Explore the vast range of titles available.

In this paper, a novel adaptive fuzzy proportional–integral–derivative (AFPID) controller is designed for geostationary satellite attitude control. In order to design the AFPID controller, first a fuzzy PID (FPID) controller is proposed in which two fuzzy inference engines are used: single-input fuzzy inference engine (SIFIE) and preferential fuzzy inference engine (PFIE). SIFIE has only one input which means a separate SIFIE is assigned to each state variable, and on the other side, PFIE represents the control priority order of each state variable. Consequently, control gains of FPID controller will be adjusted and updated with a sliding mode-based adaptation mechanism. As a result, via numerical simulations, objectives of the AFPID controller in terms of faster convergence time and higher performance are achieved.

With the continuous proliferation of satellites, accurately determining their operational status is crucial for satellite design and on-orbit anomaly detection. However, existing research overlooks this crucial aspect, falling short in its analysis. Through an analysis of real-time satellite telemetry data, this paper pioneers the introduction of four distinct operational states within satellite attitude control systems and explores the challenges associated with their classification and prediction. Considering skewed data and dimensionality, we propose the Two-Step Graph Convolutional Neural Network (TS-GCN) framework, integrating resampling and a streamlined architecture as the benchmark of the proposed problem. Applying TS-GCN to a specific satellite model yields 98.93% state recognition and 99.13% prediction accuracy. Compared to the Standard GCN, Standard CNN, and ResNet-18, the state recognition accuracy increased by 37.36–75.65%. With fewer parameters, TS-GCN suits on-orbit deployment, enhancing assessment and anomaly detection.

A satellite can only complete its mission successfully when all its subsystems, including the attitude control subsystem, are in healthy condition and work properly. Control moment gyroscope is a type of actuator used in the attitude control subsystems of satellites. Any fault in the control moment gyroscope can cause the satellite mission failure if it is not detected, isolated, and resolved in time. Fault diagnosis provides an opportunity to detect and isolate the occurring faults and, if accompanied by proactive remedial actions, it can avoid failure and improve the satellite reliability. In this paper, an enhanced data-driven fault diagnosis is introduced for fault isolation of multiple in-phase faults of satellite control moment gyroscopes that has not been addressed in the literature before with high accuracy. The proposed method is based on an optimized support vector machine, and the results yield fault predictions with up to 95.6% accuracy. In addition, a sensitivity analysis with regard to noise, missing values, and missing sensors is done. The results show that the proposed model is robust enough to be used in real applications.

The reaction flywheel is a crucial operational component within a satellite’s attitude control system. Enhancing the performance of the reaction flywheel speed control system holds significant importance for satellite attitude control. In this paper, an active disturbance rejection control (ADRC) approach is introduced to mitigate the impact of uncertain disturbances on reaction flywheel speed control precision. The reaction flywheel speed control system is designed as an ADRC controller due to the current challenge of measuring unknown disturbances accurately in the reaction flywheel system. To derive the rotor’s speed observation value and the estimated total disturbances value, the sampled data of the reaction flywheel rotor position and torque control signal are fed into the extended state observer. The estimated total disturbances value is compensated on feedforward control, which could mitigate significantly the effects of various nonlinear disturbances. The paper initially establishes the rationale behind the reaction flywheel ADRC controller through theoretical analysis, followed by analysis of the differences of performance of reaction flywheel control by the ADRC controller and the PID controller in MATLAB/SIMULINK. Simulation results demonstrate the evident advantages of the ADRC controller over the PID controller in terms of speed command tracking capability and disturbances suppression ability. Subsequently, the ADRC controller program and the PID controller program are implemented on the reaction flywheel control circuit, and experiments are conducted to contrast speed command tracking and disturbance suppression. Importantly, the experimental outcomes align with the simulation results.

Purpose This paper aims to describe a novel type of attitude control system (ACS) in different configurations. This servomechanism is compared with control moment gyro (CMG) in significant parameters of performance for ACS of rigid satellite. Design/methodology/approach This new actuator is the fluid containing one or more rings and fluid flow is supplied by pump. The required torque control is obtained by managing fluid angular velocity. The cube-shaped satellite with three rings of fluid in the principle axes is considered for modeling. The satellite is considered rigid and nonlinear dynamics equation is used for it. In addition, the failure of the pyramid-shaped satellite with an additional ring fluid is discussed. Findings The controller model for four fluid rings has more complexity than for three fluid rings. The simulation results illustrated that four fluid rings need less energy for stabilization than three fluid rings. The performance of this type of actuator is compared with CMG. At last, it is demonstrated that performance parameters are improved with fluid ring actuator. Research limitations/implications Fluid ring actuator can be affected by environmental pressure and temperature. Therefore, freezing and boiling temperature of the fluid should be considered in system designation. Practical implications Fluid ring servomechanism can be used as ACS in rigid satellites. This actuator is compared by CMG, the prevalent actuator. It has less displacement attitude maneuver. Originality/value The results provide the feasibility and advantages of using fluid rings as satellite ACS. The quaternion error controller is used for this model to enhance its performance.

