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Lee, Boo-Youn;Lee, Hyun-Woo
- Transactions of the Korean Society of Mechanical Engineers A
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- v.31 no.2 s.257
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- pp.269-276
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- 2007
Optimal thickness and shape of the pedal arm of an automotive clutch is determined, using the numerical optimization technique, by solving the size and shape optimization problems to minimize its weight. For the optimization problems, two cases of stress and displacement constraints are considered: one from the vertical, and the other from the transverse stiffness test condition. The result of the transverse case is shown to be more conservative than that from the vertical case, being determined as the final optimum.
https://doi.org/10.3795/KSME-A.2007.31.2.269 인용 PDF KSCI

Han, Moon-Sik;Cho, Jae-Ung
- Journal of the Korean Society of Manufacturing Technology Engineers
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- v.21 no.1
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- pp.51-57
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- 2012
This study investigates structural and fatigue analyses at bicycle pedal. Maximum deformation at model 1 is 2 times as much as model 2 at static analysis. Models 1 and 2 have the possibility of the weakest strength at the part of contact with chain gear. Among the cases of nonuniform fatigue loads at Models 1 and 2, 'SAE bracket history' with the severest change of load becomes most unstable but 'Sample history' becomes most stable. In case of 'Sample history' with the average stress of 0 to $-10^4$ MPa and the amplitude stress of 0 to $10^4$ MPa, the possibility of maximum damage becomes 4%. This stress state can be shown with 5 to 7 times more than the damage possibility of 'SAE bracket history' or 'SAE transmission'. The analysis result of this study can be effectively utilized with the safe design of pedal.
https://doi.org/10.7735/ksmte.2012.21.1.051 인용 PDF KSCI

Lee, Man Ho;Choi, Jun Ho;Lee, Kun Sang
- Transactions of the Korean Society of Mechanical Engineers A
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- v.38 no.4
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- pp.393-400
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- 2014
In this study, an automatic transmission was developed for a bicycle. This transmission uses the pedal rpm and riding speed information for efficient riding. This transmission was installed on a bicycle using an internally geared hub. The automatic transmission was developed for a beginner to ride with proper gear changes. Indoor ride tests were performed to assess the performance of this transmission. Here, a 'beginner' is defined as a bicycle rider who can maintain a riding power of ~150W with a maximum heart rate of ~80%. Furthermore, 'ride with proper gear change' means that the rider could ride the bicycle while maintaining an efficient pedal rpm by the automatic transmission. One expert and four beginners participated in the ride test. The expert was chosen for the comparison with the beginners. To minimize environmental disturbances, the ride test was performed indoors. In this test, two types of gear changes manual and automatic were tested on two types of roads a road with a gradual incline of 0-3% and a road that simulates the bicycle road along the Han river in Seoul. The results of the ride tests show that the algorithm applied for the automatic transmission helps beginners to ride the bicycle efficiently.
https://doi.org/10.3795/KSME-A.2014.38.4.393 인용 PDF KSCI