scholarly journals Performance Enhancement of Tilt-Body Micro Air Vehicle by Use of Orthotropic Laminated Proprotors

2016 ◽  
Vol 819 ◽  
pp. 585-590
Author(s):  
Fazila Mohd Zawawi ◽  
Peng Lv ◽  
Sebastien Prothin ◽  
Joseph Morlier ◽  
Emmanuel Benard ◽  
...  
Keyword(s):  
Structural Model ◽  
Performance Enhancement ◽  
Coupling Effect ◽  
Micro Air Vehicles ◽  
Element Model ◽  
Aerodynamic Model ◽  
Load Beam ◽  
Air Vehicle ◽  
Blade Element ◽  
Air Vehicles

A passive twist control is considered as an adaptive way to maximize the overall efficiency of a proprotor developed for convertible Micro Air Vehicles (MAV). In this paper, adaptation of the proprotor geometry in accordance to flight configurations is achieved by induced twist generated by the inherent structural coupling effect in anisotropic composite material and centrifugal force emanating from the tip load. Beam Finite Element Model based on Rotating Timoshenko Theory is used to predict structural loads, while Blade Element Momentum Theory is employed to predict the aerodynamic performance of adaptive proprotor as applied on Micro Air Vehicles (MAV). The iterative process of combination of aerodynamic model and structural model is used to compute the steady-state deformation of the flexible laminated proprotor blade due aerodynamic loads. Finally, the optimal design of lamina blade material is carried out to investigate the potential of flexible blade in the proprotorperformance enhancement.

scholarly journals Gust Mitigation of Micro Air Vehicles Using Passive Articulated Wings

2014 ◽  
Vol 2014 ◽  
pp. 1-10 ◽  
Author(s):  
Adetunji Oduyela ◽  
Nathan Slegers
Keyword(s):  
Experimental Validation ◽  
Micro Air Vehicles ◽  
Flight Test ◽  
Analytical Investigation ◽  
Micro Air Vehicle ◽  
Gust Alleviation ◽  
Air Vehicle ◽  
Lifting Surfaces ◽  
Gust Mitigation ◽  
Air Vehicles

Birds and insects naturally use passive flexing of their wings to augment their stability in uncertain aerodynamic environments. In a similar manner, micro air vehicle designers have been investigating using wing articulation to take advantage of this phenomenon. The result is a class of articulated micro air vehicles where artificial passive joints are designed into the lifting surfaces. In order to analyze how passive articulation affects performance of micro air vehicles in gusty environments, an efficient 8 degree-of-freedom model is developed. Experimental validation of the proposed mathematical model was accomplished using flight test data of an articulated micro air vehicle obtained from a high resolution indoor tracking facility. Analytical investigation of the gust alleviation properties of the articulated micro air vehicle model was carried out using simulations with varying crosswind gust magnitudes. Simulations show that passive articulation in micro air vehicles can increase their robustness to gusts within a range of joint compliance. It is also shown that if articulation joints are made too compliant that gust mitigation performance is degraded when compared to a rigid system.

Aeroelastic Analysis of Membrane Micro Air Vehicles

2009 ◽  
Author(s):  
Peter J. Attar ◽  
Raymond E. Gordnier ◽  
Jordan W. Johnston ◽  
William A. Romberg ◽  
Ramkumar N. Parthasarathy
Keyword(s):  
Strouhal Number ◽  
Limit Cycle ◽  
Lift Coefficient ◽  
Angle Of Attack ◽  
Micro Air Vehicles ◽  
Element Model ◽  
Wing Membrane ◽  
Reduced Frequency ◽  
Membrane Wing ◽  
Air Vehicles