This paper addresses the multi-constraint attitude control problem for micro-satellites. A highly integrated energy-attitude model is developed, overcoming the limitations of traditional modular disciplinary designs. The model enables collaborative optimization of energy constraints and communication link constraints, achieving a 98% reduction in computation time while maximizing link duration. This significantly enhances computational efficiency and result stability. Validation cases demonstrate that the model effectively captures the coupling relationships among attitude control, energy management, and communication link disciplines, contributing to improved mission execution efficiency and scientific mission planning. The study also identifies existing limitations in the number of coupled disciplines and autonomy of planning methods, outlining future work to expand the coupled disciplines and increase model applicability.

The next-generation satellite navigation system proposes establishing a connection between the inertial frame and the Earth-Fixed Frame (ECF) based on spaceborne observation methods to achieve long-term autonomous operation. The star-tracking camera simultaneously images both stars and the target navigation satellite, enabling high-precision measurements of the inertial observation vector between the observing satellite and the target satellite. This capability serves as a crucial measurement means for precisely fixing the satellite constellation to the celestial reference frame. This paper systematically reviews the two main types of optical acquisition techniques for navigation satellites based on the differing characteristics of optical signal emission. Active beacon light acquisition achieves sub-pixel level positioning through controllable emission of modulated light beams, effectively supporting high-precision attitude control tasks such as rapid alignment of inter-satellite laser communication terminals. In contrast, passive reflected light acquisition utilizes the diffuse reflection of solar radiation from satellite surfaces to enable inter-satellite identification and orbit prediction under passive conditions, making it suitable for missions such as close-range docking and autonomous navigation. By comparing the fundamental principles, implementation approaches, and applicable scenarios of these two techniques, the paper analyzes and evaluates various methods and algorithms. Finally, it summarizes both approaches and provides an outlook on future research trends in the field of navigation satellite acquisition.

In this work, the problems of active vibration suppression and high accuracy attitude control for a flexible satellite with piezoelectric actuators are studied. Firstly, the attitude error dynamic equation is developed. By utilizing a novel hyperbolic cosecant function and the error transformation equation, the attitude errors can be transferred into new prescribed performance state variables. In order to further ensure better convergence of the new variables, a fixed-time sliding mode control is proposed. Subsequently, a novel fully adaptive component synthesis vibration suppression method is presented to realize vibration suppression during the attitude maneuver by utilizing piezoelectric actuators. Stability analysis of the proposed prescribed performance control is given. Finally, abundant numerical simulation results demonstrate the excellent performances of the proposed control scheme.

The star sensor is a crucial instrument for realizing the attitude measurement of satellites and the control of aircraft. Its detection accuracy directly influences the attitude control performance of space platforms such as satellites and aircraft. Aiming at the problem of significant differences in the detection capabilities of star sensors in different batches at present, this paper proposes a consistency constraint method for the detection capability of star sensors based on the image quality characteristics of star point detection. This method establishes a star point image evaluation model that includes the Gray_mean, Star_size, Gray_concent, and Gray_balance, constructs a complete parameter constraint system, and realizes the quantitative evaluation and optimized control of the imaging quality of star points at different positions on the detector phase plane during optical alignment. The experiment was verified based on multiple batches of products of a certain type of star sensor. The results show that this method can stably control the detection capabilities of star sensors in different batches within ±20%, significantly improving the stability of the detection performance during the mass production of star sensors. The research findings provide an effective approach to ensuring the consistency of the detection capabilities of star sensors in different batches and possess important engineering value for guaranteeing the on-orbit performance of the networking tasks of spacecraft.

This paper presents a novel robust attitude cooperation scheme that integrates an adaptive cooperative strategy with fractional-order PID for satellite formation systems subject to external disturbances. Firstly, the theoretical foundations for the attitude dynamics model of the considered satellites are derived. Secondly, to achieve attitude cooperation, a cross-coupled attitude cooperative error is designed, where adaptive weighting dynamically regulates cooperative performance among multiple satellites. Thirdly, a fractional-order PID controller is developed based on the adaptive cooperation strategy, which significantly reduces system chattering and improves the attitude cooperation between satellites while ensuring fast attitude convergence. Finally, numerical simulations validate the effectiveness of the presented controllers under disturbance scenarios.