小型二段階ツイストストリングアクチュエーションシステム：モデリングと検証
A compact two-phase twisted string actuation system: Modeling and validation
マルチストリングのツイストとオーバーツイストの二段階で81%の高収縮率を実現する小型アクチュエータを提案し、半径予測モデルの改良と寿命試験で有効性を検証した。
著者: Mahmoud Tavakoli, Rafael Batista, Pedro Neto
分類: cs.RO
原文アブストラクト
In this paper, we propose a compact twisted string actuation system that achieves a high contraction percentage (81%) on two phases: multi string twist and overtwist. This type of system can be used in many robotic applications, such as robotic hands and exoskeletons. The overtwist phase enables the development of more compact actuators based on the twisted string systems. Furthermore, by analyzing the previously developed mathematical models, we found out that a constant radius model should be applied for the overtwisting phase. Moreover, we propose an improvement of an existing model for prediction of the radius of the multi string system after they twist around each other. This model helps to better estimate the bundle diameter which results in a more precise mathematical model for multi string systems. The model was validated by performing experiments with 2, 4, 6 and 8 string systems. Finally, we performed extensive life cycle tests with different loads and contractions to find out the expected life of the system.
