双足被动步行的全局稳定性分析

Analysis for Global Stability of Passive Bipeds Walking

在经典双足被动步行动力学模型的基础上,分析环境和力学参数影响下机器人被动步行的全局稳定性。计算不同模型参数下被动步行稳定不动点,采用胞胞映射计算得到不同模型参数下该动力学模型稳定单周期步态的吸引区域。研究发现双足被动步行的鲁棒性与其环境、力学参数关系密切,同时提出估计不动点吸引域形状的2个度量:最小半径与最大半径。实验结果给出被动步行稳定区域与斜坡倾角和质量比值的关系,同时通过分析某些偏离不动点较大的稳定吸引胞,以及吸引域的最小半径与最大半径的变化趋势,反映了双足被动步态的鲁棒性。

Based on the classical dynamic model of passive biped walking,the globel stability of passive bipeds walking which is influenced by the environment and mechical parameters is discussed.The calculaion about stable fix points on variable parameter is given.Cell-cell map is used to compute the attractive region of the 1-periodic steady gait of the walking model with variable parameters.It is found that the robustness of passive bipeds is connected closely to the environment and mechanical parameters.Moreover,this paper also proposes the two metrics to evaluate the shape of attractive region：minimum radius and maximum radius.Simulation results also reveal the relationship between the attractive region of passive walking and the parameters like ground slope or mass ratio.Simultaneously,the robusness of passive biped walking gaits is analyized by special attracive cell and the variable tendency with the maximum reach and the mininum reach of the attractive region.