Attitude Tracking Problem Of Spacecraft Research Articles

Predefined-time attitude tracking control for uncertain rigid spacecraft with guaranteed performance

This brief tackles the predefined-time guaranteed performance attitude tracking problem of rigid spacecraft in presence of uncertain inertia and disturbances. Primarily, a novel non-singular predefined-time terminal sliding mode (NPTSM) surface with the prescribed performance attitude tracking errors is constructed. Secondly, a robust NPTSM control (NPTSMC) is developed to tackle the predefined-time attitude tracking problem for uncertain spacecraft. It is proved that the designed NPTSMC can assure that the attitude tracking errors satisfy the prescribed performance boundaries and globally converge to a predefined small region centered on the equilibrium point in predefined time and then converge to the equilibrium point asymptotically. The advantage of the NPTSMC is predefined-time stability with quantified transient, steady-state and settling time performance. The effectiveness performance of the exploited approach is verified numerical simulation results.

High-Performance Adaptive Attitude Control of Spacecraft With Sliding Mode Disturbance Observer

A new disturbance observer-based control method is presented in this paper to address the attitude tracking problem of rigid-body spacecraft in the presence of external disturbances and parameter uncertainties. Particularly, a sliding mode disturbance observer (SMDO) is designed. The most important feature of this SMDO is the relaxation of the assumption that external disturbances must be constants or changing at a slow rate, which is a typical assumption required in these classes of problems concerning disturbance observer (DO) design but hard to guarantee from the standpoint of practical engineering. In addition, a special adaptive integral sliding mode controller is combined with the SMDO to ensure system state convergence. The proposed control scheme’s primary advantage is the enhanced robustness against system parameter uncertainties and external disturbances. Stringent closed-loop system stability analysis is performed using Lyapunov-based stability theory. Numerical simulations are carried out on nonlinear model of spacecraft to validate the proposed control scheme’s efficiency compared to the existing methods in the literature.

Adaptive Fault-Tolerant Control for Attitude Tracking of Flexible Spacecraft With Limited Data Transmission

This article investigates the fault-tolerant control for attitude tracking problem of flexible spacecraft in the presence of actuator degradation, external disturbance, and signal quantization, where a logarithmic encoder-decoder scheme is employed for input quantization. A quantized adaptive terminal sliding mode control law is proposed to solve the attitude tracking problem. In this design, the quantizer parameters are injected to the controller gains to reject quantization errors, and the designed controller can compensate the effects of the unknown information, including actuator efficiency factors, external disturbance, and bounds of rigid-flexible coupled nonlinearity. It is shown that the attitude of the spacecraft can track the desired objective under the developed attitude controller. Finally, a simulation example is provided to verify the validness of the proposed attitude tracking control law.

Attitude tracking control for observation spacecraft flying around the target spacecraft

This paper addresses the attitude tracking problem of observation spacecraft, which is traveling around the target spacecraft. To observe the target spacecraft completely, view planning technology is used to select the optimal viewpoints where the observation spacecraft need to achieve and scans the target spacecraft. The desired attitude and desired angular velocity are determined by the relative location and relative velocity of the observation spacecraft with respect to the target spacecraft. The attitude tracking model are globally and uniquely described in the space of SO ( 3 ) × R 3 . Based on the sliding mode method, a nonlinear feedback controller is designed to track the desired attitude and desired angular velocity. The convergence and stability of the closed-loop system are assured by Morse-Lyapunov theorem and LaSalle's theorem. Moreover, it is proved that the attitude error and angular velocity error converge to a tolerable error interval regardless of actuator misalignment, uncertainties of the inertia matrix and external disturbed torque. In addition, the convergence interval is determined by the parameter setting in the controller. Finally, numerical simulations are presented to illustrate the effectiveness of the proposed controller.

ADAPTIVE SLIDING MODE ADRC FOR ATTITUDE TRACKING WITH ACTUATOR SATURATION AND UNCERTAINTIES

An adaptive sliding mode control (SMC) based on the active distur-bance rejection control (ADRC) scheme is put forward for spacecraftattitude tracking problems, in which there exist saturations, un-certainties, and disturbances.

