Flight Characteristics of Flapping Wing Miniature Air Vehicles With “Figure-8” Spherical Motion

2009 ◽  
Author(s):  
Mohamed B. Trabia ◽  
Woosoon Yim ◽  
Zohaib Rehmat ◽  
Jesse Roll
Keyword(s):  
Mathematical Model ◽  
Wind Tunnel ◽  
Experimental Testing ◽  
Flapping Wing ◽  
Dynamic Stall ◽  
Wind Tunnel Testing ◽  
Servo Motor ◽  
Aerodynamic Forces ◽  
Flapping Motion ◽  
Spherical Motion

Hummingbirds and some insects exhibit “Figure-8” flapping motion that allows them to go through a variety of maneuvers including hovering. Understanding the flight characteristics of Figure-8 flapping motion can potentially yield the foundation of flapping wing UAVs that can experience similar maneuverability. In this paper, a mathematical model of the dynamic and aerodynamic forces associated with Figure-8 motion generated by a spherical four bar mechanism is developed. For validation, a FWMAV prototype with the wing attached to a coupler point and driven by a DC servo motor is created for experimental testing. Wind tunnel testing is conducted to determine the coefficients of flight and the effects of dynamic stall. The wing is driven at speeds up to 12.25 Hz with results compared to that of the model. The results indicate good correlation between mathematical model and experimental prototype.

Design of “Figure-8” Spherical Motion Flapping Wing for Miniature UAV

2009 ◽  
Author(s):  
Zohaib Rehmat ◽  
Jesse Roll ◽  
Joon S. Lee ◽  
Woosoon Yim ◽  
Mohamed B. Trabia
Keyword(s):  
Experimental Testing ◽  
Flapping Wing ◽  
Servo Motor ◽  
Flapping Motion ◽  
Experimental Prototype ◽  
Wing Motion ◽  
Air Vehicle ◽  
Spherical Motion

Hummingbirds and some insects exhibit a “Figure-8” flapping motion, which allows them to undergo variety of maneuvers including hovering. It is therefore desirable to have miniature air vehicle (FWMAV) with this wing motion. This paper presents a design of a flapping-wing for FWMAV that can mimic “Figure-8” motion using a spherical four bar mechanism. In the proposed design, the wing is attached to a coupler point on the mechanism, which is driven by a DC servo motor. A prototype is fabricated to verify that the design objectives are met. Experimental testing was conducted to determine the validity of the design. The results indicate good correlation between model and experimental prototype.

Design of a Bio-Inspired Spherical Four-Bar Mechanism for Flapping-Wing Micro Air-Vehicle Applications

2008 ◽  
Author(s):  
Matt McDonald ◽  
Sunil K. Agrawal
Keyword(s):  
Three Dimensional ◽  
Micro Air Vehicles ◽  
Aerodynamic Performance ◽  
Flapping Wing ◽  
Micro Air Vehicle ◽  
Aerodynamic Forces ◽  
Flapping Motion ◽  
Wing Motion ◽  
Air Vehicle ◽  
Flapping Mechanism

Design of flapping-wing micro air-vehicles presents many engineering challenges. As observed by biologists, insects and birds exhibit complex three-dimensional wing motions. It is believed that these unique patterns of wing motion create favorable aerodynamic forces that enable these species to fly forward, hover, and execute complex motions. From the perspective of micro air-vehicle applications, extremely lightweight designs that accomplish these motions of the wing, using just a single, or a few actuators, are preferable. This paper presents a method to design a spherical four-bar flapping mechanism that approximates a given spatial flapping motion of a wing, considered to have favorable aerodynamics. A spherical flapping mechanism was then constructed and its aerodynamic performance was compared to the original spatially moving wing using an instrumented robotic flapper with force sensors.

Investigating pitching moment stall through dynamic wind tunnel test

2019 ◽  
Vol 234 (2) ◽  
pp. 267-279
Author(s):  
Alessandro Pontillo ◽  
Sezsy Yusuf ◽  
Guillermo Lopez ◽  
Dominic Rennie ◽  
Mudassir Lone
Keyword(s):  
Parameter Estimation ◽  
Wind Tunnel ◽  
Wind Tunnel Test ◽  
Angular Acceleration ◽  
Direct Calculation ◽  
Dynamic Stall ◽  
Nonlinear Behaviour ◽  
Wind Tunnel Testing ◽  
Pitching Moment ◽  
Heave Motion

