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Spinning slender bodies are affected by lateral Magnus forces and moments when exposed to cross-flow. The effects occurring for spinning bodies of revolution in combination with stabilising or control surfaces such as canards are not yet fully explained. Therefore the present work aims to investigate the phenomena arising from the interactions of a roll-decoupled guidance unit with a spinning rear body are investigated.

A generic tangential-ogive-cylinder projectile equipped with deflectable canards on a roll-decoupled nose is investigated by means of 3D Reynolds-averaged Navier–Stokes simulations at Mach number 2 for angles of attack up to 22 degrees. Different canard deflection angles up to 9 degrees are considered. Global aerodynamic coefficients as well as local flow fields are analysed to explain the interactions occurring between the roll-decoupled guidance unit and the spinning rear body.

The deflected canards lead to flow interactions resulting in lateral forces and moments even without a spinning motion of the rear part. Depending on the canard deflection angles, these forces act in or against the direction of the classical Magnus effect. For angles of attack smaller than 10 degrees it is possible for the current body geometry to directly superpose the lateral effects resulting from the fins for the non-spinning model with those occurring for the non-finned but spinning model to obtain the total forces and moments acting on a spinning model with canted canards. However, the lateral effects generated on the guidance unit itself are insignificant compared to the canard-induced effects on the rear body.

A detailed analysis of the interaction effects arising from a decoupled guidance unit containing canards with a non-spinning/spinning rear body is performed and the underlying phenomena are revealed.

The purpose of this paper is to mount Gurney flaps at the trailing edges of the canards and investigate their influence on aerodynamic characteristics of a simplified canard-configuration aircraft model.

A force measurement experiment was conducted in a low-speed wind tunnel. Hence, the height and shape effects of the Gurney flaps on the canards were investigated.

Gurney flaps can increase the lift and pitching-up moment for the aircraft model tested, thereby increasing the lift when trimming the aircraft. The dominant parameter to influence aerodynamic characteristics is the height of Gurney flaps. When the flap heights are the same, the aerodynamic efficiency of the triangular Gurney flaps is higher than that of the rectangular ones. Moreover, the canard deflection efficiency will be reduced with Gurney flaps equipped, but the total aerodynamic increment is considerable.

This paper helps to solve the key technical problem of increasing take-off and landing lift coefficients, thus improving the aerodynamic performance of the canard-configuration aircraft.

This paper recommends to adopt triangular Gurney flaps with the height of 3 per cent chord length of the canard root (c) for engineering application.

This paper aims to analyze the influence of the changings in geometrical parameters on the aerodynamic performance of the control canard projectiles.

Because of the mentioned point, the range of projectiles increment has a considerable importance, and the design algorithm of a control canard projectile was first written. Then, were studied the effects of canard geometric parameters such as aspect ratio, taper ratio and deflectable nose on lift to drag coefficient ratio, static margin based on the slender body theory and cross section flow.

The code results show that aspect ratio increment, results in an increase in lift-to-drag ratio of the missile, but increase in canard taper ratio results in increasing of lift-to-drag ratio at 1° angle of attack, while during increasing the canard taper ratio up to 0.67 at 4° angle of attack, lift to drag first reaches to maximum and then decreases. Also, static margin decreases with canard taper ratio and aspect ratio increment. The developed results for this type of missile were compared with same experimental and computational fluid dynamic (CFD) results and appreciated agreement with other results at angles of attack between 0° and 6°.

To design a control canard missile, the effect of each geometric parameter of canard needs to be estimated. For this purpose, the suitable algorithm is used. In this paper, the effects of canard geometric parameters, such as aspect ratio, taper ratio and deflectable nose on lift-to-drag coefficient ratio and static margin, were studied with help of the slender body theory and cross-section flow.

The contribution of this paper is to predict the aerodynamic characteristics for the control canard missile. In this study, the effect of the design parameter on aerodynamic characteristics can be estimated, and the effect of geometrical characteristics has been analyzed with a suitable algorithm. Also, the best lift-to-drag coefficient for the NASA Tandem Control Missile at Mach 1.75 was selected at various angles of attack. The developed results for this type of missile were compared with same experimental and CFD results.

The purpose of this paper is to design a new method to realize automatic assembly of aircraft components with large shafts such as canard and vertical tail. The assembly structure of component with large shaft and fuselage is a mating assembly structure, and it is a challenge to satisfy the precision and assembly requirement.

According to the assembly structure features and process requirements of an aircraft component with large shaft, the operating principle of precise assembly system for shaft-hole mating is analyzed in this paper. The model of compliant assembly for shaft-hole mating is constructed, and force condition analysis of the compliant assembly is performed. An automatic precise shaft-hole assembly method for aircraft assembly using 5 degrees of freedom spatial mechanism, compliance technology and servo feeding system is put forward based on the analysis. A 5 degrees of freedom passive compliant experimental equipment has been developed.

Application test results of the 5 degrees of freedom passive compliant experimental equipment show that the simulated canard can be mated automatically and accurately through this method with high efficiency and high quality as long as the tip of shaft enters into the range of hole’s chamfer.

This method has been used in an aircraft assembly project. The practical results show that the aircraft components with large shafts can be mated automatically and accurately through this method with high efficiency and high quality.

This paper presents a new method and designs a new assembly system to realize the assembly of the aircraft components with large shafts. The research will promote the automation of fuselage assembly.