Observer-Based Fault-Tolerant Spacecraft Attitude Tracking Using Sequential Lyapunov Analyses

The spacecraft attitude tracking problem is addressed with actuator faults and uncertainties among inertias, external disturbances, and, in particular, state estimates. A continuous sliding-mode attitude controller is designed using attitude and angular velocity estimates from an arbitrary stable stand-alone observer. Rigorous analysis shows that the controller ensures robust stability of the entire closed-loop system as long as the observer yields state estimates with uniformly ultimately bounded estimation errors. In addition, a sequential Lyapunov analysis is utilized to obtain a convergent sequence of analytical successively tighter upper bounds on the steady-state tracking error. Therefore, our results can be used to predict steady-state performance bounds given selected gains or facilitate gain selection given steady-state performance bounds. Numerical examples demonstrate the utility of the proposed theory.

Neural adaptive integral sliding mode control for attitude tracking of flexible spacecraft with signal quantisation and actuator nonlinearity

This study investigates the neural adaptive integral sliding mode control for attitude tracking of flexible spacecraft, where unknown actuator nonlinearity, input quantisation and external disturbances are considered simultaneously. In this design, the hysteresis encoder–decoder scheme is employed between the controller and actuator side for signal quantisation. A quantised adaptive integral sliding mode control strategy is developed, where the neural network scheme is applied to approximate the unmeasurable rigid-flexible coupled nonlinear dynamics. The proposed control strategy can compensate for quantisation error, actuator faults, actuator dead-zone as well as external disturbances effectively, and guarantee the trajectory of the attitude tracking error converge to the equilibrium point along the designed sliding surface. Finally, a simulation example is conducted to demonstrate the validness of the developed quantised control strategy for flexible spacecraft attitude tracking problem.

Attitude control of rigid spacecraft with predefined-time stability

This paper investigates the attitude tracking problem of a rigid spacecraft using contemporary predefined-time stability theory. To this end, the relative attitude kinematic and dynamic models of a spacecraft are presented. Then, a sliding mode surface and predefined-time stability theory are applied to ensure that both the tracking errors of the attitude, expressed by the quaternion and the angular velocity, converge to zero within a prescribed time. Simulation results demonstrate the performance of the proposed scheme.

Exponential and Resilient Control for Attitude Tracking Maneuvering of Spacecraft With Actuator Uncertainties

The spacecraft attitude tracking problem with exponential convergence and resilient control capability ensured is investigated. The system uncertainties induced by uncertain inertia and external disturbance, and the actuator uncertainties consisting of misalignment and faults, are addressed simultaneously. An observer-based exponential and resilient control scheme is presented. The closed-loop system is ensured to be stable that the attitude and the angular velocity tracking errors converge with an exponential rate to a small set with an arbitrary radius. The fast and high accuracy attitude tracking maneuver is accomplished. This resilient controller, characterized by a simple structure and less onboard computation, has great practical application potential. A rigid spacecraft example is shown to verify the effectiveness of the resilient solution with simulation and experimental results presented.

Fixed-Time Fault-Tolerant Attitude Tracking Control for Rigid Spacecraft

Abstract This paper addresses the fixed-time attitude tracking problem of rigid spacecraft with inertial uncertainties, external disturbances, and partial loss of actuator effectiveness faults. A new fixed-time terminal sliding surface is proposed and a singularity-free fixed-time fault-tolerant sliding mode control (FTSMC) is designed. It is proved that the proposed FTSMC can ensure that the attitude tracking errors converge to an arbitrary small bound centered on the equilibrium point within fixed time and then go to the equilibrium point asymptotically. The appealing features of the proposed control are fixed-time tracking stability featuring fast convergence, high precision, and strong robustness. Simulations verify the effectiveness of the proposed approach.