The fluid and structural response of two different membrane wing Micro Air Vehicles is studied through computation and experiment. A (three) batten-reinforced fixed wing membrane micro air vehicle is used to determine the effect of membrane prestrain and fixed angle of attack on flutter and limit cycle behavior of fixed wing membrane Micro Air Vehicles. For each configuration tested, flutter and subsequent limit cycle oscillations are measured in wind tunnel tests and predicted using an aeroelastic computational model consisting of a nonlinear finite element model coupled to a vortex lattice solution of the Laplace equation and boundary conditions. Correlation between the predicted and measured onset of limit cycle oscillation is good as is the prediction of the amplitude of the limit cycle at the trailing edge of the lower membrane. A direct correlation between levels of strain and the phase of the membranes during the limit cycle is found in the computation and thought to also occur in the experiment. The second membrane wing micro air vehicle configuration is that of a plunging membrane airfoil model. This model is studied computationally using a sixth-order finite difference solution of the Navier-Stokes equations coupled to a nonlinear string finite element model. The effect, on the structural and fluid response, of plunging Strouhal number, reduced frequency and static angle of attack is examined. At two degree angle of attack, and Strouhal number of 0.2, the effect of increasing the plunging reduced frequency is to decrease the sectional lift coefficient and increase the sectional drag coefficient. At this angle of attack, minimal change in the sectional lift coefficient is found when increasing from a Strouhal number of 0.2 to 0.5 at reduced frequencies of 0.5 and 5.903, the lowest and highest values of this parameter which are studied in this work. For this angle of attack the maximum change which occurs when increasing the Strouhal number from 0.2 to 0.5 is at a reduced frequency of 1.5. When the effect of angle of attack is studied, it is found that at a Strouhal number of 0.5 and reduced frequency of 1.5 the plunging flexible model demonstrates improved lift characteristics over the fixed flexible airfoil case. The greatest improvement occurs at an angle of attack of 2 degrees followed by 10 degrees and then 6 degrees. Finally the effect on the flow characteristics of airfoil flexibility is investigated by increasing the membrane pre-strain from a nominal value of 5 percent to that of 20 percent. This increase in pre-strain results in a reduced value of sectional lift coefficient as compared the 5 percent pre-strain case at the same fixed angle of attack, Strouhal number and reduced frequency.

scholarly journals Simulating unmanned aerial vehicle swarms with the UB-ANC Emulator

2019 ◽  
Vol 11 ◽  
pp. 175682931983766 ◽  
Author(s):  
Jalil Modares ◽  
Nicholas Mastronarde ◽  
Karthik Dantu
Keyword(s):  
Discrete Event ◽  
Micro Air Vehicles ◽  
Wireless Channel ◽  
Micro Air Vehicle ◽  
Mobility Control ◽  
Network Simulator ◽  
Packet Losses ◽  
Coverage Path Planning ◽  
Air Vehicle ◽  
Air Vehicles

Recent advances in multi-rotor vehicle control and miniaturization of hardware, sensing, and battery technologies have enabled cheap, practical design of micro air vehicles for civilian and hobby applications. In parallel, several applications are being envisioned that bring together a swarm of multiple networked micro air vehicles to accomplish large tasks in coordination. However, it is still very challenging to deploy multiple micro air vehicles concurrently. To address this challenge, we have developed an open software/hardware platform called the University at Buffalo’s Airborne Networking and Communications Testbed (UB-ANC), and an associated emulation framework called the UB-ANC Emulator. In this paper, we present the UB-ANC Emulator, which combines multi-micro air vehicle planning and control with high-fidelity network simulation, enables practitioners to design micro air vehicle swarm applications in software and provides seamless transition to deployment on actual hardware. We demonstrate the UB-ANC Emulator’s accuracy against experimental data collected in two mission scenarios: a simple mission with three networked micro air vehicles and a sophisticated coverage path planning mission with a single micro air vehicle. To accurately reflect the performance of a micro air vehicle swarm where communication links are subject to interference and packet losses, and protocols at the data link, network, and transport layers affect network throughput, latency, and reliability, we integrate the open-source discrete-event network simulator ns-3 into the UB-ANC Emulator. We demonstrate through node-to-node and end-to-end measurements how the UB-ANC Emulator can be used to simulate multiple networked micro air vehicles with accurate modeling of mobility, control, wireless channel characteristics, and network protocols defined in ns-3.

scholarly journals A design methodology for quiet and long endurance MAV rotors

2019 ◽  
Vol 11 ◽  
pp. 175682931984593 ◽  
Author(s):  
Ronan Serré ◽  
Hugo Fournier ◽  
Jean-Marc Moschetta
Keyword(s):  
Design Method ◽  
Micro Air Vehicles ◽  
Fast Response ◽  
Micro Air Vehicle ◽  
Broadband Noise ◽  
Design Parameters ◽  
Acoustic Signature ◽  
Air Vehicle ◽  
Long Endurance ◽  
Air Vehicles

