Design and characterisation of bio-inspired thorax for flapping-wing robotfly

Insects are impressive natural flyers. They fly with high agility and maneuverability by flapping their wings. Emulating their flight capability and flight mechanisms may provide a good start in the design of a micro air vehicle (MAV). In a NTU Undergraduate Research Experience on Campus (URECA) AY2008/2009 research by the author, a simple wing flapper was designed and developed with reference to the blueprint of the flight thorax of insects [16] [19]. The wing flapper design sought to overcome flight endurance and energy efficiency problems present in many MAV designs. Compliant mechanisms are used in substitute of revolute joints and gear systems in the design. The developed wing flapper consists of a thoracic frame structure as a flapping mechanism and a vibration motor as a driver. The initial Proof-of-Concept (POC) prototype demonstrates that the wing flappers are comparable to the insects in terms of the wingbeat frequency and body mass. However, the POC prototype was not designed with wings attached. In this NTU FYP-URECA AY2009/2010 research, fabrication and design problems faced in the previous research are addressed. Improved fabrication methods and design dimensions were implemented in the research. A simplified analytic model of the wing flapper was derived and used as a foundation for characterization experiments. The design parameters were varied in the experiments and the design rules for the wing flapper are identified. These design rules lead to the first flapping wing robotfly prototype since the inception of the wing flapper research. The robotfly prototype weighs only 3.68g, has a thoracic dimension of 12mm and has two 50mm wing attached. The robotfly prototype is demonstrated to be capable of flapping at an angle of 56o and 20.0Hz under experimental conditions. Although it is still not capable of flight, the robotfly prototype shows strong potentials for future development.Bachelor of Engineering (Aerospace Engineering