AN EFFICIENT OPTIMUM DESIGN PROCEDURE FOR BICYCLE REAR DERAILLEURS

The rear derailleur on a multi-speed bicycle guides the running chain rapidly and precisely to a selected freewheel sprocket position withou t disengagement from the freewheel assembly. Therefore, the design of rear derailleurs is most important for designers. An efficient optimum design procedure for rear derailleurs is presented in this paper. Bas ed on an established mathematical model, a series of optimum design su b-problems derived from the original optimum design problem are formul ated and solved to meet all design requirements. The advantage of divi ding the original design problem into several sub-problems is that it makes the upper/lower bounds of design variables in each sub-problem e asier to determine. This reduces the trial-and-error efforts during it erative searching for optimum solutions. Thus, the design procedure be comes more rapid and efficient. It is worth emphasizing that the desig n procedure proposed herein is applicable to most known types of rear derailleurs.