论文标题
PD控制的双足步行机器人的局部稳定性
Local Stability of PD Controlled Bipedal Walking Robots
论文作者
论文摘要
我们为PD跟踪控制定律建立了稳定结果。连续机器人系统的PD控制定律的稳定性是一个已建立的结果，我们将其扩展到混合机器人系统，这是连续和离散事件的交替序列。两足动物的机器人将腿部旋转作为连续的事件，而脚击则是离散的事件。此外，由于脚和地面之间的相互作用，双头大大不足。对于每个连续事件，我们确定可以通过适当调整PD增益来调节跟踪误差的收敛速率；对于每个离散事件，我们确定这种收敛速率通过对混合零动力学的假设充分克服了非线性影响。主要的贡献是1）在机器人系统不足的PD控制定律的稳定性结果以及2）在假设其投影对混合零动力学的指数稳定性下，混合周期性轨道的指数最终界限。到最后，我们将在模拟中以2链接双体步行者进行验证这些结果。
We establish stability results for PD tracking control laws in bipedal walking robots. Stability of PD control laws for continuous robotic systems is an established result, and we extend this for hybrid robotic systems, an alternating sequence of continuous and discrete events. Bipedal robots have the leg-swing as the continuous event, and the foot-strike as the discrete event. In addition, bipeds largely have underactuations due to the interactions between feet and ground. For each continuous event, we establish that the convergence rate of the tracking error can be regulated via appropriate tuning of the PD gains; and for each discrete event, we establish that this convergence rate sufficiently overcomes the nonlinear impacts by assumptions on the hybrid zero dynamics. The main contributions are 1) Extension of the stability results of PD control laws for underactuated robotic systems, and 2) Exponential ultimate boundedness of hybrid periodic orbits under the assumption of exponential stability of their projections to the hybrid zero dynamics. Towards the end, we will validate these results in a 2-link bipedal walker in simulation.
