The Development of the Automatic Transmission for Bicycle Using Internally Geared Hub

내장기어허브를 이용한 자전거 자동변속장치의 개발

  • Lee, Man Ho (Graduate School of Automotive Engineering, Kookmin Univ.) ;
  • Choi, Jun Ho (Graduate School of Automotive Engineering, Kookmin Univ.) ;
  • Lee, Kun Sang (School of Mechanical System Engineering, Kookmin Univ.)
  • 이만호 (국민대학교 자동차공학전문대학원) ;
  • 최준호 (국민대학교 자동차공학전문대학원) ;
  • 이건상 (국민대학교 기계시스템공학부)
  • Received : 2013.12.26
  • Accepted : 2014.02.24
  • Published : 2014.04.01


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.


Bicycle;Internally Geared Hub;Automatic Transmission


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