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第28回宇宙利用シンポジウム (2012年1月23-24日. 日本学術会議), 港区, 東京都, Space Utilization Research (January 23-24, 2012. Science Council of Japan), Minato-ku, Tokyo Japan, 資料番号: SA6000032061, レポート番号: L21

第27回宇宙利用シンポジウム (2011年1月24日-25日, 宇宙航空研究開発機構宇宙科学研究所相模原キャンパス), 相模原市, 神奈川県, The Twenty-seventh Space Utilization Symposium (January 24-25, 2011. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)(ISAS)), Sagamihara, Kanagawa Japan, The fruit fly Drosophila melanogaster responds behaviorally to gravity. It has long been believed that Drosophila senses gravity by halters, rudiment wings found in dipteran insect. Recent study demonstrates that halters are used to equilibrate the flight posture by sensing the rotational movement rather than the static effect exerted by gravity. A question could, therefore, be raised about the roles of gravity in the flight performance of D. melanogaster, which is normally used as the framework for the three-dimensional movement of the organisms on Earth. In order to gain an insight into the effects of gravity on the flight maneuverability, we examined the flying behavior of D. melanogaster under altered gravity; i.e. microgravity during parabolic flight, centrifugal hypergravity. D. melanogaster, under 1G control, was frequently observed to walk up and then to fly downward along a short straight path. Under short-term microgravity during parabolic flight, D. melanogaster was observed to fly randomly for longer period. We frequently observe some flies collided the chamber wall and failed in landing. In addition, it was revealed that some specimens were levitating without wing beating under microgravity. Under hypergravity (3G), D. melanogaster flew in much similar way as 1G control, but it tended to fly somewhat randomly after the recovery from the hypergravity. D. melanogaster exhibits extraordinary maneuverability, relying on feedback from visual as well as mechanical sensation. Our results strongly suggest that gravity plays important roles for performing the robust flight maneuver, and therefore that the sensory systems for terrestrial gravity should be functional during the flight of D. melanogaster., 著者人数: 14人, Number of authors: 14, 資料番号: AA0065129043

The problem of a block repeatedly sliding, jumping and being conveyed inside a vibrating spatial tube is studied. Analytical models and equations are established in considering three kinds of motion states : relative sliding motion, flying motion and the bumping process. Precise investigations are carried out for the inclined frictions with component velocities and for oblique impact, which are seldom discussed thoroughly and are easily misinterpreted. The detailed motion of the entire response, called the ""subperiodic motion"", is revealed through numerical solutions. Fundamental effects of some basic parameters on the motion of the system are discussed. Appropriate ranges for both the frequency and the amplitudes of vibration are discovered to be very narrow. Experimental studies confirmed the theoretical analyses presented.