Effect of Hand Force on Rotational Stiffn^|^eacute;ss of a Bicycle Handle

This study aims at clarifying the effects of internal force between human arms and a bicycle handle on the rotational stiffness of the bicycle handle. Rotational stiffness of the handle is determined by internal force stiffness and stiffness of human arms and body. We use the three-link model to analyze the rotational stiffness due to the internal force, and measure the rotational stiffness on level roads and slopes as a function of the internal force, Through theoretical calculation and experimental results, it is reveraled that the stiffness due to internal force is significantly large in comparison with the stiffness due to the muscle conrraction of arms and body. Moreover, the effective way to generate rotational stiffness of a bicycle handle by using internal force is proposed in this paper.