• Title/Summary/Keyword: 4bar linkage

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Aerodynamic Characteristics of an Insect-type Flapping Wings (곤충 모방 플래핑 날개의 공력 특성)

  • Han, Jong-Seob;Chang, Jo-Won;Choi, Hae-Cheon;Kang, In-Mo;Kim, Sun-Tae
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2007.11a
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    • pp.311-314
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    • 2007
  • Aerodynamic characteristics of an insect-type flapping wings were carried out to obtain the design parameters of Micro Hovering Air Vehicle. A pair of wing model was scaled up about 200 times and applied two pairs of 4-bar linkage mechanism to mimic the wing motion of a fruit fly(Drosophila). To verify the Weis-Fogh mechanism, a pair of wings revolved on the 'Delayed Rotation'. Lift and drag were measured in conditions of the Reynolds number based on wing tip velocity of about 1,200 and the maximum angle of attack of 40$40^{\circ}$. Inertia forces of a wing model were also measured by using a 99.98% vacuum chamber and subtracted on measured data in air. In the present study, high lift effect of Weis-Fogh mechanism was appeared in the middle of upstroke motion.

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Miniature Jumping Robot Using SMA Coil Actuators and Composite Materials (형상기억합금 코일 구동기와 복합재를 이용한 소형 도약 로봇 설계 및 제작)

  • Jung, Sun-Pill;Koh, Je-Sung;Jung, Gwang-Pil;Cho, Kyu-Jin
    • The Journal of Korea Robotics Society
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    • v.8 no.2
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    • pp.136-142
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    • 2013
  • In nature, many small insects are using jumping as a survival strategy. Among them, fleas jump in a unique method. They use an elastomer, 'Resilin', an extensor muscle and a trigger muscle. By contracting the extensor muscle, the elastic energy, that makes a flea to jump, is stored in the resilin. After storing energy, the trigger muscle begins contracting and pulling the extensor muscle. When the extensor muscle crosses the rotational joint, direction of torque generated from the extensor muscle reverses, 'torque reversal mechanism'. Simultaneously, the elastic energy stored in the resilin releases rapidly and is converted into the kinetic energy. It makes a flea to jump 150 times its body length. In this paper, miniaturized jumping robot using flea-inspired catapult mechanism is presented. This mechanism is based on the 4-bar linkage and the reversal joint and is actuated by Shape Memory Alloy (SMA) coiled springs describing the flea's muscle. The robot prototype is fabricated by SCM process using glass fiber prepregs and a sheet of polyimide film. The prototype is 20mm link length, 34mm width and 2.0g weight and can jump 103cm.