Nishii Jun
Department of Physics, Biology and Informatics, Yamaguchi University, Yoshida, Yamaguchi 753-8512, Japan.
J Theor Biol. 2006 Feb 7;238(3):636-45. doi: 10.1016/j.jtbi.2005.06.027. Epub 2005 Aug 5.
Legged locomotion requires the determination of a number of parameters such as stride period, stride length, order of leg movements, leg trajectory, etc. How are these parameters determined? It has been reported that the locomotor patterns of many legged animals exhibit common characteristics, which suggests that there exists a basic strategy for legged locomotion. In this study we derive an equation to estimate the cost of transport for legged locomotion and examine a criterion of the minimization of the transport cost as a candidate of the strategy. The obtained optimal locomotor pattern that minimizes the cost suitably represents many characteristics of the pattern observed in legged animals. This suggests that the locomotor pattern of legged animals is well optimized with regard to the energetic cost. The result also suggests that the existence of specific gait patterns and the phase transition between them could be the result due to optimization; they are induced by the change in the distribution of ground reaction forces for each leg during locomotion.
腿部运动需要确定多个参数，如步幅周期、步幅长度、腿部运动顺序、腿部轨迹等。这些参数是如何确定的呢？据报道，许多有腿动物的运动模式表现出共同特征，这表明存在一种腿部运动的基本策略。在本研究中，我们推导了一个用于估算腿部运动运输成本的方程，并研究了将运输成本最小化的标准作为该策略的一个候选方案。所获得的使成本最小化的最优运动模式适当地体现了在有腿动物中观察到的运动模式的许多特征。这表明有腿动物的运动模式在能量成本方面得到了很好的优化。该结果还表明，特定步态模式的存在以及它们之间的相变可能是优化的结果；它们是由运动过程中每条腿的地面反作用力分布变化所诱导的。
