Running, walking, flying and swimming are all processes in which animals produce propulsion by executing rhythmic motions of their bodies. Dynamical stability of the locomotion is hardly automatic: millions of older people are injured by falling each year. Stability frequently requires sensory feedback. We investigate how organisms obtain the information they use in maintaining their stability. Assessing stability of a periodic orbit of a dynamical system requires information about the dynamics of the system off the orbit. For locomotion driven by a periodic orbit, perturbations that "kick" the trajectory off the orbit must occur in order to observe convergence rates toward the orbit. We propose that organisms generate excitations in order to set the gains for stabilizing feedback. We hypothesize further that these excitations are stochastic but have heavy-tailed, non-Gaussian probability distributions. Compared to Gaussian distributions, we argue that these are more effective for estimating stability characteristics of the orbit. Finally, we propose experiments to test the efficacy of these ideas.

中文翻译：

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运动：利用噪声进行状态估计。

跑步，散步，飞行和游泳都是动物通过执行其身体有节奏的运动来产生推进力的过程。运动的动态稳定性很难自动实现：每年摔倒都会伤及数百万的老年人。稳定性经常需要感觉反馈。我们调查了生物如何获得其用于维持其稳定性的信息。评估动力系统周期轨道的稳定性需要有关系统离开轨道的动力学信息。对于由周期性轨道驱动的运动，为了观察朝向轨道的收敛速度，必须发生将轨道“踢出”轨道的扰动。我们建议生物体产生激发，以设置稳定反馈的增益。我们进一步假设这些激励是随机的，但具有重尾的非高斯概率分布。与高斯分布相比，我们认为这些分布对于估计轨道的稳定性更有效。最后，我们提出实验以测试这些想法的有效性。