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The purpose of this paper is to present the autopilot design for the missile under various disturbances.

In this study, model predictive control (MPC) method has been used for autopilot design for each axis. The aim of autopilot is that to keep the roll angle value around the zero degree and to track pitch/yaw acceleration commands. This three-axes control methodology also takes into consideration the interaction between pitch, yaw and roll motions.

The purpose of using MPC method for three-axes of the autopilot is to decrease the control effort and to make the close-loop system insensitive against modeling uncertainties and stochastic effects.

This study shows that the missile is able to reach to the desired target with good robustness, low control effort and little miss-distance under disturbances such as aerodynamic uncertainties, thrust misalignment and gust affect by using this alternative control method.

The purpose of this paper is to increase flight performance of small unmanned aerial vehicle (UAV) using simultaneous UAV and autopilot system design.

A small UAV is manufactured in Erciyes University, College of Aviation, Model Aircraft Laboratory. Its wing and tail is able to move forward and backward in the nose-to-tail direction in prescribed interval. Autopilot parameters and assembly position of wing and tail to fuselage are simultaneously designed to maximize flight performance using a stochastic optimization method. Results are obtained are used for simulations.

Using simultaneous UAV and autopilot system design idea, flight performance is maximized.

Permission of Directorate General of Civil Aviation in Turkey is required for testing UAVs in long range.

Simultaneous design idea is very beneficial for improving UAV flight performance.

Creating a novel method to improve flight performance of UAV and developing an algorithm performing simultaneous design idea.

The purpose of this paper is to rise the autonomous flight performance of the small unmanned aerial vehicle (UAV) using simultaneous tailplane of UAV and autopilot system design.

A small UAV is remanufactured in the UAV laboratory. Its tailplane can be changed before the flight. Autopilot parameters and some parameters of tailplane are instantaneously designed to maximize autonomous flight performance using a stochastic optimization method. Results found are applied for simulations.

Benefitting simultaneous tailplane of UAV and autopilot system design process, autonomous flight performance is maximized.

Authorization of Directorate General of Civil Aviation in Turkey is required for UAV flights.

Simultaneous tailplane and autopilot system design process is so useful for refining UAV autonomous flight performance.

Simultaneous tailplane and autopilot system design process fulfills confidence, high autonomous performance, and easy service demands of UAV users. By that way, UAV users will be able to use better UAVs.

Creating a novel technique to recover autonomous flight performance (e.g. less overshoot, less settling time and less rise time during trajectory tracking) of UAV and developing a novel procedure performing simultaneous tailplane of UAV and autopilot system design idea.

The purpose of this paper is to apply a factorization‐based control system design procedure to design of auto‐pilot systems.

The design approach is based on a previously developed factorization‐based control system design procedure. The design approach requires a stable coprime factorization of the plant, a set of stable coprime factors that are solutions to the Bezout identity, the linear model of a desired response, and the desired frequency range of interest. When all this information is provided, the developed automated software outputs a candidate auto‐pilot whose performance should be verified.

For a specific class of aerospace vehicles, it is found that the described factorization‐based auto‐pilot design procedure may replace the presently complicated auto‐pilot design procedures. The final design is simpler than other techniques that are based on classical, robust, adaptive, QFT, gain scheduling, or interpolation techniques, and the total required man hours for the design loop is less than the mentioned alternative approaches.

There are two basic limitations – time variations of plant parameters must not be very large as is the case with the agile aerospace vehicles, and specification of the desired closed‐loop system behavior is not systematic.

The major outcome of this research is that complicated autopilots of a class of aerospace vehicles may be replaced by simpler systems with competitive performance.

This is the first paper in the area of autopilot design that is based on the application of a simple factorization‐based design procedure.

The purpose of this paper is to design a robust angle-of-attack (AOA) tracking control system for the hypersonic reentry vehicle (HRV) based on the linear parameter varying (LPV) theory, as the aerodynamic coefficients of the hypersonic vehicle vary quickly during the reentry phase.

First, longitudinal moment trim is done along the desired flight trajectory. The linearized system at each trim point is built and the dynamic characteristics analysis is made. Then the LPV control law with parameter-dependent quadratic Lyapunov function (PDQLF-LPV) is applied to design the AOA tracking autopilot at each trim point. Frequency performance of the autopilot is assessed and the step response simulation is conducted to validate the effectiveness of the control system. Finally, actual AOA command tracking simulations based on the time-varying nonlinear model are carried out to test the correctness and robustness of the PDQLF-LPV autopilot.

Analysis results demonstrate that the PDQLF-LPV control system can track the AOA command perfectly during the whole flight envelop with dynamics parameter variation or disturbances, which indicates that it is effective to integrate the PDQLF-LPV control theory with a parameter-varying reference model for control system design of HRV.

A reference model with varying parameters is utilized to guarantee the transient performance of the autopilot, and induced L2-norm analysis is introduced to describe and guarantee the robust stability of the autopilot.

This paper aims to investigate the autonomous performance optimization of a research-based hybrid unmanned aerial vehicle (i.e. HUAV) manufactured at Iskenderun Technical University.