Over the last 10 years, the use of micro air vehicles has rapidly covered a broad range of civilian and military applications. While most missions require optimizing the endurance, a growing number of applications also require acoustic covertness. For rotorcraft micro air vehicles, combining endurance and covertness heavily relies on the capability to design new propulsion systems. The present paper aims at describing a complete methodology for designing quiet and efficient micro air vehicle rotors, ranging from preliminary aerodynamic prediction to aeroacoustic optimization to experimental validation. The present approach is suitable for engineering purposes and can be applied to any multirotor micro air vehicle. A fast-response and reliable aerodynamic design method based on the blade-element momentum theory has been used and coupled with an extended acoustic model based on the Ffowcs Williams and Hawkings equation as well as analytical formulations for broadband noise. The aerodynamic and acoustic solvers have been coupled within an optimization tool. Key design parameters include the number of blades, twist and chord distribution along the blade, as well as the choice of an optimal airfoil. An experimental test bench suitable for non-anechoic environment has been developed in order to assess the benefit of the new rotor designs. Optimal rotors can maintain high aerodynamic efficiency and low acoustic signature with noise reductions in the order of 10 dB(A).

Generic Theoretical and Experimental Development of Micro Aerial Vehicle Using Fundamental Principles

2014 ◽  
Vol 564 ◽  
pp. 110-117
Author(s):  
Harijono Djojodihardjo ◽  
Muljo Widodo Kartidjo
Keyword(s):  
Leading Edge ◽  
Micro Air Vehicles ◽  
Flapping Wing ◽  
Theoretical Development ◽  
Phase Lag ◽  
Test Bed ◽  
Experimental Development ◽  
New Variant ◽  
Air Vehicle ◽  
Air Vehicles

Flapping Wing Micro Air Vehicles (FWMAV) and Quad-Rotor Micro Air Vehicles (QRMAV) are strategic for many applications, applications, ranging from control device test bed to perform difficult tasks as well as to perform surveillance mission to unreachable places. While salient features and functional significance of the various components in the flying bio-systems can be synthesized into a simplified and generic and simplified model of a flapping Bi-Wing and Quad-Wing Ornithopter; Quad-Rotor Micro Air Vehicle could be utilized for developing emerging Personal Air Vehicle (PAV) technologies. Theoretical development of Bio-Inspired Bi-Wing and Quad-Wing Flapping Wing Micro Air Vehicles is outlined by considering the motion of a three-dimensional rigid and thin wing in flapping and pitching motion with phase lag. Basic Unsteady Aerodynamic Approach incorporating viscous effect and leading-edge suction is utilized. Theoretical and experimental development of a new variant of Quad-Rotor Micro Air Vehicles is also outlined. The theoretical development of these potential MAVs is carried out using a first principle approach starting from the Euler-Newton equations of motion.

Teaching micro air vehicles how to fly as we teach babies how to walk

2013 ◽  
Vol 24 (8) ◽  
pp. 936-944 ◽  
Author(s):  
Jae-Hung Han ◽  
Dong-Kyu Lee ◽  
Jun-Seong Lee ◽  
Sang-Joon Chung
Keyword(s):  
Magnetic Levitation ◽  
Micro Air Vehicles ◽  
Micro Air Vehicle ◽  
Constraint Forces ◽  
Minimum Requirement ◽  
Alternative Approach ◽  
Air Vehicle ◽  
Constant Altitude ◽  
The Stability ◽  
Air Vehicles

Recently, various micro air vehicles have drawn significant attention in numerous areas including surveillance and reconnaissance. The manual control of micro air vehicles is very difficult due to their smaller profile; therefore, a stability and controllability augmentation system is a minimum requirement for stable and efficient flight. However, it is not easy to obtain an accurate numerical model for the flight dynamics of micro air vehicles in the design of the stability and controllability augmentation system. An alternative approach for the stability and controllability augmentation systems is to incorporate reinforcement learning in order to address the numerical complexity. However, in order to train micro air vehicles to learn how to fly, they must first be airborne. This article presents a new method that provides an effective environment where a micro air vehicle can learn to fly in a similar manner to an infant learning to walk. The test setup was constructed to enable the magnetic levitation of a micro air vehicle that has a permanently embedded magnet. This apparatus allows for flexible experimentation: the position and attitude of the micro air vehicle, the constraint forces, and the resulting moments are adjustable and fixable. This “ Pseudo Flight Environment” was demonstrated using a fixed-wing micro air vehicle model. Furthermore, in order for the model to maintain a constant altitude, a height hold control system was devised and implemented.