This paper aims to describe the use of optimization approaches to increase the range of near-future howitzer ammunition.

The performance of a gliding projectile concept is assessed using an aeroballistic workflow, comprising aerodynamic characterization and flight trajectory computation. First, a single-objective optimization is run with genetic algorithms to find the maximal attainable range for this type of projectile. Then, a multi-objective formulation of the problem is proposed to consider the compromise between range and time of flight. Finally, the aerodynamic model used for the gliding ammunition is evaluated, in comparison with direct computational fluid dynamics (CFD) computations.

Applying single-objective range maximization results in a great improvement of the reachable distance of the projectile, at the expense of the flight duration. Therefore, a multi-objective optimization is implemented in a second time, to search sets of parameters resulting in an optimal compromise between fire range and flight time. The resulting Pareto front can be directly interpreted and has the advantage of being useful for tactical decisions.

The main limitation of the work concerns the aerodynamic model of the gliding ammunition, which was initially proposed as an alternative to reduce significantly the computational cost of aerodynamic characterization and enable optimizations. When compared with direct CFD computations, this method appears to induce an overestimation of the range. This suggests future evolution to improve the accuracy of this approach.

To the best of the authors’ knowledge, this paper presents an original ammunition concept for howitzers, aiming at extending the range of fire by using lifting surfaces and guidance. In addition, optimization techniques are used to improve the range of such projectile configuration.

Currently undergoing NASA flight testing is the Grumman X‐29 forward swept wing (FSW) demonstrator aircraft which was built under a contract sponsored by the Defence Advanced Research Projects Agency (DARPA) and funded through the Air Force. The FSW aircraft first took to the air in December, 1984 and after four flights with the manufacturer was handed over to NASA for a verification programme involving all the benefits of this design. Advanced technology features which will be demonstrated are the forward swept wing for improved aerodynamic efficiency and good control at high angles of attack; tailored composite wing structure that resists the tendency towards structural divergence inherent in this configuration; thin supercritical aerofoil for improved transonic performance at high lift coefficients; variable camber trailing edge to reduce drag at all lift coefficients and avoid supersonic drag associated with aerofoil camber; canard longitudinal control for efficient trimming of variable camber pitching moments and favourable canard‐wing interactions; highly relaxed static stability for very low trim drag at all Mach numbers; and a digital fly‐by‐wire flight control system.

This paper aims to investigate the singular Hopf bifurcation and mixed mode oscillations (MMOs) in the perturbed Bonhoeffer-van der Pol (BVP) circuit. There is a singular periodic orbit constructed by the switching between the stable focus and large amplitude relaxation cycles. Using a generalized fast/slow analysis, the authors show the generation mechanism of two distinct kinds of MMOs.

The parametric modulation can be used to generate complicated dynamics. The BVP circuit is constructed as an example for second-order differential equation with periodic perturbation. Then the authors draw the bifurcation parameter diagram in terms of a containing two attractive regions, i.e. the stable relaxation cycle and the stable focus. The transition mechanism and characteristic features are investigated intensively by one-fast/two-slow analysis combined with bifurcation theory.

Periodic perturbation can suppress nonlinear circuit dynamic to a singular periodic orbit. The combination of these small oscillations with the large amplitude oscillations that occur due to canard cycles yields such MMOs. The results connect the theory of the singular Hopf bifurcation enabling easier calculations of where the oscillations occur.

By treating the perturbation as the second slow variable, the authors obtain that the MMOs are due to the canards in a supercritical case or in a subcritical case. This study can reveal the transition mechanism for multi-time scale characteristics in perturbed circuit. The information gained from such results can be extended to periodically perturbed circuits.

The purpose of this paper is to describe the new method for optimizing the topology of the control system frame for a canard missile to create its efficient model. Determining the minimum volume of the part risked losing some of the mechanical interfaces and functionality required of the frame. The proposed method must cope with these requirements and include a validation loop of the improved solution proposed by the software. The processing of the mathematical model to a printable form must take into account manufacturing technologies limitations and appropriate curvature continuities to avoid stress concentrations.

Real examples from the aerospace industry are presented and the process of determining a prototype is described. The optimization assumed leaving the largest volume of the domain. Strength analyses were performed on both the assembly fasteners and the robust prototype. Once all boundary conditions were validated, topological optimization was performed in the ANSYS environment. The algorithm of the optimization was presented.

Obtained fatigues showed the vast potential of topology optimization, efficient method of weight reduction in specific situations. It can be considered as an innovative approach to the manufacturing of products with a structure focused on the best possible correlation of weight and strength, for example of a canard rocket.

The paper introduces precise manufacturing technology of the inner frame for the missile’s control system, which ensures sufficient properties of the material, known as EBM.

THE type of aircraft which is now called the “Ente” is characterised by the fact that, in contrast to the normal aeroplane with a tail, it has an elevator in front of the main supporting surfaces. The attempt to build such aeroplanes is not new, but dates back to the early days of flying. One of the first flights in Europe by Santos Dumont was made with a biplane of the “Ente” type; other examples being the aero‐planes of 1910 and 1911 of Professor Reissner of Germany, and of Voisin. It was the latter who gave the “Ente” its name (Canard). These attempts have, however, sunk into oblivion for reasons quite unconnected with the principle.