Multi-objective integrated robust H∞ control for attitude tracking of a flexible spacecraft

This paper investigates the multi-objective attitude tracking problem of a flexible spacecraft in the presence of disturbances, parameter uncertainties and imprecise collocation of sensors and actuators. An integrated robust H∞ controller, including an output feedback component and a feedforward component, is proposed, and its gains are calculated by solving Linear Matrix Inequalities. The output feedback component stabilizes the integrated control system while the feedforward component can drive the attitude motion to track the desired angles. The system robustness against disturbances, parameter uncertainties and imprecise collocation is addressed by the H∞ approach and convex optimization. Numerical simulations are finally provided to assess the performance of the proposed controller.

Convex Optimization for Power Tracking of Double-Gimbal Variable-Speed Control Moment Gyroscopes

This Paper addresses an integrated power/attitude control system for a spacecraft with two double-gimbal variable-speed control moment gyroscopes. Double-gimbal variable-speed control moment gyroscopes are of interest because a single device is a three-degree-of-freedom attitude actuator. A double-gimbal variable-speed control moment gyroscope has two gimbal axes and one variable-speed wheel. A primary advantage of adopting this actuator is to reduce the number of actuators, which leads to reducing the total mass and volume allocation within the spacecraft. In this Paper, first, the dynamical equations of motion of a spacecraft equipped with multiple double-gimbal variable-speed control moment gyroscopes are developed. Then, two types of steering laws are proposed for two double-gimbal variable-speed control moment gyroscopes. These steering laws attain three-axis attitude control and power tracking by using the wheels as energy storage devices while considering both singularity avoidance and wheel spin equalization. The controller design applies multiobjective gain scheduling with linear parameter-varying control theory, which can evaluate both optimality and robustness. Finally, numerical simulation examples of the orbiting spacecraft attitude tracking problem demonstrate the effectiveness of the proposed gain-scheduling controller and two steering laws for the integrated power/attitude control system.

Finite time control strategy for satellite attitude maneuver based on hybrid actuator

In this paper, a Nonsingular Terminal Sliding Mode Control (NTSMC) strategy is investigated to address the finite-time attitude tracking problem of a rigid spacecraft. Hybrid thruster and flywheel actuator system is used for rapid reorientation under external disturbance. The reference torque is obtained from time-optimal attitude trajectory, and it is exerted on the satellite by thrusters in the form of feedforward compensation. Owing to thruster output torque deviation, initial measurement error and external disturbances, the practical trajectory of a satellite would deviate from reference trajectory. In order for the satellite to track the reference trajectory in finite time, the correction torque is deduced based on the error between reference trajectory and real-time measurements, and then applied through flywheels in the form of feedback compensation. The NTSMC method is used to solve nonsingular problem and to improve the control precision of the satellite attitude tracking issue. The numerical simulation results show that this control strategy is effective and it has great robustness.

Robust spacecraft attitude tracking control using hybrid actuators with uncertainties

The problem of spacecraft attitude tracking using hybrid actuators with uncertainties is addressed in this paper. A hybrid actuators configuration that combines reaction wheels for fine pointing and single gimbal control moment gyros for rapid maneuvering is employed for agile spacecraft. A robust control algorithm for the spacecraft attitude tracking problem when the torque axis direction and/or input scaling of the actuators are uncertain is developed. Furthermore, a torque allocation method is proposed for the hybrid actuator configuration to allow a smooth switch between single gimbal control moment gyros and reaction wheels. With this method, single gimbal control moment gyros are used for the phase of rapid maneuvering, while reaction wheels are used for the phase of fine pointing. Simulation results demonstrate the effectiveness of the proposed control scheme.

