• Title/Summary/Keyword: bicycle-pedal

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DEVELOPMENT OF INNER-SPHERICAL CONTINUOUSLY VARIABLE TRANSMISSION FOR BICYCLES

  • Park, M.W.;Lee, H.W.;Park, N.G.;Sang, H.S.
    • International Journal of Automotive Technology
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    • v.8 no.5
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    • pp.593-598
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    • 2007
  • A new continuously variable transmission for bicycles(B-CVT) is developed by using a traction drive mechanism having inner and outer spherical rotors. The B-CVT has high power efficiency, large torque capacity, improved drivability and good packageability. The ratio change mechanism for the B-CVT is very simple, in contrast with other traction drive CVTs. After completing a conceptual design, a performance analysis and a detail design, a prototype of the B-CVT has been manufactured. The prototype has rated power of 100 watts, pedal speed of 6 rad/s and an overall speed ratio of 1.0-4.0. A bench test and an actual bicycle test have been performed to verify the practicability of the B-CVT.

CONCEPTUAL DESIGN OF INNER-SPHERICAL CONTINUOUSLY VARIABLE TRANSMISSION FOR BICYCLE USAGE

  • SEONG S. H.;RYU J. H.;LEE H. W.;PARK N. G.
    • International Journal of Automotive Technology
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    • v.6 no.5
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    • pp.467-473
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    • 2005
  • A continuously variable transmission (CVT) with an inner spherical traction drive was conceptually designed for bicycle usage. The range of the overall speed ratio is from 1.0 to 4.5. The rated power and pedal speed are 100 Watts and 6 rad/s, respectively. The peculiar packageability, high-level power efficiency and high torque capacity were considered in the design process. A compact CVT that can be installed within a $244\times125\times160mm^3$ space and is above 0.9 in efficiency for the rated values was numerically designed. The distribution of efficiency according to the input torque and input speed were calculated. Gradeability in the prescribed operation mode was simulated.

Hula-twist, a Supramolecular Photoisomerization Reaction Mechanism in Reactions of Photosensitive Biopigments

  • Liu, Robert S.H.
    • Journal of Photoscience
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    • v.9 no.2
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    • pp.1-4
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    • 2002
  • Hula-twist is a volume-conserving photoisomerization reaction mechanism postulated in 1985 to account for the rapid photoisomerization of the retinyl chromophore in rhodopsin. The requisite stereochemical consequence of simultaneous isomerization of a double bond and an adjacent single bond has recently been demonstrated in isomerization of pre-vitamin D in an organic glass and by many other examples of organic systems already reported in the literature This paper reports the consequence in applying the mechanism to the primary photochemical process of several photosensitive biopigments: bilirubin, photoactive yellow protein, bacteriorhodopsin and rhodopsin. It is shown that the anchored nature of the chromophores must first be taken into consideration.

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Path Tracking Motion Control using Fuzzy Inference for a Parking-Assist System (퍼지 추론을 이용한 주차지원 시스템의 경로추종 운동제어)

  • Kim, Seung-Ki;Chang, Hyo-Whan;Kim, Chang-Hwan
    • Transactions of the Korean Society of Automotive Engineers
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    • v.17 no.2
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    • pp.1-9
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    • 2009
  • A parking-assist system is defined that a driver adjusts vehicle velocity through brake pedal operation and parking-assist system controls the motion of the vehicle to follow a collision-free path. In this study, a motion control algorithm using Fuzzy inference is proposed to track a maneuvering clothoid parallel path. Simulations are performed under SIMULINK environments using MATLAB and CarSim for a vehicle model. As the vehicle model in MATLAB a bicycle model is used including lateral dynamics. The simulation results show that the path tracking performance is satisfactory under various driving and initial conditions.

Pedaling Characteristics of Cycle Ergometer Using the MR Rotary Brake (MR 회전형 브레이크를 적용한 자전거 에르고미터의 주행 특성)

  • Yoon, Y.I.;Kwon, T.K.;Kim, D.W.;Kim, J.J.;Kim, N.G.
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.57 no.9
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    • pp.1669-1673
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    • 2008
  • A new cycle ergometer using a Magneto-Rheological (MR) rotary brake system has been developed for rehabilitation of hemiplegia patients to reduce uneven pedaling characteristics. For this purpose, a control method to adjust the resistance of the MR rotary brake in real time based on the magnitude of the muscular force exerted by the subject has been devised so that the mechanical resistance to the pedaling can be minimized when the affected leg was engaged for pedaling. A series of experiments were carried out with and without the engagement of this real-time control mode of MR rotary brake at different pedaling rate to find out the effect of the real-time control mode. The characteristics of the pedaling for these specific conditions were analyzed based on the variations in angular velocities of the pedal unit. The results showed that the variations in the angular velocities were decreased by 42.9% with the control mode. The asymmetry of pedaling between dominant and non-dominant leg was 19.63% in non-control mode and 1.97% in the control mode. The characteristics of electromyography(EMG) in the lower limbs were also measured. The observation showed that Integrated EMG(IEMG) reduced with the control mode. Therefore, the new bicycle system using MR brake with the real time control of mechanical resistance was found to be effective in recovering the normal pedaling pattern by reducing unbalanced pedaling characteristics caused by disparity of muscular strength between affected and unaffected leg.

Feedback Phenomenon in Technology Art (예술 공학의 피드백)

  • Kim Hyung-Gi
    • Science of Emotion and Sensibility
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    • v.8 no.4
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    • pp.423-433
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    • 2005
  • The computer hardware development has provided many chances of emergence between art and technology. In many cases today's interactive artworks cannot be completed without audience's participation. The interactive production process with technical supplementation can be celled feedback. Mr. Nam Jun Paik showed 'Participant TV' that interacts with audience's response in real time. It means artwork changes with the constantly changing value from the data set from human visual perception. Dan Graham showed another feedback related work, which delays 5second playback in mirror that implies consequence of time. Today's media art has to sublimate coincidence, time ant audience into philosophical artwork through consonance that comes with video and sound as we can see from Bill Viola. Stelarc produced artworks. That use input data that is weak signals from brain, muscles. Through a terminal display with player, body expanded meaning of media. Jeffrey Shaw's 'Legible City' provided a fabrication of the reality with the interaction of bicycle's pedal speed and steering direction that is controlled by 4river. RE:MARK used microphone as input device as Edmond Couchot's 'Je same a la vent' and Nam Jun Paik's 'Participant TV' did. There is no communication without feedback between human being. The reality makes audience involved into artworks. That is the reason why feedback has to be natural. Through the feedback process, the originality of the idea is altered by audience. The feedback is not just part of flesh of artwork rather skeleton of it. Technological showoff cannot be art itself The perfection of technological application plan helps feedback that interacts with audience naturally in order that audience hoes not feel the feedback as artificial plan. Interactive media art has to be evolved into new media form with new integration feedback technology.

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