A signed switching time bang-bang attitude control law for fine pointing of flexible spacecraft†

1984 ◽  
Vol 40 (4) ◽  
pp. 795-811 ◽  
Author(s):  
S. J. DODDS ◽  
S. E. WILLIAMSON
Keyword(s):  
Attitude Control ◽  
Switching Time ◽  
Flexible Spacecraft ◽  
Control Law

scholarly journals Adaptive Backstepping Attitude Control Law with L2-Gain Performance for Flexible Spacecraft

2019 ◽  
Vol 2019 ◽  
pp. 1-11
Author(s):  
Rui-Qi Dong ◽  
Yu-Yao Wu ◽  
Ying Zhang ◽  
Ai-Guo Wu
Keyword(s):  
Attitude Control ◽  
External Disturbance ◽  
Performance Criterion ◽  
Lyapunov Theory ◽  
Flexible Spacecraft ◽  
Control Law ◽  
Adaptive Backstepping ◽  
Unknown Parameters ◽  
Inertia Matrix ◽  
Attitude Maneuver

In this paper, an observer-based adaptive backstepping attitude maneuver controller (briefly, OBABC) for flexible spacecraft is presented. First, an observer is constructed to estimate the flexible modal variables. Based on the proposed observer, a backstepping control law is presented for the case where the inertia matrix is known. Further, an adaptive law is developed to estimate the unknown parameters of the inertia matrix of the flexible spacecraft. By utilizing Lyapunov theory, the proposed OBABC law can guarantee the asymptotical convergence of the closed-loop system in the presence of the external disturbance, incorporating with the L2-gain performance criterion constraint. Simulation results show that the attitude maneuver can be achieved by the proposed observer-based adaptive backstepping attitude control law.

Smooth time-optimal attitude control of spacecraft

2018 ◽  
Vol 233 (7) ◽  
pp. 2331-2343 ◽  
Author(s):  
Yabo Hu ◽  
Baolin Wu ◽  
Yunhai Geng ◽  
Yunhua Wu
Keyword(s):  
Attitude Control ◽  
Trajectory Optimization ◽  
Angular Acceleration ◽  
Optimization Method ◽  
Frequency Domain Analysis ◽  
Flexible Spacecraft ◽  
Control Law ◽  
Control Torque ◽  
Attitude Maneuver ◽  
Time Optimal

In this paper, a trajectory optimization method for generating smooth and approximate time-optimal attitude maneuver trajectories of flexible spacecraft is proposed. Smooth attitude maneuver is highly desirable for flexible spacecraft, since vibration of flexible appendices can be suppressed. In order to obtain smooth and approximate time-optimal attitude trajectory, a novel objective function composed of two terms is developed in the problem of trajectory optimization: the first term is proportional to the total maneuver time and the other one is proportional to the integral of the squared control torque derivatives. This latter term ensures that the generated trajectory is smooth. The degree of the smoothness of the trajectory can be adjusted by the weights of these two terms. The constraints on angular velocity and angular acceleration are considered in the proposed method. A closed-loop tracking control law is then employed to track the optimized reference attitude trajectory. Numerical simulations and frequency domain analysis show that the proposed method can generate smoother trajectory than traditional time-optimal methods, which leads to less vibration during attitude maneuver of a flexible spacecraft.

Active Control Comparison of Vibration in Flexible Spacecraft Using Different Active Friction Joints

2013 ◽  
Vol 446-447 ◽  
pp. 1160-1164
Author(s):  
Sahar Bakhtiari Mojaz ◽  
Hamed Kashani
Keyword(s):  
Energy Dissipation ◽  
Attitude Control ◽  
Vibration Suppression ◽  
Excitation Amplitude ◽  
Step Function ◽  
Flexible Spacecraft ◽  
Control Effort ◽  
Stick Slip ◽  
Control Comparison ◽  
Frictional Joints

Vibration properties of most assembled mechanical systems depend on frictional damping in joints. The nonlinear transfer behavior of the frictional interfaces often provides the dominant damping mechanism in structure and plays an important role in the vibratory response of it. For improving the performance of systems, many studies have been carried out to predict measure and enhance the energy dissipation of friction. This paper presents a new approach to vibration reduction of flexible spacecraft with enhancing the energy dissipation of frictional dampers. Spacecraft is modeled as a 3 degree of freedom mass-spring system which is controlled by a lead compensator and System responses to step function evaluated. Coulomb and Jenkins element has been used as vibration suppression mechanisms in joints and sensitivity of their performance to variations of spacecraft excitation amplitude and damper properties is analyzed. The relation between frictional force and displacement derived and used in optimization of control performance. Responses of system and control effort needed for the vibration control are compared for these two frictional joints. It is shown that attitude control effort reduces, significantly with coulomb dampers and response of system improves. On the other hand, due to stick-slip phenomena in Jenkins element, we couldn’t expect the same performance from Jenkins damper.

Comparison of a Fuzzy Logic Controller With a P + D Control Law

1989 ◽  
Vol 111 (2) ◽  
pp. 128-137 ◽  
Author(s):  
S. Daley ◽  
K. F. Gill
Keyword(s):  
Fuzzy Logic ◽  
Attitude Control ◽  
Fuzzy Logic Control ◽  
Fuzzy Logic Controller ◽  
Good Control ◽  
Control Law ◽  
Dynamic Coupling ◽  
Process Knowledge ◽  
Logic Control ◽  
Limited Process

A study is described that compares the performance of a self-organizing fuzzy logic control law (SOC) with that of the more traditional P + D algorithm. The multivariate problem used for the investigation is the attitude control of a flexible satellite that has significant dynamic coupling of the axes. It is demonstrated that the SOC can provide good control, requires limited process knowledge and compares favorably with the P + D algorithm.

scholarly journals Nonlinear Hybrid Controller for a Quadrotor Based on Sliding Mode and Backstepping

2015 ◽  
Vol 4 (3) ◽  
pp. 209
Author(s):  
Chuan Lian Zhang ◽  
Kil To Chong
Keyword(s):  
Attitude Control ◽  
Position Control ◽  
Sliding Mode ◽  
Lyapunov Theory ◽  
Control Law ◽  
Dynamics Modeling ◽  
Hybrid Controller ◽  
Navigation Simulation ◽  
Waypoint Navigation ◽  
Nonlinear Hybrid

<span>In this paper, one nonlinear hybrid controller, based on backstepping and sliding mode, was developed and applied to a quadrotor for waypoint navigation application. After dynamics modeling, the whole quadrotor dynamics system could be divided into two subsystems: rotational system and translational system. Backstepping control law was derived for attitude control whereas sliding mode control law was developed for position control. By using Lyapunov theory and satisfying sliding stable rules, the convergence of system could be guaranteed. A nonlinear equation was proposed to solve the under-actuated problem. To validate the effectiveness of proposed nonlinear hybrid controller, waypoint navigation simulation was performed on the nonlinear hybrid controller. Results showed that the nonlinear hybrid controller finished waypoint navigation successfully.</span>

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