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The purpose of this paper is to give reviews on the platform modeling and design of a controller for autonomous vertical take-off and landing (VTOL) tilt rotor hybrid unmanned aerial vehicles (UAVs). Nowadays, UAVs have experienced remarkable progress and can be classified into two main types, i.e. fixed-wing UAVs and VTOL UAVs. The mathematical model of tilt rotor UAV is time variant, multivariable and non-linear in nature. Solving and understanding these plant models is very complex. Developing a control algorithm to improve the performance and stability of a UAV is a challenging task.

This paper gives a thorough description on modeling of VTOL tilt rotor UAV from first principle theory. The review of the design of both linear and non-linear control algorithms are explained in detail. The robust flight controller for the six degrees of freedom UAV has been designed using H-infinity optimization with loop shaping under external wind and aerodynamic disturbances.

This review will act as a basis for the future work on modeling and control of VTOL tilt rotor UAV by the researchers. The development of self-guided and fully autonomous UAVs would result in reducing the risk to human life. Civil applications include inspection of rescue teams, terrain, coasts, border patrol buildings, police and pipelines. The simulation results show that the controller achieves robust stability, good adaptability and robust performance.

The review articles on quadrotors/quadcopters, hybrid UAVs can be found in many literature, but there are comparatively a lesser amount of review articles on the detailed description of VTOL Tilt rotor UAV. In this paper modeling, platform design and control algorithms for the tilt rotor are presented. A robust H-infinity loop shaping controller in the presence of disturbances is designed for VTOL UAV.

This paper aims to address shortcomings of current tiltrotor designs, such as the small aspect ratio of the wings, large download and the close proximity of the rotor tips. It also aims to avoid the complex transition of tiltrotors to normal airplane mode.

This design combines tiltrotor and tiltwing aircraft designs into a hybrid that is augmented by active flow control, using a gimbaled channel wing for attitude control in hover.

The proposed hybrid design is based on experimental results of components that were tested individually for potential use in hover and steep ascend from a stationary position.

This research was inspired by the extremely short take-off of the V-22, when its rotors were tilted forward. It combines several design approaches in a unique way to achieve extremely short take-off capabilities combined with high-speed and reduced maintenance costs.

The 100th Foxhunter air interception radar has been delivered to RAF Coningsby in Lincolnshire for the RAF's top fighter aircraft — the Tornado Air Defence Variant (ADV).

ONE has only to look at the achievements of the past decade to realise the strength and the vast scope of the American aerospace industry. In the Western world it has no challengers, and in the space race Russia, after a head start, had to be content with sending a robot spacecraft to the moon. The Apollo programme, initiated by President Kennedy, was a near miracle of precision engineering, backed by a fantastically complex support operation. It worked.

The purpose of this paper is to study the conceptual design and optimisation of a compound gyroplane. A study of a compound gyroplane configuration and its characteristics was performed to develop a sizing program.

The vertical takeoff and landing capabilities of a helicopter are particularly important. The need for efficient hover and the effectiveness of forward flight in the helicopter can cause conflicts within the design process. The designers usually wish to increase the helicopter's maximum forward speed. Recently, the compound aircraft is one of the concepts considered for the purpose of expanding the flight envelope of rotorcraft. The study of the compound gyroplane showed its advance capabilities for this purpose. Understanding its characteristics, a number of calculations are conducted to implement a sizing program for compound gyroplanes based on the conventional helicopter sizing process.

The results of the sizing program were validated using existing aircraft data such as the Challis Heliplane, Carter Copter, FB‐1 Gyrodyne, and Jet Gyrodyne. The program is appropriate to size a compound gyroplane at the conceptual design phase. An optimisation study was also performed to enhance sizing results. The compromise between the rotor lift sharing factor and the ratio of the wing span (Bw) to rotor diameter (D) was solved by choosing the total gross weight (TOGW) as the objective function, while the design variables are compromising factors. The optimum results showed that the TOGW of all four kinds of compound gyroplanes was considerably reduced.

A conceptual sizing program for unconventional compound aircraft was developed. The study showed that an optimum design process is necessary to enhance the sizing results.

PICTURE THE CORPORATE HELICOPTER MARKET as a giant iceberg. It represents our accomplishments to date and also is the key to our future, provided we adjust our marketing methods.

