パワーアシスト装置の研究（第１報：重力負荷と動的負荷に異なるアシスト比を設定する制御法の提案）
林原 靖男， 谷江 和雄， 荒井 裕彦
日本機械学会論文集Ｃ編, Vol.61, No.591, pp.4318-4325, 1995.
［和文要旨］
本論文では，外骨格型のパワーアシスト装置において，アクチュエータの最大出力トルクの制限内で均一なアシスト比を維持しつつ，動作させることの重要性を指摘するとともに，それを実現する一手法として，負荷を重力負荷と動的負荷に分け，それぞれに個別のアシスト比を設定する手法を提案した．その具体的内容は，重力負荷のアシスト比を優先的に設定し，重力負荷をアシストしたアクチュエータが持つ残りの力・トルクで，動的負荷のアシスト比を決定するという考えに基づく．手法を一自由度系で定式化し，特徴を論じると共に，実験によりその有効性を評価した．
Study on Power Assist System
(1st Report, Proposal of a Control Method with Different Assist Ratios for Gravity Load and Dynamic Load)
Yasuo Hayashibara, Kazuo Tanie and Hirohiko Arai
Transactions of the Japan Society of Mechanical Engineers (C)，Vol.61, No.591, pp.4318-4325, 1995.
[Abstract]
This paper proposes a control method for the power assist system which is used to attenuate the load force. In the power assist system, selecting suitable power assist ratio is important. The power assist ratio must be selected with consideration of the maximum torque of actuators used in the system. When the system has an excessively large ratio, actuator saturation occurs which cases the lack of maneuverability and stability. To avoid such saturation problems, a control method in which the gravity load is assisted with a ratio different from one for the dynamic load is proposed. The gravity load applies to the operator every time a load is supported. The dynamic load applies to the operator only when the operator moves the load. With this consideration in mind, the method proposes that the ratio for the dynamic load should be selected considering the remaining actuator torque usable after the ratio for the gravity load is determined considering the operator's capability. The control method is formulated for a single-axis power assist system and the effectiveness of the method is confirmed by experiments.
[Keywords]
Mechatronics and Robotics, Maneuverability, Human Engineering, Power Assist System, Teleoperation, Master-Slave Manipulator, Human-robot System