Robust approach for attitude tracking and nonlinear disturbance rejection of rigid body spacecraft

This paper studies the attitude tracking and nonlinear external disturbances rejection problem of rigid body spacecraft by a robust state feedback control law motivated by nonlinear internal model design. This control law, independent of inertia matrix, can not only achieve asymptotic tracking of the desired attitude, but also reject nonlinear external disturbances in the control torque, generated by a so-called nonlinear exosystem. It is also worth mentioning that our control law is a much simpler and smooth one, which can beat the inherent drawback of a discontinuous one that might result in undesired chattering effect in the real applications. With the introduction of nonlinear internal model, we convert the attitude tracking and disturbance rejection problem of spacecraft to the global robust stabilisation problem of a complicated nonlinear multi-input, multi-output augmented system, and then perform a rigorous and sophisticated stability analysis of such nonlinear augmented system. Simulation results will also be provided to demonstrate the effectiveness of our design.

Finite‐Time Sliding Mode Trajectory Tracking Control of Uncertain Mechanical Systems

AbstractThe problem of finite‐time tracking control is studied for uncertain nonlinear mechanical systems. To achieve finite‐time convergence of tracking errors, a simple linear sliding surface based on polynomial reference trajectory is proposed to enable the trajectory tracking errors to converge to zero in a finite time, which is assigned arbitrarily in advance. The sliding mode control technique is employed in the development of the finite‐time controller to guarantee the excellent robustness of the closed‐loop system. The proposed sliding mode scheme eliminates the reaching phase problem, so that the closed‐loop system always holds the invariance property to parametric uncertainties and external disturbances. Lyapunov stability analysis is performed to show the global finite‐time convergence of the tracking errors. A numerical example of a rigid spacecraft attitude tracking problem demonstrates the effectiveness of the proposed controller.

Robust attitude tracking control scheme for a multi-body spacecraft using a radial basis function network and terminal sliding mode

We present a novel robust control scheme that deals with multi-body spacecraft attitude tracking problems. The control scheme consists of a radial basis function network (RBFN) and a robust controller. By using the finite time convergence property of the terminal sliding mode (TSM), we derive a new online learning algorithm for updating all the parameters of the RBFN that ensures the RBFN has fast approximation for the parameter uncertainties and external disturbances. We design a robust controller to compensate RBFN approximation errors and realise the anticipative stability and performance properties. We can also achieve closed-loop system stability using Lyapunov stability theory.No detailed knowledge of the non-linear dynamics of the spacecraft is required at any point in the entire design process, and the proposed robust scheme is simple and effective and can be applied to more complex systems. Simulation results demonstrate the good tracking characteristics of the proposed control scheme in the presence of inertial uncertainties and external disturbances.

Chattering-Free Adaptive Sliding Mode Control for Attitude Tracking of Spacecraft with External Disturbance

The attitude tracking problem of spacecraft in the presence of unknown disturbance is investigated. By using the adaptive control technique and the Lyapunov stability theory, a chattering-free adaptive sliding mode control law is proposed for the attitude tracking problem of spacecraft with unknown disturbance. Simulation results are employed to demonstrate the effectiveness of the proposed control design technique in this paper.

Attitude Tracking Control of Rigid Spacecraft With Actuator Misalignment and Fault

A control scheme is developed to address the attitude tracking problem of a rigid spacecraft. A sufficient condition to accommodate actuator misalignment is presented. The controller asymptotically stabilizes the closed-loop attitude tracking system. The desired attitude trajectories can be tracked in finite time, even in the presence of uncertain inertia tensor, external disturbances, actuator fault, and actuator misalignment. The attitude tracking performance of the controller is evaluated through an illustrative example.

Distributed adaptive attitude tracking of multiple spacecraft with a leader of nonzero input

This paper considers the distributed attitude tracking problem of multiple spacecraft with a leader whose control input is possibly nonzero, bounded, and not available to any follower. Based on the relative attitudes and angular velocities of neighboring spacecraft, we design a distributed discontinuous adaptive controller to each follower to guarantee that the attitude errors between the followers and the leader converge to zero for any communication graph containing a directed spanning tree with the leader as the root. To tackle the chattering effect caused by the discontinuous controller, we further propose a distributed continuous adaptive controller, under which both the attitude tracking errors and the adaptive gains are ultimately bounded.