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1 – 10 of 10Said Chaabani and Naoufel Azouz
This paper presents preliminary results of the modeling of a large autonomous quad-rotor airship, with flying wing shape. This airship is supposed to be a flexible body. This…
Abstract
Purpose
This paper presents preliminary results of the modeling of a large autonomous quad-rotor airship, with flying wing shape. This airship is supposed to be a flexible body. This study promotes an entirely analytical methodology with some assumptions. In this study and as first assumption, the shape of the careen is supposed to be an elliptic cone. To retrieve the velocity potential shapes, this paper solved the Laplace’s equation by using the sphero-conal coordinates. This leads to the Lamé’s equations. The whole system equations governing the interaction of air–structure, including the boundary conditions, is solved in an analytical setting.
Design/methodology/approach
This paper opted for a modeling and determination of the added masses of a flexible airship by an analytical method illustrated by a comparison with a geometric method. This analytical method includes the study of complex functions which are the Lamé functions.
Findings
This paper provides an analytical way to estimate an aerodynamic phenomenon which acts on the airship and in particular on its envelope and known as the phenomenon of added masses or virtual masses, as well as the means of defining it and the calculation analytically for the case of the flexible airship.
Research limitations/implications
Considering that the calculation of the added masses is very difficult and the numerical methods increase the number of degrees of freedom, the analytical method established in this paper has become a solution of calculations of these virtual masses.
Practical implications
This paper includes an application for determining the added masses of a new generation MC500 airship.
Originality/value
This paper allows defining an analytical method which determines the added masses of an airship, which helps the automation engineer to develop a control strategy to stabilize this airship.
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Alessandro Ceruti and Pier Marzocca
This paper aims to describe a methodology to optimize the trajectory of unconventional airship performing a high-altitude docking manoeuvre.
Abstract
Purpose
This paper aims to describe a methodology to optimize the trajectory of unconventional airship performing a high-altitude docking manoeuvre.
Design/methodology/approach
The trajectories are based upon Bezier curves whose control points positions are optimized through particle swarm optimization algorithm. A minimum energy strategy is implemented by considering the airship physical properties. The paper describes the mathematical model of the airships, the trajectories modelling through Bezier’s curves and the optimization framework. A series of test cases has been developed to evaluate the proposed methodology.
Findings
Results obtained show that the implemented procedure is able to optimize the airship trajectories and to support their in-flight docking; a strong influence of the wind speed and course on the trajectories planning is highlighted.
Research limitations/implications
The wind speed considered in these simulations depends only on altitude, and gusts effect has been neglected.
Practical implications
The proposed model can support the study of unconventional airship trajectories and can be useful to evaluate best in-air docking strategies.
Originality/value
The paper addresses the problem of trajectory optimization for a class of new air vehicles with an heuristic approach.
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Peter Tatham, Craig Neal and Yong Wu
Recent advances in aviation technology have seen the development of helium-filled “hybrid cargo airships” (HCAs) which have the potential to convey large payloads over significant…
Abstract
Purpose
Recent advances in aviation technology have seen the development of helium-filled “hybrid cargo airships” (HCAs) which have the potential to convey large payloads over significant distances at relatively low cost and with a small carbon footprint. The purpose of this paper is to demonstrate how such HCAs could be used to improve the logistic response to a rapid onset disaster.
Design/methodology/approach
Through consideration of three recent natural disasters (Typhoon Haiyan – The Philippines – 2013; The Nepal Earthquake – 2015; Cyclone Winston – Fiji – 2016), and drawing on both academic and practitioner literature, this paper provides an overview of how HCAs could potentially provide logistic support to those affected by similar disasters. The paper considers two scenarios: one in which the HCA replaces local truck or sea-based transport from an international airport to the disaster area, and the other in which it operates directly from a United Nations Humanitarian Response Depot to the disaster area.
Findings
The paper demonstrates that, when compared with the actual response to these three exemplar disasters, in the first scenario the use of HCAs provides a significantly faster but more expensive response; whereas in the second scenario, the timeline to supply is longer, but the costs are considerably less.
Research limitations/implications
This paper is conceptual in nature, but has been developed through an analysis of the literature related to both HCAs and humanitarian logistics. Given that the emerging generation of HCAs has yet to become fully operational, it will be important to continue to monitor their development and analyse the emerging speed/time/cost parameters in order to ascertain how HCAs might be optimally integrated into the logistic response to a disaster.
Practical implications
The significant cargo carrying capacity of an HCA together with its ability to operate from and into ad hoc locations (including those on water) would enable direct delivery from an international airhead or humanitarian response depot to an affected area. This has clear potential to enhance the efficiency, effectiveness and flexibility of post-disaster logistic operations.
Originality/value
Whilst there is some emerging discussion of the humanitarian-related use of HCAs in the literature, this generally reflects the technical aspects such as flight control systems and the actual operation of the airships. This paper is the first to offer a practical analysis of how HCAs might be used to support the work of the humanitarian logistician.
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IN recent years there has been a revival of interest in aerostatic aircraft. The natural advantages of “displacement type” flying machines have been often repeated but particular…
Abstract
IN recent years there has been a revival of interest in aerostatic aircraft. The natural advantages of “displacement type” flying machines have been often repeated but particular emphasis has been made on economy and safety. The prime reason is that power is required for propulstion and control and not for aerodynamic lift.
Jozsef Rohacs and Daniel Rohacs
The purpose of this paper is to present the first-year results of the EU-supported GABRIEL project on the possible use of magnetic levitation (MagLev) technology to assist…
Abstract
Purpose
The purpose of this paper is to present the first-year results of the EU-supported GABRIEL project on the possible use of magnetic levitation (MagLev) technology to assist aircraft take-off and landing (ATOL).
