发表机构
Georgia Institute of Technology; Northeastern University（佐治亚理工学院; 东北大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
研究双足机器人在颗粒斜坡上的运动控制问题，通过研究带防滑钉足部的地面动力学，发现中等防滑钉间距利于行走，据此设计可调整防滑钉深度的足部，应用于大小不同的双足机器人，提出以肢体为中心调节地形相互作用的新控制方法。
AI 中文摘要
双足机器人控制具有挑战性，因其接近不稳定状态，足部与地形接触的微小变化会迅速破坏运动稳定性。在刚性地形上，可通过成熟的接触力学和控制策略缓解这种脆弱性。而在可流动表面如颗粒斜坡上，足部接触会引发大的表面变形和类似固液转变，耦合地形效应与机器人动力学，导致性能不佳或失败，部分原因是缺乏可靠的可流动地形动力学表示方法。本文通过研究带防滑钉的足部（从鞋底伸出的薄板）的地面动力学，探讨控制地形响应如何改善颗粒斜坡上的双足运动。对小型（1.4千克）机器人物理双足的系统研究表明，防滑钉间距稀疏和密集分别会导致过度的地形屈服和阻力，降低性能并导致失败。中等防滑钉间距可分布相互作用力，使基底应力维持在（或低于）屈服阈值，从而能在高达30度的颗粒斜坡上行走。基于这些原理，设计了一种能主动调整防滑钉深度并适应刚性和颗粒地形的足部。还证明了有效的足部与地形相互作用原理可应用于更大（15千克）的自主双足机器人。本研究提出了一种替代传统以身体为中心的机器人控制方法的方案，即通过以肢体为中心的方法调节地形相互作用，而非通过身体运动调节地形诱导效应。
英文摘要
Bipedal robots are challenging to control because they operate close to instability, where small variations in foot-terrain contact can rapidly destabilize locomotion. On rigid terrain, bipedal robots mitigate this fragility by using well-established contact mechanics and control strategies. On flowable surfaces such as granular slopes, foot contact can induce large surface deformations and solid-fluid-like transitions, coupling terrain effects with robot dynamics, leading to underperformance or failure. This is partly due to the lack of reliable methods to represent the dynamics of flowable terrain, making it difficult to account for terrain effects in locomotion design. Here, we investigate how controlling terrain response can improve bipedal locomotion on granular slopes by studying the terradynamics of cleated feet, thin plates emanating from the foot soles. Systematic studies of a small-scale (1.4 kg) robophysical biped reveal that cleats with sparse and dense spacing lead to excessive terrain yielding and resistance, respectively, degrading performance and leading to failure. An intermediate cleat spacing distributes interaction forces to maintain substrate stresses near (or below) the yield threshold, enabling walking on granular slopes up to 30 degrees. Guided by these principles, we design a foot that actively adjusts cleat depth and accommodates both rigid and granular terrain. We also demonstrate that the principles of effective foot-terrain interaction translate to a larger (15 kg) autonomous biped. Our study presents an alternative to conventional body-centric robot control approaches, which regulate terrain-induced effects through body motion, by instead regulating terrain interactions through limb-centric approach.
Comments38 pages, 12 figures