Experimental characterisation of aircraft dynamic stall can be a challenging and complex system identification activity. In this article, the authors present a method that combines dynamic wind tunnel testing with parameter estimation techniques to study the nonlinear pitching moment dynamics of a 1/12 scale Hawk model undergoing moment stall. The instrumentation setup allows direct calculation of angular acceleration terms, such as pitch acceleration, and avoids post-processing steps involving differentiation of signals. Data collected from tests, carried out at 20 m/s and 30 m/s, are used for a brief aerodynamic analysis of the observed stall hysteresis. Then an output-error-based parameter estimation process is used to parameterise dynamic stall models and furthermore, illustrate that in a scenario where the model's heave motion is constrained. The observed nonlinear behaviour arises from the nonlinear angle of attack and linear pitch rate components.

Modelling and Simulation of a Flapping Wing Mechanism Driven by a Brushless Servo Motor

2010 ◽  
Author(s):  
Jin Xie ◽  
Yong Chen
Keyword(s):  
Nonlinear Dynamic System ◽  
Input Voltage ◽  
Flapping Wing ◽  
Phase Lag ◽  
Servo Motor ◽  
Flapping Motion ◽  
Runge Kutta Method ◽  
Air Vehicle ◽  
And Control ◽  
The Relationship

Flapping wing mechanism is designed to generate flapping motion for a micro air vehicle. Some issues concerning with the design and control of flapping wing mechanism are discussed in this paper. Firstly the problem of phase-lag between two wings is treated. To eliminate phase-lag, a method of modifying the design is proposed. Then, motion controlling of a flapping wing mechanism by means of changing the voltage inputted to servo motor is studied. Based on Lagrange’s formulation and Kirchhoff’s voltage law, motion equation for a servo motor coupled to flapping wing mechanism is established. Fourth-order Runge-Kutta method is employed to integrate this equation. For the purpose of finding the relationship between the flapping motion and the input voltage, a response diagram obtained from simulation of the system is utilized. A crucial voltage VC is obvious in the response diagram. If the input voltage is lower than VC, the mechanism will settle at its fixed point, only when the input voltage is higher than VC, can the mechanism work in order. Both to find all fixed points and to analyze their stability for a complex nonlinear dynamic system are difficult tasks. A numerical method to deal with these difficulties is proposed. The results of simulation also show that the flapping frequency increases with the increasing of input voltage provided that the input voltage is higher than VC.

Design and Analysis of Flapping Wing

2011 ◽  
Vol 110-116 ◽  
pp. 3495-3499
Author(s):  
G.C. Vishnu Kumar ◽  
M. Rahamath Juliyana
Keyword(s):  
Experimental Data ◽  
Flapping Wing ◽  
Micro Air Vehicle ◽  
Flapping Wings ◽  
Visualization Technique ◽  
Aerodynamic Forces ◽  
Flapping Motion ◽  
Smoke Flow ◽  
Air Vehicle ◽  
Lift And Drag

This paper the optimum wing planform for flapping motion is investigated by measuring the lift and drag characteristics. A model is designed with a fixed wing and two flapping wings attached to its trailing edge. Using wind tunnel tests are conducted to study the effect of angle of attack (smoke flow visualization technique). The test comprises of measuring the aerodynamic forces with flapping motion and without it for various flapping frequencies and results are presented. It can be possible to produce a micro air vehicle which is capable of stealthy operations for defence requirements by using these experimental data.

Modified Unsteady Vortex Lattice Method for Aerodynamics of Flapping Wing Models

2015 ◽  
Author(s):  
Anh Tuan Nguyen ◽  
Jae-Hung Han
Keyword(s):  
Vortex Lattice ◽  
Micro Air Vehicles ◽  
Flapping Wing ◽  
Preliminary Design ◽  
Aerodynamic Forces ◽  
Lattice Method ◽  
Real Motion ◽  
Flapping Motion ◽  
The Real ◽  
Vortex Lattice Method

Motivated by extensive possible applications of flapping-wing micro-air vehicles (MAVs) to various different areas, there has been an increasing amount of research related to this issue. In the stage of preliminary studies, one of the most important tasks is to predict the aerodynamic forces generated by the flapping motion. Studying aerodynamics of insects is an efficient way to approach the preliminary design of flapping-wing MAVs. In this paper, a modified version of an Unsteady Vortex Lattice Method (UVLM) is developed to compute aerodynamic forces appearing in flapping-wing models. A hawkmoth-like wing with kinematics based on the real motion is used for the simulations in this paper.

Sign in / Sign up

Export Citation Format

Share Document