scholarly journals Batch Manufacturing of Split-Actuator Micro Air Vehicle Based on Monolithic Processing Technology

Micromachines ◽  
2021 ◽  
Vol 12 (10) ◽  
pp. 1270
Author(s):  
Xiang Lu ◽  
Chengxiang Wang ◽  
Kun Lu ◽  
Xiang Xi ◽  
Yulie Wu ◽  
...  
Keyword(s):  
Laser Cutting ◽  
Micro Air Vehicles ◽  
Flapping Wing ◽  
Processing Technology ◽  
Composite Sheet ◽  
Manufacturing Method ◽  
Wide Range ◽  
Air Vehicle ◽  
Design And Manufacture ◽  
Air Vehicles

Microrobots have a wide range of applications. The rigid–flexible composite stereoscopic technology based on ultraviolet laser cutting technology is primarily researched for the design and manufacture of microrobots and has been used to fabricate microscale motion mechanisms and robots. This paper introduces a monolithic processing technology based on the rigid–flexible composite stereoscopic process. Based on this process, a split-actuator micro flapping-wing air vehicle with a size of 15 mm × 2.5 mm × 30 mm was designed. We proposed a batch manufacturing method capable of processing multiple micro air vehicles at the same time. The main structure of 22 flapping-wing micro air vehicles can be processed at the same time within the processing range of the composite sheet with an area of 80 mm × 80 mm, and the processing effect is good.

Dynamic Stability of Flapping-Wing Micro Air Vehicles With Unsteady Aerodynamic Model

2017 ◽  
Author(s):  
Jae-Hung Han ◽  
Anh Tuan Nguyen
Keyword(s):  
Dynamic Stability ◽  
Ground Effect ◽  
Micro Air Vehicles ◽  
Numerical Approach ◽  
Linearization Method ◽  
Flapping Wing ◽  
Free Flight ◽  
Unsteady Aerodynamic ◽  
Aerodynamic Model ◽  
Air Vehicles

In this paper, we introduce a numerical approach based on an unsteady aerodynamic model to study the dynamic stability of insect-like flapping-wing micro air vehicles (FWMAVs). Trimmed free flight of FWMAVs is simulated by a framework that couples the unsteady potential-based aerodynamic model and a multibody dynamics code. Flight dynamic modal structures are obtained by a linearization method. This paper also briefly presents the applications of the abovementioned approach to study several problems associated with the flight dynamic stability of FWMAVs, such as the effects of body aerodynamics and wing flexibility, as well as the ground effect.

The effects of rectangular riblets on rectangular micro air vehicles for drag reduction

2016 ◽  
Vol 231 (2) ◽  
pp. 364-373 ◽  
Author(s):  
Mohammadreza Radmanesh ◽  
Iman Samani ◽  
Alireza Amiriyoon ◽  
Mohammad-Reza Tavakoli
Keyword(s):  
Drag Reduction ◽  
Drag Coefficient ◽  
Angle Of Attack ◽  
Micro Air Vehicles ◽  
Turbulent Model ◽  
Air Vehicle ◽  
Almost All ◽  
Drag Ratio ◽  
Lift To Drag Ratio ◽  
Air Vehicles

Reduced drag, increased lift and, consequently, increased vital ratio and lift-to-drag coefficients are crucial in almost all efficient micro air vehicles. Riblet geometries use a variety of air vehicles. Further investigation on micro air vehicles is, however, necessary for enhanced development. Rectangular riblets on a rectangular micro air vehicle are computationally investigated. In this study, the governing equation of fluid flow is solved numerically; the turbulent model around the NACA S5020 airfoil section is covered by riblets either on both sides or on the upper side of the wings. Results show a difference of behavior in drag reduction due to the angle of attack on the airfoil. When the lift-to-drag coefficient of an angle of attack is at its maximum, an improvement can be observed, where lift-to-drag ratio increases, and drag decreases. Results for the two-side riblets show an increase in the lift-to-drag ratio as well; although the lift-to-drag coefficient and the drag reduction of riblets on both sides were comparatively less than that for riblets on the upside.

Sign in / Sign up

Export Citation Format

Share Document