スラック式可変ダンパが脚式移動のロバスト性と効率のトレードオフを生む
Slack-based tunable damping leads to a trade-off between robustness and efficiency in legged locomotion
腱のたるみ量を調整できる物理ダンパ機構を脚式ロボットに搭載し、外乱時に自動的にダンパが作動してロバスト性を高める一方、エネルギー消費が増えるトレードオフを実験的に示した。
著者: An Mo, Fabio Izzi, Emre Cemal Gönen, Daniel Haeufle, Alexander Badri-Spröwitz
分類: cs.RO
原文アブストラクト
Animals run robustly in diverse terrain. This locomotion robustness is puzzling because axon conduction velocity is limited to a few ten meters per second. If reflex loops deliver sensory information with significant delays, one would expect a destabilizing effect on sensorimotor control. Hence, an alternative explanation describes a hierarchical structure of low-level adaptive mechanics and high-level sensorimotor control to help mitigate the effects of transmission delays. Motivated by the concept of an adaptive mechanism triggering an immediate response, we developed a tunable physical damper system. Our mechanism combines a tendon with adjustable slackness connected to a physical damper. The slack damper allows adjustment of damping force, onset timing, effective stroke, and energy dissipation. We characterize the slack damper mechanism mounted to a legged robot controlled in open-loop mode. The robot hops vertically and planar over varying terrains and perturbations. During forward hopping, slack-based damping improves faster perturbation recovery (up to 170%) at higher energetic cost (27%). The tunable slack mechanism auto-engages the damper during perturbations, leading to a perturbation-trigger damping, improving robustness at minimum energetic cost. With the results from the slack damper mechanism, we propose a new functional interpretation of animals' redundant muscle tendons as tunable dampers.
