Hull M L, Gonzalez H
Department of Mechanical Engineering, University of California, Davis 95616.
J Biomech. 1988;21(10):839-49. doi: 10.1016/0021-9290(88)90016-4.
The contribution of this paper is a bivariate optimization of cycling performance. Relying on a biomechanical model of the lower limb, a cost function derived from the joint moments developed during cycling is computed. At constant average power, both pedalling rate (i.e. rpm) and crank arm length are systematically varied to explore the relation between these variables and the cost function. A crank arm length of 170 mm and pedalling rate of 100 rpm correspond closely to the cost function minimum. In cycling situations where the rpm deviates from 100 rpm, however, crank arms of length other than 170 mm yield minimum cost function values. In addition, the sensitivity of optimization results to both increased power and anthropometric parameter variations is examined. At increased power, the cost function minimum is more strongly related to the pedalling rate, with higher pedalling rates corresponding to the minimum. Anthropometric parameter variations influence the results significantly. In general it is found that the cost function minimum for tall people occurs at longer crank arm lengths and lower pedalling rates than the length and rate for short people.
本文的贡献在于对骑行性能进行双变量优化。基于下肢生物力学模型，计算了从骑行过程中产生的关节力矩导出的成本函数。在恒定平均功率下，系统地改变踏频（即每分钟转速）和曲柄长度，以探究这些变量与成本函数之间的关系。170毫米的曲柄长度和100转/分钟的踏频与成本函数最小值密切对应。然而，在踏频偏离100转/分钟的骑行情况下，长度不是170毫米的曲柄会产生成本函数最小值。此外，还研究了优化结果对功率增加和人体测量参数变化的敏感性。在功率增加时，成本函数最小值与踏频的相关性更强，较高的踏频对应最小值。人体测量参数变化对结果有显著影响。一般发现，高个子人群的成本函数最小值出现在比矮个子人群更长的曲柄长度和更低的踏频处。
