Development of a Flapping Wing Mechanism
Oliver Breitenstein
Development of a Flapping Wing Mechanism
Semester Project
Autonomous Systems Lab (ASL) Swiss Federal Institute of Technology (ETH) Zurich
Supervision Dr. Samir Bouabdallah, Stefan Leutenegger and Prof. Dr. Roland Siegwart
Spring Semester 2009
Contents
Abstract Acknowledgements 1 Introduction 2 Review 2.1 Aerodynamics of flapping wings . 2.1.1 Wagner Effect . . . . . . . 2.1.2 Leading edge vortex . . . 2.1.3 Clap and fling mechanism 2.1.4 Rotational lift . . . . . . . 2.1.5 Wing-wake interactions . 2.1.6 Lift force . . . . . . . . . 2.2 Flapping wings in nature . . . . 2.2.1 Insects . . . . . . . . . . . 2.2.2 Hummingbirds . . . . . . 2.2.3 Bats . . . . . . . . . . . . 2.2.4 Birds . . . . . . . . . . . . 2.3 Summary . . . . . . . . . . . . . 3 Concepts 3.1 General Considerations . . . . . 3.1.1 Objective characteristics 3.1.2 Flight control . . . . . . 3.1.3 Actuator . . . . . . . . 3.2 Concepts for wing flapping . . 3.2.1 Concept A . . . . . . . 3.2.2 Concept B . . . . . . . . 3.2.3 Concept C . . . . . . . 3.2.4 Concept D . . . . . . . 3.3 Concepts for wing pitching . . 3.3.1 Active pitching . . . . . 3.3.2 Passive pitching . . . . 4 Evaluation 4.1 Evaluation of concepts . . . . 4.1.1 Criteria . . . . . . . . 4.1.2 Flapping concepts . . 4.1.3 Pitching concepts . . . 4.2 Expected weight . . . . . . . 4.3 Expected power consumption iii iv 1 3 3 3 3 4 5 6 6 7 7 10 13 16 17 21 21 21 22 22 23 23 24 25 29 29 29 32 35 35 35 36 36 37 38
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Development of a Flapping Wing Mechanism
Semester Project
Autonomous Systems Lab (ASL) Swiss Federal Institute of Technology (ETH) Zurich
Supervision Dr. Samir Bouabdallah, Stefan Leutenegger and Prof. Dr. Roland Siegwart
Spring Semester 2009
Contents
Abstract Acknowledgements 1 Introduction 2 Review 2.1 Aerodynamics of flapping wings . 2.1.1 Wagner Effect . . . . . . . 2.1.2 Leading edge vortex . . . 2.1.3 Clap and fling mechanism 2.1.4 Rotational lift . . . . . . . 2.1.5 Wing-wake interactions . 2.1.6 Lift force . . . . . . . . . 2.2 Flapping wings in nature . . . . 2.2.1 Insects . . . . . . . . . . . 2.2.2 Hummingbirds . . . . . . 2.2.3 Bats . . . . . . . . . . . . 2.2.4 Birds . . . . . . . . . . . . 2.3 Summary . . . . . . . . . . . . . 3 Concepts 3.1 General Considerations . . . . . 3.1.1 Objective characteristics 3.1.2 Flight control . . . . . . 3.1.3 Actuator . . . . . . . . 3.2 Concepts for wing flapping . . 3.2.1 Concept A . . . . . . . 3.2.2 Concept B . . . . . . . . 3.2.3 Concept C . . . . . . . 3.2.4 Concept D . . . . . . . 3.3 Concepts for wing pitching . . 3.3.1 Active pitching . . . . . 3.3.2 Passive pitching . . . . 4 Evaluation 4.1 Evaluation of concepts . . . . 4.1.1 Criteria . . . . . . . . 4.1.2 Flapping concepts . . 4.1.3 Pitching concepts . . . 4.2 Expected weight . . . . . . . 4.3 Expected power consumption iii iv 1 3 3 3 3 4 5 6 6 7 7 10 13 16 17 21 21 21 22 22 23 23 24 25 29 29 29 32 35 35 35 36 36 37 38
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