Comparative Study of Two and Three Blade Mini Propellers Aerodynamic Performance

An optimized and comprehensive method is used to design and manufacture a fixed wing micro air vehicle (MAV) with Zimmerman planform. The design process includes four stages which are the specification of the flight mission, determination of the best aspect ratio, identification of the optimum wing loading and thrust loading values, and estimation of the weight of the structural components of the MAV. To do this, various statistical and analytical methods are utilized. Based on an aerodynamic analysis, the results show that an optimum aspect ratio that maximizes the performance of the Zimmerman MAV for a well-defined cruise speed is determined. Considering six possible flights, a constraint analysis is performed and an optimum wing loading value is determined. It is shown that the computational method is beneficial to determine the exact masses for the structural components including the wing, fuselage, and vertical tail. Using the 3D panel method, the determination of the shape of the reflexed airfoil for the MAV is successfully done by minimizing the drag force and the angle of attack to use less powerful motor and avoid any stall effect, respectively. A stability analysis is then performed to check the safe flight of the designed vehicle. During test flight, the results show that the designed Zimmerman MAV satisfies the pre-defined specification. The final characteristics of the manufactured MAV are: wingspan of 44 cm, weight of 450 g, aspect ratio of 1.51, cruise speed of 20 m/s, and flight endurance of 20 min.

A comprehensive method is used to design and manufacture a fixed wing micro air vehicle (MAV) with Zimmerman planform. The design process includes four stages which are the specification of the flight mission, determination of the best aspect ratio, identification of the optimum wing loading, and estimation of the weight of the structural components of the MAV. To this end, various statistical and analytical methods are utilized. Based on an aerodynamic analysis, the results show that an optimum aspect ratio that maximizes the performance of the Zimmerman MAV for a well-defined cruise speed is determined. Considering six possible flights, a constraint analysis is performed and an optimum wing loading value is found. Using the 3D panel method, the determination of the shape of the reflexed airfoil for the MAV is successfully done by minimizing the drag force and the angle of attack to use less powerful motor and avoid any stall effect, respectively. During test flight, the results show that the designed Zimmerman MAV satisfies the predefined specification. The final characteristics of the manufactured MAV are: wingspan of 44 centimeters, weight of 450 grams, aspect ratio of 1.51, cruise speed of 20m/s, and flight endurance of 20 minutes.

A solution to the waypoint navigation problem for the fixed wing micro air vehicles (MAV) having a severe coupling between longitudinal and lateral dynamics, in the framework of integrated guidance and control (IGC) is addressed in this paper. IGC yields a single step solution to the waypoint navigation problem, unlike conventional multiple loop design. The pure proportional navigation (PPN) guidance law is integrated with the coupled MAV dynamics. A multivariable static output feedback (SOF) controller is designed for the linear state space model formulated in IGC framework. A waypoint navigation algorithm is proposed that handles the minimum turn radius constraint of the MAV and also evaluates the feasibility of reaching a waypoint. Non-linear simulations with and without wind disturbances are performed on a high fidelity 150 mm wingspan MAV model to demonstrate the proposed waypoint navigation algorithm.

Simulation and Analysis of Integral LQR Controller for Inner Control Loop Design of a Fixed Wing Micro Aerial Vehicle (MAV)

MAVs (micro air vehicles) with a maximal dimension of 15 cm and nominal flight speeds of around 10 m s−1, operate in a Reynolds number regime of 105 or lower, in which most natural flyers including insects, bats and birds fly. Furthermore, due to their light weight and low flight speed, the MAVs' flight characteristics are substantially affected by environmental factors such as wind gust. Like natural flyers, the wing structures of MAVs are often flexible and tend to deform during flight. Consequently, the aero/fluid and structural dynamics of these flyers are closely linked to each other, making the entire flight vehicle difficult to analyze. We have recently developed a hummingbird-inspired, flapping flexible wing MAV with a weight of 2.4–3.0 g and a wingspan of 10–12 cm. In this study, we carry out an integrated study of the flexible wing aerodynamics of this flapping MAV by combining an in-house computational fluid dynamic (CFD) method and wind tunnel experiments. A CFD model that has a realistic wing planform and can mimic realistic flexible wing kinematics is established, which provides a quantitative prediction of unsteady aerodynamics of the four-winged MAV in terms of vortex and wake structures and their relationship with aerodynamic force generation. Wind tunnel experiments further confirm the effectiveness of the clap and fling mechanism employed in this bio-inspired MAV as well as the importance of the wing flexibility in designing small flapping-wing MAVs.