Design/methodology/approach
Developing a radically new technology is a complex task. It is based on extensive expert analysis, use of technology identification evaluation and selection methods, principle of the design philosophies and development of the radically new technologies.
Findings
A possible solution of using the MagLev technology to assist ATOL was developed and defined, including several original ideas, such as the cart-sledge concept or the unconventional climb principle.
Research limitations/implications
This is a typical “out-of-the-box” project without limitations on the developing new principles and technologies, but it is working on the development of a possible solution within the predictable technical and technological envelopes.
Practical implications
The developed concept should assess whether MagLev technology for the ATOL is feasible, cost-effective and safe.
Social implications
The developed GABRIEL principle may significantly reduce the noise and chemical emissions in airport regions and increase the efficiency of the air transportation system.
Originality/value
The GABRIEL concept is the first concept for using the MagLev technology to assist the takeoff and landing processes related to the commercial civil aviation.
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The future is often portrayed as rational, logical, and informed by the continuing achievements of the scientific and technological revolution. In similar ways, our own time was…
Abstract
The future is often portrayed as rational, logical, and informed by the continuing achievements of the scientific and technological revolution. In similar ways, our own time was seen as marked by such advances by futurists of earlier decades. But at the end of the twentieth century, resistance to the claims of mainstream science and technology has grown to an extent unanticipated in these earlier appraisals. This essay argues that such resistance is liable to flourish in the twenty‐first century, and that understanding why this should be the case is important for studies of the future. In particular, this essay takes up the Fortean approach. This approach examines areas of human experience that are “damned” by mainstream science, and also examines the processes and strategies adopted both by those effecting the damnation, and those challenging it. The case being made is that although we can expect many of these damned phenomena to remain excluded – deservedly so in some cases – this will not always be the case.
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THE Paris Aero Show is unique in that it is a regular exhibition, held every two years, thus permitting continuous comparisons of tendencies in design; its history being closely…
Abstract
THE Paris Aero Show is unique in that it is a regular exhibition, held every two years, thus permitting continuous comparisons of tendencies in design; its history being closely identified with technical progress. The 1932 exhibition is organised, as usual, by the Chambre Syndicate des Industries Aéronautiques, of which M. Henry Potez, the well‐known aeroplane and engine manufacturer, is the present President, M. André Granet being Commissaire Général.
THE Newcastle school, like most others, was established after the second world war to provide full‐time education in librarianship as an alternative to the part‐time system which…
Abstract
THE Newcastle school, like most others, was established after the second world war to provide full‐time education in librarianship as an alternative to the part‐time system which until 1946 was the only one available to the majority of librarians. At first most of the students were returning servicemen whose library careers had been interrupted by the war and they were followed by students direct from libraries, universities and schools. From a handful of students and one full‐time member of staff in the first year the school has grown steadily until there were 53 students and five staff during the session 1962–3 which was the last course held for the Registration Examination.
Patrick Moriarty and Damon Honnery
The purpose of this paper is to show that the observed strong link between global economic output and primary energy use will continue in future; and attempts to replace fossil…
Abstract
Purpose
The purpose of this paper is to show that the observed strong link between global economic output and primary energy use will continue in future; and attempts to replace fossil fuels with alternative energy sources or implementing CO2 removal or geoengineering approaches cannot provide the level of clean energy that economic growth needs. Global economic growth, therefore, is unlikely to continue for much longer.
Design/methodology/approach
The paper uses historical and recent global data (2012) for energy output from various sources, economic output and CO2, emissions to make its case.
Findings
Alternative energy output is growing too slowly, and faces too many problems, to significantly change the energy mix in the coming decades. Continued use of fossil fuels requires either massive CO2 removal/sequestration or global solar radiation management (SRM). The first is too expensive and would take decades to be significant, the second carries risks, some already known and possibly also unknown ones.
Practical implications
The paper makes the case that technical fixes such as alternative fuels, energy efficiency improvements, carbon dioxide capture and SRM will not be sufficient to prevent global climate change.
Social implications
Social change, rather than reliance on technical fixes, is needed for ecologically sustainable economies.
Originality/value
Most research argues that global energy intensity and carbon intensity will continue to fall. In contrast, we argue that the strong link observed between global economic output and primary energy use will most likely continue.
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Elisa Capello, Giorgio Guglieri and Fulvia B. Quagliotti
The purpose of this paper is to report the research activity of Politecnico di Torino concerning the MicroHawk platform (micro‐aerial vehicles – MAVs) and to present the design…
Abstract
Purpose
The purpose of this paper is to report the research activity of Politecnico di Torino concerning the MicroHawk platform (micro‐aerial vehicles – MAVs) and to present the design and the development of a basic flight simulator for educational/training purpose.
Design/methodology/approach
A simulator is an easy‐to‐use system for the analysis of maneuver response, the dynamic study and the evaluation of the aircraft flying and handling qualities for different aircraft categories. The software implementation, including the definition of mathematical model, the visual scenario and the real‐time data analysis graphic interface, are delineated in this paper. In addition to this experimental phase, an important effort is done to incorporate simulation into the autopilot tuning process.
Findings
An intense flight activity is carried out to test the flight control system performances of the MicroHawk platform and to establish general procedures to ensure the correct operation of all subsystems. The automatic flight of MAVs has been studied with success for territorial surveillance and map project.
Research limitations/implications
In order to simplify the use of these platforms by the end‐user, a software interface will be designed to calculate automatically the flight plan, ensuring the desired trajectory design and collision avoidance.
Originality/value
The autopilot simulation integrated with vehicle's dynamics can be used to reduce the platform set‐up time and the risk of losing the prototype. The simulator training permits to study flight complex plane, in order to obtain better platform performances in real conditions. Starting from a simple scenario, it is possible to set up and upgrade the mission at any time during the simulation.
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