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This paper aims to describe the concept of morphing tailless aircraft with discontinuous skin and its preliminary kinematic solution. Project assumptions, next steps and expected results are briefly presented.

Multidisciplinary numerical optimization will be used to determine control allocation for wing segments rotation. Wing demonstrator will be fabricated and tested in wind tunnel. Results will be used in construction of flying model and design of its control system. Flight data of morphing demonstrator and reference aircraft will result in comparative analysis of both technologies.

Proposed design combines advantages of wing morphing without complications of wing’s structure elastic deformation. Better performance, stability and maneuverability is expected due to wing’s construction which is entirely composed of unconnected wing segments. Independent control of each segment allows for free modeling of spanwise lift force distribution.

Nonlinear multipoint distribution of wing twist as the only mechanism for control and flight performance optimization has never been studied or constructed. Planned wind tunnel investigation of such complex aerodynamic structure has not been previously published and will be an original contribution to the development of aviation and in particular to the aerodynamics of wing with discontinuous skin.

The purpose of this paper is to demonstrate the uncontrolled vertical takeoff of an insect-mimicking flapping-wing micro air vehicle (FW-MAV) of 12.5 cm wing span with a body weight of 7.36 g after installing batteries and power control.

The forces were measured using a load cell and estimated by the unsteady blade element theory (UBET), which is based on full three-dimensional wing kinematics. In addition, the mean aerodynamic force center (AC) was determined based on the UBET calculations using the measured wing kinematics.

The wing flapping frequency can reach to 43 Hz at the flapping angle of 150°. By flapping wings at a frequency of 34 Hz, the FW-MAV can produce enough thrust to over its own weight. For this condition, the difference between the estimated and average measured vertical forces was about 7.3 percent with respect to the estimated force. All parts for the FW-MAV were integrated such that the distance between the mean AC and the center of gravity is close to zero. In this manner, pitching moment generation was prevented to facilitate stable vertical takeoff. An uncontrolled takeoff test successfully demonstrated that the FW-MAV possesses initial pitching stability for takeoff.

This work has successfully demonstrated an insect-mimicking flapping-wing MAV that can stably takeoff with initial stability.

The aim of this paper is to investigate the effect of wing kinematics change on force generation produced by flapping wings.

Forces produced by flapping wings are measured using a load cell and compared for the investigation. The measured forces are validated by estimation using an unsteady blade element theory.

From the measurement and estimation, the authors found that flapping wings produced positive and negative lifts when the wings are attached with the +30° and −30°, respectively.

The authors quantified the characteristics of change in the force generation by flapping wings for three wing kinematics. The wing kinematics was modified by changing the initial wing attachment angle.

The result may be applicable to design of control mechanism for an insect‐mimicking flapping‐wing micro air vehicle, which has only wings without control surfaces at its tail.

The preliminary work may provide an insight for design strategy of flapping‐wing micro air vehicles with compact and handy configurations, because they may perform controlled flight even without control surfaces at their tails.

The work included here is the first attempt to quantify the force generation characteristics for different wing kinematics. The suggested way of wing kinematics change can provide a concept for control mechanism of a flapping‐wing micro air vehicle.

THE OBJECTIVES of this article are twofold, firstly to argue the case for variable configuration aircraft, i.e. aircraft whose planform can be adjusted in flight to give optimum performance in differing roles; and secondly, to put forward proposals for a wing suspension designed to overcome the handicaps inherent in the method so far employed in mounting the wings of variable configuration aircraft.

THE primary duties of an aircraft design team are to design an aircraft capable of meeting a certain specification of performance and manoeuvrability with suitable flying qualities, and to ensure that it will be strong enough to withstand any aerodynamic loads it may suffer in flight. It will be found that the aircraft when built is not a rigid structure, but this in itself is not important. We are all familiar with the flexing of an aircraft's wings when struck by a sharp gust of wind in flight, but as long as the wings are strong enough no harm is done. On the contrary, in a passenger aircraft the flexibility of the wings in bending will have a favourable effect, as it will cushion the passengers to some extent from the suddenness of the gust. Flexibility of the structure, however, is not always beneficial and it often introduces new difficulties in the designer's problems. These difficulties arise when the deformation of the aircraft structure introduces additional aerodynamic forces of appreciable magnitude. The additional forces will themselves cause deformation of the structure which may introduce still further aerodynamic forces, and so on. It is interactions of this type between elastic and aerodynamic forces which lead to the oscillatory phenomenon of flutter, and to the non‐oscillatory phenomena of divergence and reversal of control. The study of these three aero‐elastic problems becomes more important as aircraft speeds increase, because increase of design speeds leads to more slender aircraft with thinner wings, and therefore to relatively greater flexibility of the structure. The dangers, in fact, are such that the designers of a modern high‐performance aircraft have to spend considerable effort on the prediction of aero‐elastic effects in order that suitable safeguards can be included in the design. By far the greatest part of this effort is spent on flutter, which will be discussed in Parts II, III and IV of this series, but any of the three problems may force the designers to increase the structural stiffness of parts of the aircraft. The wing skin thickness on a modern aircraft, for example, is nearly always designed by consideration either of aileron reversal or wing flutter. Divergence is usually less important but as it is the simplest of the three phenomena to treat analytically, we shall study it first.

