• 한국항공우주학회지
• /
• 제39권10호
• /
• pp.905-911
• /
• 2011

초소형 작동기 기술의 발전과 함께, 초소형 플랩핑 날개짓 비행체 개발 연구가 활발히 진행중이다. 본 연구에서는 경계요소법을 사용하여 히브진동운동하는 3차원 날개의 운동학적 매개변수인 진동 주파수 및 진폭과 기하학적 변수인 테이퍼 및 종횡비의 변화에 따른 양력 및 추력 특성을 연구했다. 날개짓 주파수가 1Hz 보다 작은 경우 진폭과 무관하게 양력이 발생하지 않았다. 추력계수 값은 날개짓 주파수와 히빙진폭이 클수록 값의 크기가 증가했다. 테이퍼 비와 종횡비가 큰 날개일수록 양력 및 추력 값이 크게 나타났다. 향후 피칭 및 플랩핑 운동 날개의 공력특성변화에 대한 연구를 수행할 예정이다.

• 한국항공운항학회:학술대회논문집
• /
• 한국항공운항학회 2004년도 추계학술발표대회 논문집
• /
• pp.104-107
• /
• 2004

• 대한기계학회:학술대회논문집
• /
• 대한기계학회 2004년도 춘계학술대회
• /
• pp.1993-1998
• /
• 2004

The present study was carried out to develop highly efficient RC ornithopter 'Songgolmae' powered by motor and battery. Designed electric ornithopter weighs 277 grams and has 3 channels radio control. 1t runs on an electric motor by a lithium polymer battery and has a gear ratio of about $75{\sim}95$ to 1 to flap its 88 cm wingspan. The aerodynamic performance of the ornithopter, applied to a flapping motion only, was validated by flight tests. Flight times have exceeded 23 minutes until the battery was used up. The flight test results indicate that the ornithopter developed here has sufficient thrust to propel itself in a forward flight. From the economical point of view and the handling of the RC ornithopter, it can be said that the developed robot ornithopter is an effective RC ornithopter. This radio controlled ornithopter flies its way high into the sky just like a real bird flies.

• 한국항공운항학회:학술대회논문집
• /
• 한국항공운항학회 2004년도 추계학술발표대회 논문집
• /
• pp.100-103
• /
• 2004

• 한국항공우주학회지
• /
• 제45권3호
• /
• pp.173-179
• /
• 2017

본 논문에서는 모션캡쳐 카메라를 사용한 실험을 통해 날갯짓 비행체의 주 날개, 꼬리날개 구동기 특성 분석에 대하여 기술하였다. 실험은 빛이 차단된 실내에서 진행되었고 지그에 기체를 고정하여 날갯짓으로 인한 영향을 줄였다. 주 날개와 꼬리날개 끝단에 마커를 부착하였고 모션캡쳐 카메라는 입력 신호에 대한 각각의 반응을 측정한다. 실험 결과 주 날개는 날갯짓의 주파수에 따라 진폭이 변하는 경향을 보였고, Modified Strip Theory에 실험 결과와 비행체 제원을 적용하여 양력 및 추력 발생 시뮬레이션을 구현 하였다. 꼬리날개는 종 횡축별로 스텝 신호를 인가하여 이에 따른 결과를 2차 전달함수 형태로 정의하였고, 각 축별로 구동기의 구조 차이로 인하여 최종 응답시간, 오버슈트, 최대값 등에서 차이를 나타내는 것을 확인하였다.

• 한국항공운항학회지
• /
• 제11권1호
• /
• pp.5-16
• /
• 2003

The present study was carried out to develop highly efficient RC ornithopter 'Songgolmae' powered by motor and battery. Designed electric ornithopter, which has the dimension of O.88m(W)${\times}$0.56m(L)${\times}$0.15m(H), is smaller than a conventional ornithopter. This ornithopter weighs 277 grams and has 3 channels radio control. It runs on an electric motor by a lithium polymer battery and has a gear ratio of about 75${\sim}$95 to 1 to flap its 88 cm wingspan. The aerodynamic performance of the ornithopter, applied to a flapping motion only, was validated by flight tests. Flight times have exceeded 23 minutes until the battery was used up. The flight test results indicate that the ornithopter developed here has sufficient thrust to propel itself in a forward flight. From the economical point of view and the handling of the RC ornithopter, it can be said that the developed robot ornithopter is an effective RC ornithopter. This robot ornithopter flies its way high into the sky just like a real bird flies. The robot ornithopter is used for a wide range of missions.

• 한국항공우주학회지
• /
• 제33권10호
• /
• pp.82-92
• /
• 2005

본 연구는 중량 20그램의 무선조종 초소형 날갯짓 비행체를 개발하기 위하여 수행되었다. 본 날갯짓 비행체는 3채널 방식의 무선조종을 사용하였고, 리튬 폴리머 배터리로 두 개의 DC 페이저 모터를 구동하여 35cm 크기의 날개로 날 수 있도록 하였다. 플래핑 운동만 적용된 날갯짓 비행체의 성능은 비행시험으로 입증되었다. 비행시험 결과는 비행체의 추진에 필요한 충분한 추력이 발생하도록 개발되었다는 것을 나타낸다.

• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 2003년도 춘계학술대회 논문집
• /
• pp.709-712
• /
• 2003

The existing technical limitation makes engineer imitate nature to solve engineering problems. Recently Micro Air Vehicle(MAV) imitating the mechanism of birds or insects is being developed. Especially Ultra Flite supported by DARPA is studying hummingbird aerodynamics to relate that information to MAV. To drive MAV bender piezoelectric(PZT) actuators are used due to the convinience of control and the small size. But the displacement of the PZT actuators are very small, and the wing driving mechanism which amplifies the stroke generated by the PZT actuators has constraints in design and manufacture because of the small dimension. In this paper a wing design concept and a efficient driving mechanism are proposed. Electroactive polymers(EAPs) are used as wing mechanism actuators. Using OpenGL the mechanisms are simulated graphically. Also a prototype actuator is being developed and verified by digital Mockup with CATIA. Basic kinematics of the mechanism is studied.

• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 1997년도 추계학술대회 논문집
• /
• pp.684-688
• /
• 1997

The human species has been able to fly for about a century - with the help of aircraft of various kinds. Recently. air vehicles which are like an insect or a bird with flapping wings have been appeared, although many of them are experimental flight vehicle. However, the rubber-powered flapping vehicle is put to practical use such as toy, which flies for some seconds. In this paper, we analyze and evaluate above the rubber-powered flight vehicle using axiomatic design and will present new four flapping wing model.

• 한국군사과학기술학회지
• /
• 제10권1호
• /
• pp.33-43
• /
• 2007

Using the more common conventional chordwise aerodynamic approach, flapping a flat plate wing with zero degree chordwise pitch angle of attack and no relative wind should not produce lift. However, in hover, with no forward relative velocity and zero degree chordwise pitch angle of attack, flapping flat plate wings does in fact produce lift. In the experiments peformed for this paper, the flapping motion is considered pure(downstroke and upstroke) with no flapping stroke plane inclination angle. No changes in chordwise pitch angle are made. The total force is measured using a force transducer and the net aerodynamic force is determined from this measured total force by subtracting the experimentally determined inertial contribution. These experiments were repeated at various flapping frequencies and for various wing planform sizes for flat plate wings. The trends in the aerodynamic lift variation found using a force transducer have nearly identical shape for various flapping frequencies and wing planform sizes.