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The purpose of this paper is to develop a theoretical design for the attitude control of electromagnetic formation flying (EMFF) satellites, present a nonlinear controller for the relative translational control of EMFF satellites and propose a novel method for the allocation of electromagnetic dipoles.

The feedback attitude control law, magnetic unloading algorithm and large angle manoeuvre algorithm are presented. Then, a terminal sliding mode controller for the relative translation control is put forward and the convergence is proved. Finally, the control allocation problem of electromagnetic dipoles is formulated as an optimization issue, and a hybrid particle swarm optimization (PSO) – sequential quadratic programming (SQP) algorithm to optimize the free dipoles. Three numerical simulations are carried out and results are compared.

The proposed attitude controller is effective for the sun-tracking process of EMFF satellites, and the magnetic unloading algorithm is valid. The formation-keeping scenario simulation demonstrates the effectiveness of the terminal sliding model controller and electromagnetic dipole calculation method.

The proposed method can be applied to solve the attitude and relative translation control problem of EMFF satellites in low earth orbits.

The paper analyses the attitude control problem of EMFF satellites systematically and proposes an innovative way for relative translational control and electromagnetic dipole allocation.

The paper aims to address the combined attitude control and Sun tracking problem in a flexible spacecraft in the presence of external and internal disturbances. The attitude stabilization of a flexible satellite is generally a challenging control problem, because of the facts that satellite kinematic and dynamic equations are inherently nonlinear, the rigid–flexible coupling dynamical effect, as well as the uncertainty that arises from the effect of actuator anomalies.

To deal with these issues in the combined attitude and Sun tracking system, a novel control scheme is proposed based on the adaptive fuzzy Jacobian approach. The augmented spacecraft model is then analyzed and the Lyapunov-based backstepping method is applied to develop a nonlinear three-axis attitude pointing control law and the adaptation law.

Numerical results show the effectiveness of the proposed adaptive control scheme in simultaneously tracking the desired attitude and the Sun.

Reaction wheels are commonly used in many spacecraft systems for the three-axis attitude control by delivering precise torques. If a reaction wheel suffers from an irreversible mechanical breakdown, then it is likely going to interrupt the mission, or even leading to a catastrophic loss. The pitch-axis mounted solar array drive assemblies (SADAs) can be exploited to anticipate such situation to generate a differential torque. As the solar panels are rotated by the SADAs to be orientated relative to the Sun, the pitch-axis wheel control torque demand can be compensated by the differential torque.

The proposed Jacobian control scheme is inspired by the knowledge of Jacobian matrix in the trajectory tracking of robotic manipulators.

This paper aims to focus on the implementation of the integral back‐stepping control on the model of BILSAT – 1 satellite of the Turkish Scientific and Technological Research Council (TUBITAK).

The nonlinear model of the satellite is divided into three groups and the control Lyapunov function is constructed systematically. The formed closed loop system is analyzed for stability according to a recently developed stability analysis procedure and multi‐run simulations.

Since the studied model includes the dynamics of a practical reaction wheel (SSTL Type: Microwheel), the simulation results showed that the designed controllers are suitable for practical application. The torque requirement is far below the maximum torque supplied by the wheel. In addition, the system seems to be quite fast and robust against the parametric uncertainties.

Since the control system is nonlinear, the computational complexity will be an issue in practical application. The stability analysis should be improved to have more reliable information concerning the disturbance torques. Currently this analysis is performed by multi‐run simulations. An observer or estimator may also be designed in order to compute the attitudes from the gyroscope readings.

The controller designed here can be implemented on the proceeding satellite projects (foregoing BILSAT projects) by TUBITAK.

The paper provides a satellite control application of back‐stepping using a model involving modified Rodriguez parameters and reaction wheel dynamics that is not studied in the literature.

The purpose of this paper is to derive a robust nonlinear attitude control law intended for practical application.

The method of input/output feedback linearization is utilized for having a linear model and a recently developed almost disturbance decoupling (ADD) approach is adopted for designing a robust satellite attitude control (SAC) system. The kinematics of the satellite is modeled by modified Rodriguez parameters because of their continuous invertibility. The design is simulated on the model of a realistic satellite project (BILSAT‐I), which is developed by the Turkish Scientific and Technological Research Council.

The torque requirement of the operation does not exceed the maximum limit provided by the actuator. The square error levels are staying under the boundary of final global attractor, which is one of the important proofs for the successful operation of the generated ADD control law.

The ADD concept is investigated on SAC problem. By that way, simple control structures with known disturbance attenuation capability can be designed.

The general reasons for considering a fresh approach to the calculation of air‐worthiness design tail loads and associated torques due to elevator‐induced pitching manoeuvres are discussed. Then follows a description of the manoeuvre itself, elevator actions to be assumed, and the proposed method of calculating the various response quantities. The analytical treatment of Czaykowski given to the unchecked manoeuvre is extended to cover the checked case in Appendix I, Part III and a comparison is made of the two types of manoeuvre. The application of the work to auto‐pilot feed‐back failure causing hunting of the elevator control is also dealt with. The effect of aircraft size, weight, e.g. position, forward speed and altitude on the various response quantities are discussed, with particular emphasis on the importance of the manoeuvre margin. To avoid possible confusion of terms the two types of elevator‐induced manoeuvre mentioned above and discussed in this paper are defined as follows:

The purpose of this paper is to evaluate the safety of formation flying satellites, and propose a method for practical collision monitoring and collision avoidance manoeuvre.