This paper aims to present an investigation on flight quality analysis and design of tilt-rotor aircraft combined with corresponding flight quality specifications.

From the perspective of modal characteristics of tilt-rotor aircraft, it focuses on the analysis of the change rules of the longitudinal short-term motion mode, lateral roll convergence mode, spiral mode and Dutch roll mode. Then, the flight quality design research is carried out using the explicit model tracking control method. The quantitative relationship between flight quality requirements and explicit model is established. Accordingly, the closed-loop flight quality of XV-15 tilt-rotor aircraft is evaluated.

The stability of spiral mode is the result of the interaction of various aerodynamic derivatives and spiral instability occurs in helicopter mode. The other motion modes are stable in full flight mode and meet the requirements of level 1 specified in ADS-33E-PRF and MIL-F-8785C flight quality specifications. There is a quantitative relationship between flight quality requirements and explicit model, and the flight quality of tilt-rotor aircraft is improved through the explicit model tracking control method.

The presented analysis results showed the influence of motion modes and flight quality and the effectiveness of explicit model tracking control method in flight quality improvement, which could be considered as new information for further flight quality design of tilt-rotor aircraft.

The originality of the paper lies in the proposed design and analysis method of the flight quality of tilt-rotor aircraft from the direction of the influence of its aerodynamic derivatives and motion modes.

Tilt rotor aircraft will add new dimensions to corporate and charter air transportation beginning in the 1980s or 1990s. The tilt rotor combines the VTOL capability of the helicopter with the speed, range, and fuel economy of the turboprop aircraft. The civil use of he helicopter has expanded enormously in the last 25 years because of its effectiveness in point‐to‐point transportation and its capability to operate from confined or limited areas. The tilt rotor dramatically increases that effectiveness because it hovers like a helicopter but cruises at twice the speed for twice the range on the same amount of fuel.

The purpose of this article is to evaluate performance of minimum energy controllers thoroughly on a tiltrotor aircraft.

Minimum energy controllers are designed for tiltrotor aircraft models for helicopter and airplane modes. Performance of minimum energy controllers is evaluated with respect to several criteria.

Minimum energy controllers can be used for tiltrotor aircraft flight control system design. These controllers show satisfactory performance when noise intensities and variance bounds vary.

Minimum energy controllers can be implemented for tiltrotor aircraft flight control system design.

In this paper, minimum energy controllers are applied for tiltrotor aircraft flight control system design and the performance of minimum energy controllers is evaluated deeply on a complex physical system (i.e. tiltrotor aircraft).

This paper aims to present the results of aerodynamic calculation of the aircraft in tandem wing configuration called VTOL. A presented vehicle combines the capabilities of the classic aircraft and helicopters. The aircraft is equipped with two pairs of tilt-rotors mounted on the tips of the front and the rear wing. The main goal of the presented research was to find the aerodynamic impact of both pairs of tilt-rotors on aerodynamic coefficients of the aircraft. Moreover, the rotors impact on the static stability of the aircraft was investigated too.

The CFD analysis was made for the complete aircraft in the tandem wing configuration. The computation was performed for the model of aircraft which was equipped with the four sub-models of the front and rear rotors. They were modeled as the actuator discs. This method allows for computing the aerodynamic impact of rotating components on the aircraft body. All aerodynamic analysis was made by the MGAERO software. The numerical code of the software was based on the Euler flow model. The used numerical method allows for the quick computation of very complex model of aircraft with a satisfied accuracy.

The result obtained by computation includes the aerodynamic coefficients which described the impact of the tilt rotors on the aircraft aerodynamic. The influence of the angle of attack, sideslip angle and the change of rotor tilt angle was investigated. Evaluation of the influence was made by the stability margin analysis and the selected stability derivatives computation.

Presented results could be very useful in the computation of dynamic stability of unconventional aircraft. Moreover, results could be helpful during designing the aircraft in the tandem wing configuration.

This paper presents the aerodynamic analysis of the unconventional configuration of the aircraft which combines the tandem wing feature with the tilt-rotor advantages. The impact of disturbance generated by the front and rear rotors on the flow around the aircraft was investigated. Moreover, the impact of rotors configuration on the aircraft static stability was found too.