Proprioceptive Actuator Design in the MIT Cheetah: Impact Mitigation and High-Bandwidth Physical Interaction for Dynamic Legged Robots
Proprioceptive Actuator Design in the MIT Cheetah: Impact Mitigation and High-Bandwidth Physical Interaction for Dynamic Legged Robots
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DOI：
10.1109/tro.2016.2640183
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发表时间：
2017-06-01
影响因子：
7.8
通讯作者：
Kim, Sangbae
中科院分区：
文献类型：
--
作者：
Wensing, Patrick M.;Wang, Albert;Kim, Sangbae
高动态腿式机器人的驱动系统设计一直是机器人研究的重大挑战之一。用于制造应用的传统致动器难以满足高速运动的设计要求，例如需要高扭矩密度和管理动态物理相互作用的能力。为了应对这一挑战，本文提出了一种本体感受驱动范式，使leggedmachines高度动态性能。本体感受驱动在关节处使用并置的力控制来有效地控制动态条件下足部处的接触相互作用。模态分析的减少腿模型和尺寸分析的直流电机地址的主要原则，实现这一范例。在腿式机器领域，这种模式提供了高扭矩密度、高带宽力控制以及通过反向驱动能力减轻冲击的能力的独特组合。我们引入了一个新的指标，名为“影响缓解因子”（IMF），以量化backdrivability的影响，这使得设计比较广泛的机器人。麻省理工学院的猎豹腿，并显示有一个国际货币基金组织，是与其他四足动物系列弹簧处理的影响。该设计使Cheetah能够在动态弹跳过程中控制接触力，接触时间低至85 ms，峰值力超过450 N。麻省理工学院猎豹的独特能力，实现了高速三维运行和跳跃的冲击鲁棒力控制操作，建议更广泛地实施这种整体驱动方法。
Designing an actuator system for highly dynamic legged robots has been one of the grand challenges in robotics research. Conventional actuators for manufacturing applications have difficulty satisfying design requirements for high-speed locomotion, such as the need for high torque density and the ability to manage dynamic physical interactions. To address this challenge, this paper suggests a proprioceptive actuation paradigm that enables highly dynamic performance in leggedmachines. Proprioceptive actuation uses collocated force control at the joints to effectively control contact interactions at the feet under dynamic conditions. Modal analysis of a reduced leg model and dimensional analysis of DC motors address the main principles for implementation of this paradigm. In the realm of leggedmachines, this paradigm provides a unique combination of high torque density, high-bandwidth force control, and the ability to mitigate impacts through backdrivability. We introduce a new metric named the "impact mitigation factor" (IMF) to quantify backdrivability at impact, which enables design comparison across a wide class of robots. The MIT Cheetah leg is presented, and is shown to have an IMF that is comparable to other quadrupeds with series springs to handle impact. The design enables the Cheetah to control contact forces during dynamic bounding, with contact times down to 85 ms and peak forces over 450 N. The unique capabilities of the MIT Cheetah, achieving impact-robust force-controlled operation in high-speed three-dimensional running and jumping, suggest wider implementation of this holistic actuation approach.