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This paper aims to present an attitude determination and control system for a nano‐astrometry satellite which requires precise angular rate control. Focus of the research is methods to achieve the requirement.

In order to obtain astrometry data, the satellite attitude should be controlled to an accuracy of 0.05°. Furthermore, attitude spin rate must be controlled to an accuracy of 4×10⁻⁷ rad/s during observation. In this paper the following unique ideas to achieve these requirements are introduced: magnetic disturbance compensation and rate estimation using star blurred images.

This paper presents the feasibility of a high accurate attitude control system in nano‐ and micro‐satellite missions.

This paper presents a possibility of the application of nano‐satellites to remote‐sensing and astronomy mission, which requires accurate attitude control.

Originalities of the paper are the methods to achieve the high accurate attitude control: magnetic disturbance compensation and angular rate estimation using star images.

This paper aims to investigate the attitude control pointing improvement for a small satellite with control moment gyroscopes (CMGs) using the active force control (AFC) method.

The AFC method is developed with its governing equations and integrated into the conventional proportional-derivative (PD) controller of a closed-loop satellite attitude control system. Two numerical simulations of an identical attitude control mission namely the PD controller and the PD+AFC controller were carried out using the MATLAB^®-SimulinkTM software and their attitude control performances were demonstrated accordingly.

Having the PD+AFC controller, the attitude maneuver can be completed within the desired slew rate, which is about 2.14 degree/s and the attitude pointing accuracies for the roll, pitch and yaw angles have improved significantly by more than 85% in comparison with the PD controller alone. Moreover, the implementation of the AFC into the conventional PD controller does not cause significant difference on the physical structure of the four single gimbal CMGs (4-SGCMGs).

To achieve a precise attitude pointing mission, the AFC method can be applied directly to the existing conventional PD attitude control system of a CMG-based satellite. In this case, the AFC is indeed the backbone for the satellite attitude performance improvement.

The present study demonstrates that the attitude pointing of a small satellite with CMGs is improved through the implementation of the AFC scheme into the PD controller.

The Pupil Control Ideology (PCI) concept has been used extensively to describe the school organization. Teachers hate been described as either “custodial” or “humanistic” in their belief orientation to control of pupils. But clarification of the nature of pupil control and the teacher attitudes which lie at the base of control, has not been investigated adequately. The first section of the present investigation indicates the attitudes of teachers which are associated with high levels of custodialism. These attitudes include emphasis on, content to be taught, teacher direction, rigid classroom procedures and social disengagement from pupils. The second part of the study shows that while operational measures of control may be similar, attitudes underlying control may differ. In schools serving higher socio‐economic communities, teachers exhibit an “emotional disengagement—non‐teacher direction” form of ideology. The conclusion is drawn that unless future investigations both identify attitudes and explain the interactions of attitudes of teachers in each school system, Pupil Control Ideology may be an inadequate descriptor of the school as a social system.

The satellite pointing accuracy plays a crucial role in ensuring a successful satellite mission itself. Therefore, this paper aims to enhance the attitude pointing accuracy of the combined energy and attitude control system (CEACS) in a satellite in the presence of external disturbance torques through a robust controller, which can produce high pointing accuracies with smaller control torques.

To improve the CEACS attitude pointing accuracy, a maiden fuzzy proportional derivative (PD)-based CEACS architecture is proposed. The mathematical models along with its numerical treatments of the fuzzy PD-based CEACS attitude control architecture are presented. In addition, a comparison between the PD and fuzzy PD controllers in terms of the CEACS pointing accuracies and control torques is provided.

Numerical results show that the fuzzy PD controller produces a considerable CEACS pointing accuracy improvement for a lower control torque compartment.

CEACS has gained a renew interest because of significant increase in the projected onboard power requirements for future space missions. Therefore, it is of paramount importance to improve the CEACS pointing accuracy itself with a minimum control torque compartment. In fact, this proposed fuzzy PD controller is shown to be a potential CEACS attitude controller.

The fuzzy PD-based CEACS architecture not only provides a better attitude pointing accuracy but also ensures a lower control torque compartment, which corresponds to a lower onboard power consumption.

This paper aims to investigate the fast attitude coordinated control problem for rigid satellite swarms with communication delays.

Based on behavior‐based control approach, the attitude control system is designed to guarantee that the attitude of the satellite swarm converge to a dynamic reference state in finite time. A fast sliding mode is developed to improve the convergence rate and robustness of the control system. All the effects of communication delays, parameter uncertainties and external disturbances are taken into account simultaneously, and the communication topology of the satellite swarm can be arbitrary types. Numerical simulations are provided to demonstrate the analytic results.

Despite the existence of communication delays, parameter uncertainties and external disturbances, the stability of the closed‐loop system can be successfully guaranteed and the proposed control strategies are effective to overcome these unexpected phenomena subject to arbitrary communication topology.

This paper introduces a fast terminal sliding mode control method which can guarantee the fast convergence of the attitude state of the satellite swarm in the presence of communication delays, switched communication topology, parameter uncertainties and external disturbances.

This study aims to establish the laser links between satellites among large-scale distributed satellite systems; a combined attitude control strategy containing two stages is proposed in this paper.

