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The aim of this work is to apply an innovative adaptive ℒ1 techniques to control flutter phenomena affecting highly flexible wings and to evaluate the efficiency of this control algorithm and architecture by performing the following tasks: i) adaptation and analysis of an existing simplified nonlinear plunging/pitching 2D aeroelastic model accounting for structural nonlinearities and a quasi-steady aerodynamics capable of describing flutter and post-flutter limit cycle oscillations, ii) implement the ℒ1 adaptive control on the developed aeroelastic system to perform initial control testing and evaluate the sensitivity to system parameters, and iii) perform model validation and calibration by comparing the performance of the proposed control strategy with an adaptive back-stepping algorithm. The effectiveness and robustness of the ℒ1 adaptive control in flutter and post-flutter suppression is demonstrated.

This paper discusses the various factors that were addressed in the planning process for the design and construction of an unmanned aerial vehicle (UAV) destined for use as a multirole research aircraft for Clarkson University. Details related to mission requirements, cost, construction materials, manufacturing methods, and regulatory requirements will be discussed. The resulting airframe, structure, manufacturing, and control system plan of action will be laid out. An overview of anticipated FAA regulations will be presented, and the need to design for conformity to said regulations addressed. Emphasis will be placed on design and manufacturing decisions relating to the extensive use of composite materials throughout the aircraft.

Scaled models are often used to check the aerodynamic performance of full scale aircraft and airship concepts, which have gone through a conceptual and preliminary design process. Results from these tests can be quite useful to improve the design of unconventional airships whose aerodynamics might be quite different from classical configurations. Once the airship geometry has been defined, testing is required to acquire aerodynamic data necessary to implement the mathematical model of the airship needed by the flight control system to develop full autonomous capabilities. Rapid prototyping has the great potential of playing a beneficial role in unconventional autonomous airship design similarly to the success obtained in the design process of conventional aircrafts.

Newly developed technologies are enabling the design of Unmanned Aerial Vehicles (UAVs) and Micro Air Vehicles (MAVs) with heretofore unrealized capabilities. A tube-launch MAV would allow the increased flexibility to launch an aircraft rapidly without need for a runway or complex launching system, either from a vehicle, installation, or as a man-portable device. The MAV would fill the diameter of the launch tube and deploy aerodynamic lifting and control surfaces after launch. In order to deploy the lifting surfaces the MAV must be capable of deploying control surfaces, negating any tube-imparted roll rate, and developing an optimal flight attitude automatically. An experimental method was developed to characterize the aerodynamics and stability of a blunt body spinning under conditions of roll rate decay in the Clarkson University High Speed Wind tunnel. This method is to be used to evaluate the development of an active roll rate control system for spinning projectiles.

Flow control over aerodynamic shapes in order to achieve performance enhancements has been a lively research area for last two decades. Synthetic Jet Actuators (SJAs) are devices able to interact actively with the flow around their hosting structure by providing ejection and suction of fluid from the enclosed cavity containing a piezo-electric oscillating membrane through dedicated orifices. The research presented in this paper concerns the implementation of zero-net-mass-flux SJAs airflow control system on a NACA0015, low aspect ratio wing section prototype. Two arrays with each 10 custom-made SJAs, installed at 10% and 65% of the chord length, make up the actuation system. The sensing system consists of eleven acoustic pressure transducers distributed in the wing upper surface and on the flap, an accelerometer placed in proximity of the wing c.g. and a six-axis force balance for integral load measurement.

In this paper two different tools have been applied to the problem of designing a small UAV. With these tools a parametric study of wing configuration and sizing was performed. The focus of this study was to optimize range and endurance of the UAV during a particular flight mission. The two numerical analysis tools applied to the UAV wing design were developed for widely different analysis problems. The first tool, the aircraft DATCOM was developed for the preliminary design analysis of manned aircraft and will be used to perform parametric modeling and geometry optimization. The Projectile Rocket Ordinance Design and Analysis System (PRODAS®) software was developed for ballistic projectiles and will be used for 6 DOF fixed plane trajectory simulation of the developed UAV concepts. While the scale of the UAV selected does not match well with the DATCOM software, the mission requirements and analysis format of the software is advantageous.

This paper describes the design and development of a virtual environment conceived to support flight operations of an Unmanned Air Vehicle (UAV) used for wind mapping in the proximity of existing or planned wind farms. The virtual environment can be used in pre-flight briefings aiming to define a trajectory from a list of waypoints, to change and eventually re-plan the mission in case of intersection with no fly zones, to simulate the mission, and to preview images/videos taken from the UAV on-board cameras. During flight, the tool can be used to compute the wind speed along the trajectory by analyzing the data streaming from the UAV. The integration of Augmented Reality (AR) techniques in the flight environment provides assistance in remotely piloted landings, and allows visualizing flight and environmental information that are critical to the mission.

Active flow control devices such as zero-net-mass-flux actuators have broad aeronautical applications. Among them, low power and lightweight Synthetic Jet Actuators can be used to improve the performance of flight vehicles, providing load alleviation capabilities, expanding their flight envelope, and preventing catastrophic failure by aeroelastic instabilities. Numerical and experimental investigations are proving that SJAs are effective in actively altering the boundary layer; the effect of the momentum exchange due to the SJAs leads to a rearrangement of streamlines, a virtual aerodynamic shaping that enable changes in the aerodynamics forces acting on the lifting surfaces. This paper discusses development aspects that the authors have been conducting on the topic with applications to load alleviation and flutter suppression for aircraft wings.

Added masses computation is a crucial aspect to be considered when the density of a body moving in a fluid is comparable to the density of the fluid displaced: added mass can be defined as the inertia added to a system because an accelerating or decelerating body displaces some volume of neighboring fluid as it moves through it. The motion of vehicles like airships and ships can be addressed only by keeping into account the effect of added masses, while in case of aircrafts and helicopters this contribution is usually neglected. Lighter Than Air flight simulation, unmanned airships flight control system, airships flight dynamics are typical applications in which added masses are fundamental to achieve an effective and realistic modeling. A panel based method using the mesh of an airship external shape is developed to account for the added massed.