysis) in order to analyze the fire mechanism on the electric hair dryers and designed evaluating test methods (Durability tests on the environment, Mechanical durability tests) obtained through the two-step QFD (Quality Function Depolyment) and tested. Conclusion: We verified the evaluating fire test methods on the electric hair dryers through the analysis of the test results and some reproduction test.

• Journal of the Korean Society of Industry Convergence
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• v.24 no.5
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• pp.537-546
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• 2021

Remanufacturing is one of the most important resource recycling technology in response to resource depletion and environmental pollution. Domestic remanufacturing industry don't invigorate compared to other advanced countries because of low price and reliability of remanufactured product. In this study, remanufactured hydraulic pump and solenoid valve were evaluated durability by accelerated life test. In order that standard remanufacturing process was developed by core analysis and failure mode and effect analysis. And cores were remanufactured by standard remanufacturing process. For accelerated life test, the evaluation item and criteria were deduced by results of FMEA, reliability standards and enterprise interior criteria. To evaluate durability of remanufactured product, the remanufactured hydraulic pump and solenoid valve were evaluated performance after accelerated life test and the results were satisfied with criteria. This study showed that remanufactured products have a similar level of durability to new products by definition of remanufacturing.

• Tribology and Lubricants
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• v.38 no.4
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• pp.128-135
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• 2022

In the product development process, the reliability of the product can be secured through durability tests. However, since the durability test method is expensive and time consuming, a method to save time and money by utilizing virtual product development (VPD) is required. However, research on the accuracy of the results of virtual product development is required. In this paper, an accelerated durability test was designed and conducted using a planetary gear decelerator. And an analysis model under the same conditions was created and simulated. To correlate the results of the experiment with the results of the analytical model, created a model that can discriminate the wear region using one of the data mining methods, the k-means algorithm method and HSV (Hue, Saturation, Value). The wear area is compared by counting the number of pixels defined as wear through a discrimination model. A similar ratio was calculated by comparing the pixel ratio of the area determined as wear in the entire area. It showed a similar ratio of about 70%, and it is necessary to improve the discrimination method.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.30 no.5
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• pp.127-133
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• 2002

The general requirements to achieve the structural integrity of the airframe are described in the military specification, MIL-STD-1530A. One of these requirements is the durability and damage tolerance of the airframe, which should be shown through the analysis and test based on the related specifications. This paper introduces the full scale durability test to evaluate the structural safety and durability of the basic trainer, KT-1. The test was performed according to the procedure in the military specification. The flight by flight load spectrum was developed by KT-1 fatigue load criteria and used for the durability test. The durability test had been performed for 4 service lives and was completed successfully. Therefore, it was shown that KT-1 airframe satisfied the durability requirements.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.9 no.6
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• pp.16-20
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• 2010

This study proposes a structural design method for the upper control arm installed at the rear side of a SUV. The weight of control arm can be reduced by applying the design. In this research, the former includes optimization technology, and the latter the technologies for selecting aluminum as a steel-substitute material. Strength assessment is the most important design criterion in the structural design of a control arm. At the proto design stage of a new control arm, FE (finite element) analysis is often utilized to predict its strength. In this study, the kriging interpolation method is adopted to obtain the minimum weight satisfying the strength constraint and durability criteria. The optimum results determined from the in-house program are compared with those of ANSYS WORKBENCH. The durability assessment is obtained by a index of fatigue durability and trial & error method, MSC. Fatigue program.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.9
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• pp.3889-3894
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• 2012

The platform of railroad station for domestic passenger train has been operated at two categories like the platforms if low level(500mm, mainline) and high level(1,135mm, metropolitan subway line). To operate both metropolitan subway line and mainline railroad safely, it is essential to develop the doorstep equipment of railway vehicle regardless of low and high level platforms. On the other hand, the domestic test standard at durability and reliability of doorstep equipment has not been existed until now. This study aims at the development on doorstep equipment of telescopic sliding type for low and high level platforms. Durability analysis with VPD(Virtual Product Development) techniques are performed and the durability standard & qualification life through the rig test during no failure test time is examined in accordance with reliability qualification test.

• Journal of Applied Reliability
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• v.18 no.1
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• pp.40-48
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• 2018

Purpose: This research is to develop Trailer Durability Test of towing device, in order to cover usage conditions of bike type as well as general type trailer. With the diversification of leisure activities, the population that enjoys various sports and leisure has increased rapidly, and the number of vehicles equipped with camping trailers and bike carriers is also increasing steadily. The purpose of this study is to develop a durable vehicle that has no problem in various customer conditions. Methods: We measured the input load under various conditions of the user by attaching load cell to the body fixing part and towing ball of the towing device. The load in various modes was measured, and the difference between the trailer and the bike carrier type was compared and analyzed. Results: Due to the difference in fixing method and weight between the two types, the trailer has a large longitudinal force and the bike type has a large vertical force. Therefore, it is necessary to durability test method capable of satisfying all longitudinal force and vertical force. Conclusion: We improved the durability test of the towing device by changing the test surface. The new mode has made it possible to shorten the durability test schedule by increasing test efficiency.