Hybrid Drone with Flapping and Fixed Wings

ABSTRACT

As compared to twin-prop aircraft that fly forward, twin-prop tail-sitting micro-aircraft, such as Wintra One, can take off and land vertically in addition to the forward cruise. Yet, the aerodynamic efficiency of a propeller that was optimized to hover may not be optimal during a forward flight. This motivates us to revisit the biomimetic design to fuse the flexible flapping wings and fixed wings just like an eagle or albatross to improve the lift and thrust generation for micro tail sitters. The thrust-generating plane of the flexible wing can self-pitch to adapt to the wind’s streamline. Our flight test shows that the fixed wing does not interfere with the flapping wings for the thrust generation during hover, it provides extra lift when flying forwards or turning. Given the thrust to hover, a transit to forwards flight helps the micro-tail sitter make a climb. This encouraging result warrants further research and development of the hybrid drone.

Mr. Huang Chih Kai is pursuing his MSc study in the Graduate Degree Program of Robotics at National Yang Ming Chiao Tung University, Taiwan. During his study, he has researched and developed a Hybrid drone with flapping and fixed wings.

Tunable Double-layer Design of Acoustic Resonant Absorber Panels

ABSTRACT

Rail and vehicle noises are annoying to urban residents. Noise barriers made of thin slot panels help reflect and insulate the noise but does not absorb much of it given the thin porous absorbers embedded. Micro-perforated panels have been recently developed to make absorbent sound barriers free from porous material but costs more to manufacture. As an inexpensive alternative, micro-slit acoustic panel absorbers stand a chance to be optimized to absorb medium-to-low frequency noise. Plastic micro-slit panels are transparent and lightweight for widespread deployment. In this study, we propose the lamination of micro-slit panels with an inexpensive plastic film to make a double-layer resonant absorber panel that can better tolerate machining errors. The spacing between this plastic film and micro-slit panel can be optimally adjusted to shift the absorption spectrum to target and attenuate the varying peak of noise.

Mr. Wu Chih Chun is pursuing his MSc study in Mechanical Engineering at National Yang Ming Chiao Tung University, Taiwan. During his study, he has researched and developed self-clearable electro-adhesive pads suitable for application to robotic grippers and tunable acoustic device.