This thesis studies a controllability approach for general resonant compliant systems. These systems exploit resonance to obtain a specific dynamic response at relatively low actuation power. This type of systems is often lightweight, is scalable and minimizes frictional losses through the use of compliant hinges. Some insect-inspired Flapping Wing Micro Air Vehicle (FWMAV) designs are based on such a resonant compliant system. These designs are carefully tuned such that a particular resonance response of the system corresponds to the desired wing flapping motion. The system’s resonance response depends strongly on its structural properties (i.e., mass, damping, stiffness and their spatial distribution). Resonance response modifications can, thus, be controlled using carefully selected structural property changes. This thesis contributes to the controllability of resonant compliant systems in general and the compliant FWMAV design in particular. Although there is yet no physical, controllable FWMAV design with integrated active components, the current research strongly indicates the applicability of structural property changes to reach controllability of this type of systems. Effective control requires an integrated approach that considers simultaneously the structure, the wings, the kinematics, the methods to induce property changes and the desired controllability.

Insect-sized flapping wing micro air vehicles (MAVs) are beginning to take flight but have many technical hurdles to overcome. One of the greatest challenges of MAV design is attaining lightweight microelectronic components of optimal size and shape. In this paper an inductor for incorporation onto a carbon fiber MAV body component is modeled using a multiphysics and lumped parameter approach. A magnetostatic simulation using finite elements provides insight into the magnetic flux density distribution of the inductor. Simulation allows the inductor to be adapted to various shapes and sizes. Lumped values are generated based upon desired values for a MAV inductor. Microelectromechanical systems (MEMS) processes are used to fabricate the inductor directly on a MAV carbon fiber body (e.g. fuselage) component. Fabrication is prototyped on a semiconductor wafer. The inductor (a major contributor to the MAV weight budget) forms the basis for a lightweight, voltage transformer. By transferring the copper conductors to a structural component, the circuitry becomes part of the vehicle structure. This type of MEMS fabrication allows for optimal sizing, weight reduction, a lower part count and much higher levels of integration. These parameters are critical for operational MAV applications.

Fixed-wing MAV attitude stability in atmospheric turbulence—Part 2: Investigating biologically-inspired sensors

In this study the aerodynamic efficiency of DelFly, a bio-inspired napping wing Micro Air Vehicle (MAV), is analyzed. DelFly has four flexible sail-like wings placed in a biplane configuration and is believed to produce favorable lift in comparison to conventional wings. This is at the expense of higher drag and thus loss off efficiency. This study uses experimental setups to investigate the power required to drive the flapping wings as a function of the kinematic parameters flap frequency and flap angle. This is done during hovering flight, the most power consuming mode. In addition, the deformation of the Mylar-film wings is filmed in free air conditions and in near-vacuum conditions to identify the aerodynamic versus inertial effects. The experimental results of the studies present valuable insight in the aerodynamic performance and structural dynamics of the vehicle. For hovering with a flap frequency of 14 Hz, an optimal flap angle has been found that maximizes thrust for minimal power consumption. High lift coefficient values suggest that the favorable lift production in comparison to conventional wings, is a result of high lift mechanisms. These are believed to be the Leading Edge Vortex and the clap-and-fling motion.