To maximize the autonomous performance of this HUAV, longitudinal and lateral dynamics were initially obtained. Then, the optimum magnitudes of the autopilot system parameters were estimated by considering the vehicle’s dynamic model and autopilot parameters.

After determining the optimum values of the longitudinal and lateral autopilots, an improved design for the autonomously controlled (AC) HUAV was achieved in terms of real-time flight.

Simultaneous improvement of the longitudinal and lateral can be used for better HUAV operations.

In this paper, the autopilot systems (i.e. longitudinal and lateral) of an HUAV are for the first time simultaneously designed in the literature. This helps the simultaneous improvement of the longitudinal and lateral flight trajectory tracking performances.

The purpose of this paper is to design linear quadratic regulator (LQR) based Luenberger observer for the estimation of unknown states of aircraft.

In this paper, the LQR-based Luenberger observer is deliberated for autonomous level flight of unmanned aerial vehicle (UAV) which has been attained productively. Various modes like phugoid and roll modes are exploited for controlling the rates of UAV. The Luenberger observer is exploited for estimation of the mysterious states of the system. The rates of roll, yaw and pitch are used as an input to the observer, while the remaining states such as velocities and angles have been anticipated. The main advantage of using Luenberger observer was to reduce the cost of the system which has been achieved lucratively. The Luenberger observer proposes sturdiness at the rate of completion to conquest over the turmoil and insecurities to overcome the privileged recital. The FlightGear simulator is exploited for the endorsement of the recital of the Luenberger observer-based autopilot. The level flight has been subjugated lucratively and has been legitimated by exploiting the FlightGear simulator. The authenticated and the validated results are offered in this paper. Microsoft Visual Studio has been engaged as a medium between the MATLAB and FlightGear Simulator.

The suggested observer based on LQR ensures the lucrative approximation of the unknown states of the system as well as the successful level flight of the system. The Luenberger observer is used for approximation of states while LQR is used as controller.

In this research work, not only the estimation of unknown states of both longitudinal and lateral model is made but also the level flight is achieved by using those estimated states and the autopilot is validated by using the FlightGear, while in most of the research work only the estimation is made of only longitudinal or lateral model.

The purpose of this paper is to improve autonomous flight performance of an unmanned aerial vehicle (UAV) having actively sweep angle morphing wing using simultaneous UAV and flight control system (FCS) design.

An UAV is remanufactured in the ISTE Unmanned Aerial Vehicle Laboratory. Its wing sweep angle can vary actively during flight. FCS parameters and wing sweep angle are simultaneously designed to optimize autonomous flight performance index using a stochastic optimization method called as simultaneous perturbation stochastic approximation (SPSA). Results obtained are applied for flight simulations.

Using simultaneous design process of an UAV having actively sweep angle morphing wing and FCS design, autonomous flight performance index is maximized.

Authorization of Directorate General of Civil Aviation in Turkey is crucial for real-time UAV flights.

Simultaneous UAV having actively sweep angle morphing wing and FCS design process is so beneficial for recovering UAV autonomous flight performance index.

Simultaneous UAV having actively sweep angle morphing wing and FCS design process achieves confidence, high autonomous performance index and simple service demands of UAV operators.

Composing a novel approach to improve autonomous flight performance index (e.g. less settling and rise time, less overshoot meanwhile trajectory tracking) of an UAV and creating an original procedure carrying out simultaneous UAV having actively sweep angle morphing wing and FCS design idea.

The purpose of this paper is to design an integrated guidance and control design for a formation flight of four unmanned aerial vehicles to follow a moving ground target.

The guidance law is based on the line‐of‐sight. The control is optimal. The guidance law is integrated with the optimal control law and is applied to a linear dynamic model.

The theoretical results are supported by the numerical simulations that illustrate a coordinated encirclement of a ground maneuvering target.

A linear dynamic UAV model and a liner engine model were employed.

This is expected to provide efficient coordination technique required in many civilian circular formation UAV applications; also the technique can be used to provide a safe environment required for the civil applications.

The research will facilitate the deployment of autonomous unmanned aircraft systems in various civilian applications such as border monitoring.

The research addresses the challenges of coordination of multiple unmanned aerial vehicles in a circular formation using an integrated optimal control technique with line‐of‐sight guidance.

The guided missile system is considered as SISO plant with parameter perturbations. The structure of the missile system is not suitable for the use of classical linear controllers. On the other hand, the missile system should be capable of good performances, such as zero steady state error, less settling time etc. Standard VSC control laws fail to control the steady state error due to the structure of the system matrices. For this reason we have proposed two new robust output integral sliding mode controllers and design procedures. An integrator is included in the sliding function, which results in the reduction and removal of the output error. The total control consists of two parts: equivalent control which compensates the nominal regime of the missile system; and VSC which compensates the parameter perturbations (changes in Mach number, altitude and mass of the vehicle, etc.) of the missile system. We have derived new constructive sliding and stability conditions for both cases by using Lyapunov’s direct method. Computer simulations indicate that this approach yields a satisfactory control performance.