This study aims at improving robot dexterity and intellectual faculties by developing an anthropomorphic robot which can perform information processing tasks expressed as a sequence of continuous changes in positioning the points of fingertips in such movements as playing keyboard instrument. Humans achieve these complicated movements skillfully using finger-arm coordination. Therefore, it would also be advantageous for a robot to use fingers and arm properly in coordination. However, in design of the finger-arm coordination system, a problem arises since the system has redundant degrees-of-freedom (DOF) and it becomes necessary to allocate tasks to fingers and arm as a coordination control standard. This paper describes the observation and the analysis of human movement involved in playing a high-level tune on a keyboard instrument. From such observation and analysis, the coordination control standard will be derived. This paper also describes the development of the new manipulator WAM-8 R. Results of the analysis show that the thumb, which has three joints named CM, MP and IP, plays the pivotal role among the five fingers when keyboard playing is performed using finger-arm coordination. The following two points summarize the result. 1. During the playing, the CM joint of the thumb is mainly used to position the fingertip on the specific key of the keyboard. The IP joint has the function of placing the thumb in a suitable posture while the thumb and a finger strike the key with finger-arm coordination. In other words, precise striking is realized by coordination of three joints (CM, MP, IP) while finger and arm are coordinated. 2. Wrist movement and change in hand direction are much used with a change in the thumb posture to expand the movable range in finger-arm coordination. According to the result of the analysis described above, the new manipulator WAM-8 R was developed which has a four-DOF-thumb configuration having almost the same function as a human thumb. To estimate the WAM-8 R, we calculate the movable range in finger-arm coordination of WAM-8 R and compare it with that of a human hand. The AREA Table is introduced to represent the movable range in finger-arm coordination. Reference to the AREA Table makes it possible to refer to the type of finger capable of processing the next work point on the basis of the type of finger currently processing a work point and the distance between the present work point and the next work point. As a result, it was found that the movable range of WAM-8 R was almost equivalent to that of a human hand.
抄録全体を表示