Design studies and improvement for smart gear change mechanism of bicycles

Abstract

The automatic shifting bicycle is under development for more than 20 years. Investors didn't see the sales boom like the mountain bike in the 1980s and 1990s because of the expensive price and stability of automatic shifting mechanism. In order to make improvement for existing non-conventional and interesting rear gear change mechanism for bicycles, computer 3D CAD models are developed. Dynamic simulations in Visual Nastran 4D environment and control simulations in Matlab Simulink environment are adopted to aid the understanding of design of shifting mechanism. Torque measurement methodology, control method and optimised control algorithm is proposed to investigate the feasibility of upgrading electromechanical shifting into automatic shifting.