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An analysis of the kinematics of a flapping membrane wing using experimental kinematic data is presented. This motion capture technique tracks the positon of the retroreflective marker(s) placed on the left wing of a 1.3-m-wingspan ornithopter. The time-varying three-dimensional data of the wing kinematics were recorded for a single frequency. The wing shape data was then plotted on a two-dimensional plane to understand the wing dynamic behaviour of an ornithopter. Specifically, the wing tip path, leading edge bending, wing membrane shape, local twist, stroke angle and wing velocity were analyzed. As the three characteristic angles can be expressed in the Fourier series as a function of time, the kinematics of the wing can be computationally generated for the aerodynamic study of flapping flight through the Fourier coefficients presented. Analysis of the ornithopter wing showed how the ornithopter closely mimics the flight motions of birds despite several physical limitations.
Matthew Ng Rongfa; Teppatat Pantuphag; Sutthiphong Srigrarom. Analysis of Kinematics of Flapping Wing UAV Using OptiTrack Systems. Aerospace 2016, 3, 23 .
AMA StyleMatthew Ng Rongfa, Teppatat Pantuphag, Sutthiphong Srigrarom. Analysis of Kinematics of Flapping Wing UAV Using OptiTrack Systems. Aerospace. 2016; 3 (3):23.
Chicago/Turabian StyleMatthew Ng Rongfa; Teppatat Pantuphag; Sutthiphong Srigrarom. 2016. "Analysis of Kinematics of Flapping Wing UAV Using OptiTrack Systems." Aerospace 3, no. 3: 23.
In this paper, an ornithopter prototype that mimics the flapping motion of bird flight is developed, and the lift and thrust generation characteristics of different wing designs are evaluated. This project focused on the spar arrangement and material used for the wings that could achieves improved performance. Various lift and thrust measurement techniques are explored and evaluated. Various wings of insects and birds were evaluated to understand how these natural flyers with flapping wings are able to produce sufficient lift to fly. The differences in the flapping aerodynamics were also detailed. Experiments on different wing designs and materials were conducted and a paramount wing was built for a test flight. The first prototype has a length of 46.5 cm, wing span of 88 cm, and weighs 161 g. A mechanism which produced a flapping motion was fabricated and designed to create flapping flight. The flapping flight was produced by using a single motor and a flexible and light wing structure. A force balance made of load cell was then designed to measure the thrust and lift force of the ornithopter. Three sets of wings varying flexibility were fabricated, therefore lift and thrust measurements were acquired from each different set of wings. The lift will be measured in ten cycles computing the average lift and frequency in three different speeds or frequencies (slow, medium and fast). The thrust measurement was measure likewise but in two cycles only. Several observations were made regarding the behavior of flexible flapping wings that should aid in the design of future flexible flapping wing vehicles. The wings angle or phase characteristic were analyze too and studied. The final ornithopter prototype weighs only 160 g, has a wing span of 88.5 cm, that could flap at a maximum flapping frequency of 3.869 Hz, and produce a maximum thrust and lift of about 0.719 and 0.264 N respectively. Next, we proposed resonance type flapping wing utilizes the near resonance phenomenon of a two-degree of freedom elastic system, that is, the wing is supported by the springs for flapping and feathering motions. Being oscillated close to the resonance frequency of the system, only by the torque in flapping motion, the amplitude gained is a few times higher than that of normal case. The first prototype was made from acrylic using a laser cutting machine. The wings were made up of carbon rods and kite material Ripstop. First test showed that the wings were too heavy for the mechanism to work. The third prototype was a smaller single gear crank design which was fabricated using a 3D printer. Initial test proved that the second prototype could withstand the high frequency flapping and near resonance amplitude as designed. With remote control, the third prototype was able to take off, climb, cruise and land in flapping mode successfully.
Sutthiphong Srigrarom; Woei-Leong Chan. Ornithopter Type Flapping Wings for Autonomous Micro Air Vehicles. Aerospace 2015, 2, 235 -278.
AMA StyleSutthiphong Srigrarom, Woei-Leong Chan. Ornithopter Type Flapping Wings for Autonomous Micro Air Vehicles. Aerospace. 2015; 2 (2):235-278.
Chicago/Turabian StyleSutthiphong Srigrarom; Woei-Leong Chan. 2015. "Ornithopter Type Flapping Wings for Autonomous Micro Air Vehicles." Aerospace 2, no. 2: 235-278.