Micro Air Vehicles (MAVs) have become more attractive for various missions including surveillance or reconnaissance in recent years. MAVs should be capable of maintaining their attitudes through either inherent passive stability or active feedback in order to successfully perform their directives. Stability and Controllability Augmentation Systems (SCASs) are usually employed to enhance the flight performance of conventional aircrafts and Unmanned Aerial Vehicles (UAVs). However, it is no simple task to obtain an accurate numerical model for the flight dynamics of a MAV. An alternative approach for SCASs would be to incorporate reinforcement learning in order to address this numerical complexity. Such implementation has already been successful in other vehicles, such as unmanned ground vehicles (UGVs), because of their bettered stability compared to aerial vehicles. However, in order to train MAVs to learn how to fly, they must first be airborne. Similar to teaching infants how to walk, this paper presents a new method to provide an effective environment where a MAV can learn how to fly. A test setup was constructed to enable magnetic levitation of a MAV embedded with a permanent magnet. This apparatus allows for flexible experimentation: the position and the altitude of the MAV, the constraint forces, and the resulting moments are all adjustable and fixable. This ‘Pseudo Flight Environment’ was demonstrated with a fixed wing MAV model. In order for the model to maintain a constant altitude, a height hold control system was devised and implemented.

An implementation of nonlinear dynamics of a flapping wing micro air vehicle (MAV) based on new aerodynamic expressions is presented. These new expressions for cycleaveraged force coefficients are quadratic polynomial functions of the local Reynolds number, Strouhal number, geometric function and the stroke angle of attack. The functions are based on the sensitivity analysis study done on the force generation by wing flapping mechanism. The MAV model consists of a main body and two wings. The nonlinear dynamics is simulated with the flapping frequency as the control input. The aerodynamic forces generated using this method are compared with that obtained using earlier implementation of the MAV dynamics based on different set of aerodynamic expressions. The results show that the force generation using flapping mechanism can be regularized by using the cycle-averaged force coefficients.

Missions envisioned for Micro Air Vehicles (MAVs) such as Intelligence, Surveillance and Reconnaissance (ISR) in urban environments require exceptional agility. These missions typically involve ight through or in close proximity to buildings, tunnels and trees, and require the MAVs to maneuver using sharp dives and climbs along with small-radius turns. The small size of MAVs allows such ight operations within con ned space but the control e ectors must provide su cient maneuverability, while maintaining stability, with only limited sensing capability onboard the platform. To meet these challenges, researchers have long been attracted by the amazing attributes of biological systems, such as those exhibited by birds and insects. Birds can y in dense ocks, executing rapid maneuvers with g-loads far in excess of modern ghter aircrafts, and yet never collide with each other, despite the absence of air tra c controllers. This paper introduces a novel framework for the design and control of a Micro Air Vehicle. The vehicle's conceptual design is based on biologically-inspired principles and emulates a dragon y (Odonata-Anisoptera). The author is borrowing ight mechanism features from the dragon y and merging them with indigenous designs in creating a novel version of a Flapping Wing MAV, called the QV. The QV design incorporates the simplicity of mechanical construction and the complexity of a sophisticated multi-layered Hybrid & Linear / Non-Linear controller to achieve extended ight times and improved agility compared to other Rotary and Flapping Wing MAV designs. The paper talks about the design and control features of the proposed QV design and gives an overview on the developmental e orts been made towards the prototyping of the QV yer. The potential applications for such a high endurance vehicle are numerous, including air-deployable mass surveillance in cluster and swarm formations. The disposability of the vehicle would help in battleeld deployment as well, where such a MAV would be made available to soldiers for proximity sensing and threat level assessment. Other applications would include search and rescue operations and civilian law-enforcement.

Numerical study of flapping wing/tail aerodynamic interaction for flapping wing micro air vehicle

PAC: A novel self-adaptive neuro-fuzzy controller for micro aerial vehicles

We designed a X-type wing of flapping-wing Micro Air Vehicles (MAV) and doing some aerodynamic force testing by the flapping-wing MAV aerodynamic force testing device which designed by ourselves. In order to study the relationship of aerodynamic force on the flapping-wing models, we do these tests of different flapping-wing models in different angles of attack and flapping frequency. Found that X-wings flapping wing MAV rely mainly on aerodynamic wings folded back when the compressed gas emitted and received; increase the X-wings flapping wing MAV flapping frequency can significantly increase aerodynamic wings; and X-flapping wing MAV Aerodynamic wing root shoot ratio and aspect ratio with the decrease, inversely proportional to the relationship.