Customization design is a trend for developing a bicycle in recent years. Thus, the comfort of riding a bike
is an important factor that should be paid much attention to while developing a bicycle. From the
viewpoint of ergonomics, the concept of “fitting object to the human body” is designed into the bicycle
frame in this study. Firstly, the important feature points of riding posture were automatically detected by
the image processing method. In the measurement process, the best riding posture was identified
experimentally, thus the positions of feature points and joint angles of human body were obtained.
Afterwards, according to the measurement data, three key points: the handlebar, the saddle and the
crank center, were identified and applied to the frame design of various bicycle types. Lastly, this study
further proposed a frame size table for common bicycle types, which is helpful for the designer to design
a bicycle.