Study on Casting Manipulation : 1st Report, Manipulator with Flexible String and its Swing Motion Control

• Published in: Transactions of the Japan Society of Mechanical Engineers Series C Vol. 64; no. 626; pp. 3854 - 3861
• Main Authors: ARISUMI, Hitoshi, KOTOKU, Tetsuo, KOMORIYA, Kiyoshi
• Format: Journal Article
• Language: Japanese
• Published: The Japan Society of Mechanical Engineers 25.10.1998
• Subjects: Casting; Flexible Link Mechanism; Manipulation; Non-Holonomic System; Robotics; Swing Motion
• ISSN: 0387-5024; 1884-8354
• DOI: 10.1299/kikaic.64.3854

A casting manipulator is introduced as a new type of manipulator, which includes flexible parts, such as a string, in its link mechanism. In a simple configuration, a string is wound around a reel attached on a rigid link and the rigid link is actuated in order to generate the necessary motion of a gripper attached at the end of the string. The merit of this type of manipulator is its large work space compared with its simple mechanism and its size. After generating swing motion, the gripper is thrown to a target by releasing a lock of the string and catches it with changing the length of the string. In this paper, we consider the planner two link casting manipulator, that is a non-holonomic system. First, we show the process of casting manipulation and discuss the swing motion phase. Then a method of generating a desired swing motion without the slack of the string is proposed. We investigate the method of choosing a time-periodic reference for the controlled joint by an off-line simulation chart. The effectiveness of the method is evaluated by numerical simulations.