A Review of Biomimetic Air Vehicle Research: 1984-2014

Biomimetic air vehicles (BAV) are a class of unmanned aircraft that mimic the flapping wing kinematics of flying organisms (e.g. birds, bats, and insects). Research into BAV has rapidly expanded over the last 30 years. In this paper, we present a comprehensive bibliometric review of engineering and biology journal articles that were published on this subject between 1984 and 2014. These articles are organized into five topical categories: aerodynamics, guidance and control, mechanisms, structures and materials, and system design. All of the articles are compartmented into one of these categories based on their primary focus. Several aspects of these articles are examined: publication year, number of citations, journal, authoring organization and country, non-academic funding sources, and the flying organism focused upon for bio-mimicry. This review provides useful information on the state of the art of BAV research and insight on potential future directions. Our intention is that this will serve as a resource for those already engaged in BAV research and enable insight that promotes further research interest

An experimental study of the elastic properties of dragonfly-like flapping wings for use in Biomimetic Micro Air Vehicles (BMAV)

This article studies the elastic properties of several biomimetic micro air vehicle (BMAV) wings that are based on a dragonfly wing. BMAVs are a new class of unmanned micro-sized air vehicles that mimic the flapping wing motion of flying biological organisms (e.g., insects, birds, and bats). Three structurally identical wings were fabricated using different materials: acrylonitrile butadiene styrene (ABS), polylactic acid (PLA), and acrylic. Simplified wing frame structures were fabricated from these materials and then a nanocomposite film was adhered to them which mimics the membrane of an actual dragonfly. These wings were then attached to an electromagnetic actuator and passively flapped at frequencies of 10–250 Hz. A three-dimensional high frame rate imaging system was used to capture the flapping motions of these wings at a resolution of 320 pixels × 240 pixels and 35000 frames per second. The maximum bending angle, maximum wing tip deflection, maximum wing tip twist angle, and wing tip twist speed of each wing were measured and compared to each other and the actual dragonfly wing. The results show that the ABS wing has considerable flexibility in the chordwise direction, whereas the PLA and acrylic wings show better conformity to an actual dragonfly wing in the spanwise direction. Past studies have shown that the aerodynamic performance of a BMAV flapping wing is enhanced if its chordwise flexibility is increased and its spanwise flexibility is reduced. Therefore, the ABS wing (fabricated using a 3D printer) shows the most promising results for future applications

Structural dynamic characterization of biobased micro aerial vehicles / Rubentheren Viyapuri

Micro Aerial Vehicle, MAVs is latest generation of aircraft inspired from micro natural fliers. Mimicking those fliers need extensive research and fine tools. Besides flight dynamics, propulsion system and structures integrity, wings plays a very important role in creating lifts and vortices to make a successful liftoff. MAV wings subjected to enormous level of mechanical stress due to flapping frequencies and posses a wide area to scope air. With all those bombardment, MAV wings should perform in a harmonize way with the stress being generated, yet the wing should be keep at minimum weight as possible. This research work is intended to investigate the mechanical properties of thin film PVA with biomimetic units drawn on the surface on the film for the application of MAV wing membrane. Biomimetic units grid, striation, spot were drawn on the surface of PVA thin film by means of heated geometry cutter. A control specimen named no pattern were then compared with the biomimetic specimen in terms of tensile testing for mechanical properties, DMA analysis for viscoelastic properties and DSC analysis for percentage of crystallinity. Result shows grid specimen exhibit highest level of mechanical properties and viscoelastic properties. This is due to the percentage of crystallinity formed in grid was the highest and thus elevate the mechanical properties of PVA thin film. Heated geometry cutter creates localized heat to melt the polymer and solidify quickly which crystallize the edge of the drawn pattern and in turn improve the mechanical properties when compared to pure PVA thin film

Experimental analysis of artificial dragonfly wings using black graphite and fiberglass for use in Biomimetic Micro Air Vehicles (BMAVs)

This article examines the suitability of two different materials which are black graphite carbon fiber and red pre-impregnated fiberglass from which to fabricate artificial dragonfly wing frames. These wings could be of use in Biomimetic Micro Aerial Vehicles (BMAV). BMAV are a new class of unmanned micro-sized air vehicles that mimic flying biological organisms. Insects, such as dragonflies, possess corrugated and complex vein structures that are difficult to mimic. Simplified dragonfly wing frames were fabricated from these materials and then a nano-composite film was adhered to them, which mimics the membrane of an actual dragonfly. Experimental analysis of these results showed that although black graphite carbon fiber and red pre-impregnated fiberglass offer some structural advantages, red pre-impregnated fiberglass was a less preferred option due to its warpage and shrinking effects. Black graphite carbon fiber with its high load bearing capability is a more suitable choice for consideration in future BMAV applications

