Anticipatory Control of Momentum for Bipedal Walking on Uneven Terrain
Anticipatory Control of Momentum for Bipedal Walking on Uneven Terrain
复制标题
DOI：
10.1038/s41598-019-57156-6
复制
发表时间：
2020-01-17
影响因子：
4.6
通讯作者：
Kuo, Arthur D.
中科院分区：
文献类型：
--
作者：
Darici, Osman;Temeltas, Hakan;Kuo, Arthur D.
人类和其他行走的两足动物经常遇到并补偿不平坦的地形。例如，它们可能会在踩着石头过河时调节身体的动量。我们研究了该做什么和看多远，作为一个简单的最优控制问题，控制向前的动量以补偿地形高度的阶跃变化，并恢复稳定的步态，相对于标称行走没有时间损失。我们模拟了平面的，像人类一样的行走，像腿一样的腿，并发现最经济的控制是相当刻板的。它开始于在向上一步之前的几步获得动量，预计在该步上失去的动量，然后以另一次加速结束，以重新获得动量。类似的模式可以缩放到各种条件，包括向上或向下的步骤，但与没有预期的补偿相比，允许显著降低的总能量和峰值功率需求。我们定义了一个“持续时间”的度量从瞬态衰减响应后的干扰，描述如何保持动量之间的步骤，以及多远的干扰应该计划。对势头的预期控制有助于在经济上克服不平坦的地形。
Humans and other walking bipeds often encounter and compensate for uneven terrain. They might, for example, regulate the body's momentum when stepping on stones to cross a stream. We examined what to do and how far to look, as a simple optimal control problem, where forward momentum is controlled to compensate for a step change in terrain height, and steady gait regained with no loss of time relative to nominal walking. We modeled planar, human-like walking with pendulum-like legs, and found the most economical control to be quite stereotypical. It starts by gaining momentum several footfalls ahead of an upward step, in anticipation of the momentum lost atop that step, and then ends with another speed-up to regain momentum thereafter. A similar pattern can be scaled to a variety of conditions, including both upward or downward steps, yet allow for considerably reduced overall energy and peak power demands, compared to compensation without anticipation. We define a "persistence time" metric from the transient decay response after a disturbance, to describe how momentum is retained between steps, and how far ahead a disturbance should be planned for. Anticipatory control of momentum can help to economically negotiate uneven terrain.