E. Rizzo

The PrandtlPlane Configuration: Overview on Possible Applications to Civil Aviation

The term PrandtlPlane indicates an aircraft configuration based on a box-like lifting system in the front view. The PrandtlPlane configuration allows one to conceive many different aircrafts for both passenger and freighter aviation, ranging from small Unmanned Aerial Vehicles (UAVs) to very large civil aircrafts, much larger than the present largest ones; different engine and propulsion systems became possible in view of the so-called “green aviation” of the future.

A model for solar powered aircraft preliminary design

Solar powered aircraft are becoming more and more interesting for future long endurance missions at high altitudes, because they could provide Earth monitoring, telecommunications, etc. without any atmospheric pollution and, hopefully in the near future, with competitive costs compared with satellites. The research activities carried out till now have been mainly focused on flying wings or conventional aircraft configurations, with a great emphasis on the technological aspects. The present paper aims to define a mathematical model for solar powered aircraft preliminary design, valid independently of the aerodynamic configuration. A preliminary analysis is carried out in order to simulate Helios and the results are compared with those available from the flights of this aircraft. The proposed mathematical model is used also to compare four different aircraft configurations, namely: a flying wing, a conventional aircraft, a twin boom aircraft and a biplane aircraft. The results obtained are discussed in the paper and an optimum aircraft is analysed.

Application of Optimisation Algorithms to Aircraft Aerodynamics

Reduced operating costs and low environmental impact are required to modern commercial aircraft. The today airplanes are so optimized that a significant increase in performances can hardly be achieved and new configurations are now of interest, supposing to allow a jump forward in drag reduction. In the present work, optimization algorithms are applied to search new aircraft configurations able to satisfy different constraints. The algorithms are first applied to benchmarking problems in order to test their performances and evaluate the computational time. The same algorithms are applied to classical problems of aerodynamics like the optimum wings. At the end, the problem of trim and stability of flight are tackled; we look for wing planforms which satisfy a set of constraints defining the feasible region both in cruise condition and in low speed condition (i.e. when high lift devices are deployed). Finally, a new ultralight optimised aircraft is presented as an example of application.

Variational Approach to the Problem of the Minimum Induced Drag of Wings

A closed form solution of the problem of the minimum induced drag of a finite span straight wing was given by Prandtl. In this chapter, a mathematical theory, based on a variational approach, is proposed in order to revise such a problem and provide one with a support for optimizing more complex wing configurations, which are becoming of interest for future aircraft. The first step of the theory consists in finding a class of functions (lift distributions) for which the induced drag functional is well defined. Then, in this class, the functional to be minimized is proved to be strictly convex; taking into account this result, it is proved that the global minimum solution exists and is unique. Subsequently, we introduce the image space analysis associated with a constrained extremum problem; this allows us to define the Lagrangian dual of the problem of the minimum induced drag and show how such a dual problem can supply a new approach to the design. After having obtained the Prandtl exact solution in the context of a variational formulation, a numerical algorithm, based on the Ritz method, is presented, and its convergence is proved.

Design of an airfreight system based on an innovative PrandtlPlane aircraft

The PrandtlPlane configuration is conveniently applied to very large aircraft and, in this paper, the design of a freighter of 24 intermodal containers is chosen as a significant example of application. The maximum range of this big freighter is 3.000 miles. The range limitation is accomplished by the definition of a set of freight airports to be positioned properly worldwide; a mathematical theory has been formulated in order to optimize the positions of these dedicated airports on the basis of economical parameters; some examples are shown in the first part.. The second part of the paper is dedicated to the optimization of the aircraft configuration, using a homemade optimization code; the objective function is the aerodynamic efficiency with constraints regarding the stability of flight and stall characteristics. A set of different local minima are determined, corresponding to solutions that satisfy all the constraints imposed and the absolute minimum is chosen inside this set on the basis of further conditions on structural aspects. The solutions include PrandtlPlanes in which a third lifting surface is considered in addition to the configuration.

Bioinspired Mechanisms and Sensorimotor Schemes for Flying: A Preliminary Study for a Robotic Bat

The authors present a critical review on flying motion and echolocation in robotics, directly derived from research on biology and flight mechanics of bats, aimed at designing and prototyping a new generation of robotic technologies.

A personal robotic flying machine with vertical takeoff controlled by the human body movements

We propose a cooperative research project aimed at designing and prototyping a new generation of personal flying robotic platform controlled by movements of the human body using a symbiotic human-robot-flight machine interaction. Motors with ducted fun propulsion and power supply, and a VSLAM system will be integrated in the final flight machine with short and vertical takeoff and landing capability and composite (or light alloy) airframe structure for low speed and low altitude flight. In the project, we will also develop a flight simulator to test the interaction between the flying machine and the human body movements. In this first step, for human safety, the flying machine will be controlled by an autopilot colligated in a closed-loop control with the simulator.