Procesessing and Analysis of Chitosan Nanocomposites Reinforced with Chitin Whiskers and Tannic Acid as a Crosslinker

Chitosan film reinforced with nano-sized chitin whiskers and crosslinked using tannic acid was synthesized by the casting–vaporation method. The mechanical and physicochemical properties of several film samples (consisting of different ratio of chitin and tannic acid) were compared with neat chitosan. Tensile tests show that the addition of chitin improves the nanocomposite films mechanical properties up to 137% compared to neat chitosan, but this is slightly degraded when tannic acid is introduced. However, tannic acid and chitin whisker content greatly reduced moisture content by 294% and water solubility by 13%. Transmission electron microscopy (TEM) and Fourier-transform-infrared spectroscopy (FTIR) were used to investigate the morphology and molecular interaction of film. X-ray diffraction results indicated that the samples with chitin whiskers had a more rigid structure. The addition of tannic acid changed the structure into an anhydrous crystalline conformation when compared to neat chitosan film

Physical and Chemical Reinforcement of Chitosan Film Using Nanocrystalline Cellulose and Tannic Acid

Chitosan film with nanocrystalline cellulose (NCC) as a physical reinforcement and tannic acid as a chemical crosslinker was prepared by the casting evaporation method. The objective was to improve its mechanical properties, reduce its moisture content and solubility, and maintain its biodegradability. This was done to examine its potential suitability as an ultra-lightweight wing membrane for a future biomimetic micro air vehicle. Different contents of nanofiller material and tannic acid were added to a chitosan matrix and comparisons were made with neat chitosan film. Mechanical test shows that the addition of NCC into the chitosan matrix improves the tensile strength by 69.8 % compared to neat chitosan. Insertion of tannic acid to the nanocomposite film further improves the tensile strength by 82.6 %. These reinforcement materials also reduce the moisture content up to 73.5 % and water solubility to 67.9 %. Morphological studies were carried out using transmission electron microscopy (TEM), scanning electron microscopy (SEM) and an ultraviolet–visible spectrophotometer. The TEM images revealed the presence of nano-sized cellulose particles with high aspect ratios (average of 20.9). SEM images were examined to reveal the dispersion level of NCC and the effects of tannic acid in the film. Fourier-transform-infrared spectroscopy imagery was used to define the interaction of the molecules. X-ray diffraction analysis confirms that the addition of NCC increases the presence of crystalline structures in the film, which makes it more rigid. The addition of tannic acid changed the structure into an anhydrous crystalline conformation, when compared to neat chitosan film

Processing and analysis of chitosan nanocomposites reinforced with chitin whiskers and tannic acid as a crosslinker

Chitosan film reinforced with nano-sized chitin whiskers and crosslinked using tannic acid was synthesized by the casting-vaporation method. The mechanical and physicochemical properties of several film samples (consisting of different ratio of chitin and tannic acid) were compared with neat chitosan. Tensile tests show that the addition of chitin improves the nanocomposite films mechanical properties up to 137% compared to neat chitosan, but this is slightly degraded when tannic acid is introduced. However, tannic acid and chitin whisker content greatly reduced moisture content by 294% and water solubility by 13%. Transmission electron microscopy (TEM) and Fourier-transform-infrared spectroscopy (FTIR) were used to investigate the morphology and molecular interaction of film. X-ray diffraction results indicated that the samples with chitin whiskers had a more rigid structure. The addition of tannic acid changed the structure into an anhydrous crystalline conformation when compared to neat chitosan film. (C) 2014 Elsevier Ltd. All rights reserved

Static strength analysis of dragonfly inspired wings for biomimetic micro aerial vehicles

AbstractThis article examines the suitability of fabricating artificial, dragonfly-like, wing frames from materials that are commonly used in unmanned aircraft (balsa wood, black graphite carbon fiber and red prepreg fiberglass). Wing frames made with Type 321 stainless steel are also examined for comparison. The purpose of these wings is for future use in biomimetic micro aerial vehicles (BMAV). BMAV are a new class of unmanned micro-sized aerial vehicles that mimic flying biological organisms (like flying insects). Insects, such as dragonflies, possess corrugated and complex vein structures that are difficult to mimic. Simplified dragonfly-like wing frames were fabricated from these materials and then a nano-composite film was adhered to them, which mimics the membrane of an actual dragonfly. Finite element analysis simulations were also performed and compared to experimental results. The results showed good agreement (less than 10% difference for all cases). Analysis of these results shows that stainless steel is a poor choice for this wing configuration, primarily because of the aggressive oxidation observed. Steel, as well as balsa wood, also lacks flexibility. In comparison, black graphite carbon fiber and red prepreg fiberglass offer some structural advantages, making them more suitable for consideration in future BMAV applications