A general formation description method based on relative orbital elements is proposed, and a collision probability calculation model is established. The formula for the minimum relative distance in the crosstrack plane is derived, and the influence of J2 perturbation on formation safety is analyzed. Subsequently, the optimal collision avoidance manoeuvre problem is solved using the framework of linear programming algorithms.

The relative orbital elements are illustrative of formation description and are easy to use for perturbation analysis. The relative initial phase angle between the in‐plane and cross‐track plane motions has considerable effect on the formation safety. Simulations confirm the flexibility and effectiveness of the linear programming‐based collision avoidance manoeuvre method.

The proposed collision probability method can be applied in collision monitoring for the proximity operations of spacecraft. The presented minimum distance calculation formula in the cross‐track plane can be used in safe configuration design. Additionally, the linear programming method is suitable for formation control, in which the initial and terminal states are provided.

The relative orbital elements are used to calculate collision probability and analyze formation safety. The linear programming algorithms are extended for collision avoidance, an approach that is simple, effective, and more suitable for on‐board implementation.

This paper aims to present the idea of an automatic control system dedicated to small manned and unmanned aircraft performing manoeuvres other than those necessary to perform a so-called standard flight. The character of these manoeuvres and the range of aircraft flight parameter changes restrict application of standard control algorithms. In many cases, they also limit the possibility to acquire complete information about aircraft flight parameters. This paper analyses an alternative solution that can be applied in such cases. The loop manoeuvre, an element of aerobatic flight, was selected as a working example.

This paper used theoretical discussion and breakdowns to create basics for designing structures of control algorithms. A simplified analytical approach was then applied to tune regulators. Research results were verified in a series of computer-based software-in-the-loop rig test computer simulations.

The structure of the control system enabling aerobatic flight was found and the method for tuning regulators was also created.

The findings could be a foundation for autopilots working in non-conventional flight scenarios and automatic aircraft recovery systems.

This paper presents the author’s original approach to aircraft automated control where high precision control is not the priority and flight parameters cannot be precisely measured or determined.

Emphasises the dangers of complacency in business thinking and of the risks associated with strategic decisions that are repetitive and predictable. Introduces a military decision making model termed manoeuvre warfare and its history, successes, and applications within a business context. Recounts some well‐known military and business decision making blunders and warns of the strategic implications of falling into the same flawed decision‐making traps. Concludes with arguments supporting aggressive strategies that exploit the elements of speed, surprise, and flexibility.

The purpose of this paper is to present an on-orbit frequency identification method for spacecraft directly using attitude maneuver data. Natural frequency of flexible solar arrays plays an important role in attitude control design of spacecraft with solar arrays, and its precision will directly affect the accuracy of attitude maneuver. However, when the flexibility of the solar arrays is large, because of air damping, gravity effect etc., the frequency obtained by ground test shows great error compared with the on-orbit real value. One solution to this problem is to conduct on-orbit identification during which proper identification methods are used to obtain the parameters of interest based on the real on-orbit data of spacecraft.

The observer/Kalman filter identification and eigensystem realization algorithm are used as identification methods, and the attitude maneuver controller is designed using the rigid-body dynamics method.

Two conclusions are drawn in this paper according to results of numerical simulations. The first one is that the attitude controller based on the rigid-body dynamics method is effective in attitude maneuver of the spacecraft. The second one is that the on-orbit parameter identification can be directly achieved by using attitude maneuver data of spacecraft without adding additional missions.

Based on the methods proposed in this paper, it is convenient to obtain the natural frequencies of the spacecraft using the data of the attitude maneuver, which may greatly reduce the cost of on-orbit identification test.

The way of obtaining natural frequencies based on attitude maneuver data of spacecraft provides high originality and value for practical application.

To provide a progress report into research conducted to establish guidelines for the development of guidance vision aids.

The first stage of the research is to establish a coherent engineering basis for the methods of (visual) motion perception and control to inform the design of pilot aids that will support flight in degraded visual conditions, particularly when close to the ground. The next stage will then be to construct and evaluate synthetic displays that recover the visual cues necessary to allow flight in degraded visual conditions for a range of manoeuvres using the flight simulation facilities at the University of Liverpool (UoL). The research is guided by tau (time to contact) theory from the field of ecological psychology.

The closure of spatial gaps for a number of aircraft manoeuvres are presented in the tau domain. Analysis of the landing flare manoeuvre suggest that both a constant rate of change of tau strategy and an intrinsic tau‐guidance strategy will yield benefits in terms of touchdown descent rate if presented as display symbology.

Results are presented from trials where only one professional pilot was used. Results from a wider population of pilots need to be analysed to ensure that the observed trends are generic.

The reported results are being used in the next phase of the research project to inform the design of a guidance vision‐aid for the flare manoeuvre. These displays will be tested in flight simulation trials.

The research takes a theory of motion perception and applies it to aircraft guidance display technology.