These two stages are: one is the attitude initial pointing control to change the attitude of satellite pointing to the other satellite based on the position information of each satellite; the other one is the high precision attitude tracking control to scan the uncertainty cone because the initial pointing control accuracy is not enough to establish the laser link. At the initial pointing control stage, a method to determine the target attitude of each satellite is presented based on the position information of each satellite, and the fuzzy adaptive control algorithm is used to control the satellites to its calculated attitude. Then, at the high precision attitude tracking control stage, a strategy for laser link acquisition and scanning the uncertainty cone by the lasers of the spacecraft is proposed, and an angular velocity tracking scanning controller is designed while the convergence of the attitude tracking error is ensured through Lyapunov–Krasovskii theory.

Simulations are conducted to verify the effectiveness of the proposed control algorithm, and the laser link for a large-scale distributed satellite system with super long distance is achieved through a combined attitude control strategy.

A combined attitude control strategy is valid for a large-scale distributed satellite system with super long distance.

A combined attitude control strategy can be used to achieve laser link acquisition for a large-scale distributed satellite system like space gravitational wave detection.

A combined attitude control strategy can provide a way to solve the typical problem that pointing control accuracy is not enough to establish the laser link for a large-scale distributed satellite system.

The study examines superintendents' attitudes toward community participation at the advisory and control levels in four areas of educational policy making: curriculum, student policy, finances, and personnel. Three hypotheses were posed: (1) superintendents' attitudes toward community advisement would be more favourable than their attitudes toward community control; (2) attitudes would differ on four selected school issues; (3) five independent variables (size, ethnic composition of system geographic location, geographic setting, and type of community involvement practiced) would influence the superintendents' attitudes toward advice and control. The names of superintendents with student populations over 15,000 were obtained from the Educational Directory. Superintendents' attitudes toward community participation at the advisory and control levels were measured on the Community Participation—Community Control Attitudinal Inventory. The results support hypotheses (1) and (2). For hypothesis (3), only size (over 50,000/under 50,000) and school setting (suburban/city) were significant independent variables. The larger the system the more favourable the superintendents' attitudes toward community advisement on curriculum issues, student policy issues, and personnel issues. However, they held less favourable attitudes toward community control of school finances than superintendents from smaller school districts. On community advisement re student policy issues, superintendents from city school districts held more favourable attitudes than their suburban counterparts; they held, however, less favourable attitudes on community control of school finance issues than suburban superintendents.

This paper aims to present an intelligent motion attitude control algorithm, which is used to solve the poor precision problems of motion-manipulation control and the problems of motion balance of humanoid robots. Aiming at the problems of a few physical training samples and low efficiency, this paper proposes an offline pre-training of the attitude controller using the identification model as a priori knowledge of online training in the real physical environment.

The deep reinforcement learning (DRL) of continuous motion and continuous state space is applied to motion attitude control of humanoid robots and the robot motion intelligent attitude controller is constructed. Combined with the stability analysis of the training process and control process, the stability constraints of the training process and control process are established and the correctness of the constraints is demonstrated in the experiment.

Comparing with the proportion integration differentiation (PID) controller, PID + MPC controller and MPC + DOB controller in the humanoid robots environment transition walking experiment, the standard deviation of the tracking error of robots’ upper body pitch attitude trajectory under the control of the intelligent attitude controller is reduced by 60.37 per cent, 44.17 per cent and 26.58 per cent.

Using an intelligent motion attitude control algorithm to deal with the strong coupling nonlinear problem in biped robots walking can simplify the control process. The offline pre-training of the attitude controller using the identification model as a priori knowledge of online training in the real physical environment makes up the problems of a few physical training samples and low efficiency. The result of using the theory described in this paper shows the performance of the motion-manipulation control precision and motion balance of humanoid robots and provides some inspiration for the application of using DRL in biped robots walking attitude control.

The purpose of this paper is to develop a theoretical design for the alternative attitude control of the rotation about the pitch axis for the nadir-pointing spacecraft in the event of inertial actuator faults.

This paper presents a novel and viable solution to that problem using the combined attitude and sun tracking system (CASTS) that was conceived from an engineering problem-solving toolkit called TRIZ. Linear and fuzzy controllers are used to test the spacecraft CASTS architecture. All the relevant governing equations of the control system and disturbance rejection methods are developed.

The performance of the proposed CASTS control strategy is tested through numerical simulations. The results strongly suggest that the novel proposed control scheme is effective and promising for controlling the satellite attitude and sun tracking simultaneously in the presence of disturbance torques.

This work is mainly focused on the rigid body of the spacecraft hub that contains all attitude control hardware and payload instrumentation, and does not deal with the vibrations evolving from the propellant sloshing and large flexible appendages such as the deployable solar panels and synthetic aperture radar antennas.

The results from this work reveal several practical applications worthy of reducing the weight, size of the spacecraft and, therefore, cost of missions while increasing the instrumentation capabilities.

The proposed CASTS solution is a result of looking much wider than one system from a new combination of attitude control and sun tracking, as well as innovative ways of using it.

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.