The purpose of this paper is to present an approach to employ evolvable hardware concepts, to effectively construct flapping‐wing mechanism controllers for micro robots, with the evolved dynamically complex controllers embedded in a, physically realizable, micro‐scale reconfigurable substrate.

In this paper, a continuous time recurrent neural network (CTRNN)‐evolvable hardware (a neuromorphic variant of evolvable hardware) framework and methodologies are employed in the process of designing the evolution experiments. CTRNN is selected as the neuromorphic reconfigurable substrate with most efficient Minipop Evolutionary Algorithm, configured to drive the evolution process. The uniqueness of the reconfigurable CTRNN substrate preferred for this study is perceived from its universal dynamics approximation capabilities and prospective to realize the same in small area and low power chips, the properties which are very much a basic requirement for flapping‐wing based micro robot control. A simulated micro mechanical flapping insect model is employed to conduct the feasibility study of evolving neuromorphic controllers using the above‐mentioned methodology.

It has been demonstrated that the presented neuromorphic evolvable hardware approach can be effectively used to evolve controllers, to produce various flight dynamics like cruising, steering, and altitude gain in a simulated micro mechanical insect. Moreover, an appropriate feasibility is presented, to realize the evolved controllers in small area and lower power chips, with available fabrication techniques and as well as utilizing the complex dynamics nature of CTRNNs to encompass various controls ability in a architecturally static hardware circuit, which are more pertinent to meet the constraints of micro robot construction and control.

The proposed neuromorphic evolvable hardware approach along with its modules intact (CTRNNs and Minipop) can provide a general mechanism to construct/evolve dynamically complex and optimal controllers for flapping‐wing mechanism based micro robots for various environments with least human intervention. Further, the evolved neuromorphic controllers in simulation study can be successfully transferred to its hardware counterpart without sacrificing its anticipated functionality and realized within a predictable area and power ranges.

The purpose of this paper was to solve the shortage of carrying energy in probing robot and make full use of wind resources in the Antarctic expedition by designing a four-wheel land-yacht. Land-yacht is a new kind of mobile robot powered by the wind using a sail. The mathematical model and trajectory of the land-yacht are presented in this paper.

The mechanism analysis method and experimental modeling method are used to establish a dual-input and dual-output mathematical model for the motion of land-yacht. First, the land-yacht’s model structure is obtained by using mechanism analysis. Then, the models of steering gear, servomotors and force of wing sail are analyzed and validated. Finally, the motion of land-yacht is simulated according to the mathematical model.

The mathematical model is used to analyze linear motion and steering motion. Compared with the simulation results and the actual experimental tests, the feasibility and reliability of the proposed land-yacht modeling are verified. It can travel according to the given signal.

This land-yacht can be used in the Antarctic, outer planet or for harsh environment exploration.

A land-yacht is designed, and the contribution of this research is the development of a mathematical model for land-yacht robot. It provides a theoretical basis for analysis of the land-yacht’s motion.

The purpose of this study is to experimentally analyse the effect of flexible and stiffened membrane wings in the lift generation of flapping micro air vehicle (MAV).

This is analysed by the rectangle wing made up of polyethylene terephthalate sheets of 100 microns. MAV is tested for the free stream velocity of 2 m/s, 4 m/s, 6 m/s and k^* of 0, 0.25, 1, 3, 8. This test is repeated for flapping MAV of the free flapping frequency of 2 Hz, 4 Hz, 6 Hz, 10 Hz and 12 Hz.

This study shows that the membrane wing with proper stiffeners can give better lift generation capacity than a flexible wing.

Only a normal force component is measured, which is perpendicular to the longitudinal axis of the model.

In MAVs, the wing structures are thin and light, so the effect of fluid-structure interactions is important at low Reynold’s numbers. This data are useful for the MAV developments.

The effect of chord-wise flexibility in lift generation is the study of the effect of a flexible wing and rigid wing in MAV. It is analysed by the rectangle wing. The coefficient of normal force at different free stream conditions was analysed.

Under this heading are published regularly abstracts of all Reports and Memoranda of the Aeronautical Research Committee, Reports and Technical Notes of the U.S. National Advisory Committee for Aeronautics and publications of other similar research bodies as issued

Major technical advances were featured at the Show, particularly those developments that will be coming into service in the very near future. An outstanding demonstration was given by the Airbus Industrie A 300B2 Fly‐By‐Wire (FBW) whose autopilot simulates the control laws of the A 320. The pilot flies the aircraft through the FBW autopilot using the sidestick controllers as in the A 320, which is due to make its first flight in March, 1987. A convincing display by the A 300 FBW began with a slow fly‐past in landing configuration with gear and flaps down at a speed of about 100 knots. At mid‐runway position, the crew simulate a windshear encounter and the captain pulls back on the stick as might happen in such a situation. In a standard ‘conventional’ aircraft, this would lead to a stall with potentially disastrous consequences, but with FBW the pitch angle increases to the point where the wing reaches its maximum lift position and stays there. The ‘alpha‐floor’ protection incorporated in the aircraft then automatically increased engine power and the combination of maximum lift and power results in a climb‐out at 3,000ft/min. In another manoeuvre, the aircraft is positioned at an angle of attack of 15.5° in order to stabilise speed at 95–100 knots and only just below the limit of 17° — 18°. Also demonstrated was a stall turn with the nose up to maximum angle of attack and bank angle of 30° which stops there despite the fully‐deflected stick position. The engine power in this manoeuvre is controlled manually.