Component Synthesis Vibration Suppression Method Research Articles

Flexible spacecraft attitude maneuver via adaptive sliding mode control and mixed component synthesis vibration suppression

<p indent=0mm>A mixed component synthesis vibration suppression method (MCSVS) is proposed to solve the problem of residual vibration of flexible attachments, which is difficult to control effectively. Theorems and inferences are provided, and their proofs are performed. Aiming at the problem that the attitude controllers cannot suppress the vibration of flexible attachments in spacecraft attitude maneuver, a strategy combining the MCSVS method with an attitude control method is proposed. Considering the existence of moment of inertia variation and external disturbance of spacecraft, an adaptive sliding mode variable structure controller is proposed. By introducing a sliding mode boundary layer and the update rate of the torque parameter, the disadvantages of torque chattering and parameter dependence are eliminated. Finally, the joint application of the MCSVS method and the adaptive variable structure controller is realized with the assistance of piezoelectric intelligent materials. Simulation results show that the control strategy without the MCSVS method cannot suppress the vibration of flexible attachments. After combining the MCSVS method with the attitude control method, the residual vibration is well controlled, and the attitude accuracy is improved.

Hybrid control of a satellite with membrane antenna considering nonlinear vibration

In this paper, the hybrid control of attitude maneuver and nonlinear vibration of a satellite with membrane antenna structure is studied. Considering the geometric nonlinearity of large-amplitude vibration, a nonlinear dynamic model of the membrane antenna structure is established, and then a reduced order nonlinear dynamic model is obtained by using the polynomial fitting method. Based on the hybrid coordinate method, the nonlinear rigid-flexible coupling dynamic model of the satellite with membrane antenna structure is built. An active control strategy which contains two subsystems (the attitude control subsystem and the nonlinear vibration suppression subsystem) is proposed to control the attitude maneuver and nonlinear vibration simultaneously. In the attitude control subsystem, component synthesis vibration suppression method combined with pulse width modulator is utilized to reduce the vibration of the membrane antenna structure during attitude maneuvers. And a nonlinear vibration suppression subsystem based the sliding mode control method is designed to suppress the nonlinear vibration further. Simulation results show that with these two subsystems working together, the nonlinear vibration of the membrane antenna structure can be suppressed effectively, and the accuracy of attitude maneuver of the satellite will be improved significantly.

Active vibration suppression for flexible satellites using a novel component synthesis method

This paper is devoted to developing a closed-loop vibration suppression controller for a satellite with large flexible appendages based on component synthesis vibration suppression (CSVS) method. The dynamics model of a flexible satellite is firstly established by using the Newton–Euler methodology, and the dynamics model of the flywheel is also developed. A novel CSVS method is presented based on zero-vibration differentiator (ZVD), which can guarantee multi-order vibration suppression. Combined with the proposed CSVS method, traditional closed-loop controllers such as PD or sliding mode controllers can be applied to active vibration suppression. The stability of the proposed closed-loop CSVS controller is proved by the Lyapunov theory. Subsequently, the dynamic optimal control allocation algorithm is proposed for six flywheels, and a novel nonsingular fast terminal sliding mode controller is developed to obtain practical voltage control input for the flywheel drive control system. Finally, numerical simulations are carried out to validate the effectiveness of the proposed method.

Flexible satellite control via fixed-time prescribed performance control and fully adaptive component synthesis vibration suppression

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.

CSVS Method for Spacecraft with Two Flexible Appendages during Attitude Maneuver

An angle maneuver control strategy of spacecraft with two flexible appendages based on component synthesis vibration suppression (CSVS) method is put forward. Unwanted flexible vibration modes can be eliminated while desired rigid motion can be achieved by this method. Jet device and Momentum wheel system are used as the actuator of the spacecraft’s angle maneuver. Several time-fuel control strategies are designed for spacecraft with flexible appendages. Simulation results validate the feasibility of the CSVS method. The DC motor control method is researched in order to combine momentum wheel system with CSVS method.

FLEXIBLE SPACECRAFT VIBRATION SUPPRESSION USING PWPF MODULATED INPUT COMPONENT COMMAND AND SLIDING MODE CONTROL

ABSTRACTThis paper presents a dual‐stage control system design method for the rotational maneuver and vibration stabilization of a spacecraft with flexible appendages. In this design approach, attitude control system and vibration suppression were designed separately using lower order model. The design of attitude controller was based on sliding mode control (SMC) theory leading to a discontinuous control law. This controller accomplishes asymptotic attitude maneuvering in the closed‐loop system and is insensitive to the interaction of elastic modes and uncertainty in the system. The shaped command input controller based on component synthesis vibration suppression (CSVS) method is designed for reduction of flexible mode vibration, which only requires information about natural frequency and damping of the closed system. Additionally, to extend the CSVS method to the system with on‐off actuators, pulse‐width pulse‐frequency (PWPF) modulation is employed to control the thruster firing and integrated with the CSVS method. Simulation results have been proven the potential of this technique to control flexible spacecraft.

FEED-FORWARD/FEEDBACK CONTROL FOR ACTIVE VIBRATION SUPPRESSION OF FLEXIBLE SPACECRAFT DURING ATTITUDE MANEUVER

This paper presents an investigation into development of feed-forward and feedback control strategies for active vibration suppression and attitude control of flexible spacecrafts. The feed-forward loop consists of a computed-torque scheme and a command shaping technique based on component synthesis vibration suppression (CSVS) method which was developed based on linear systems theory. For relaxing the requirements of dynamic linearity in traditional input component command in CSVS method, a new approach is developed for designing the input component command by utilizing a structure in which the modal forces of flexible modes vibration are shaped according to a predefined trajectory, which improves the performance of CSVS method in vibration suppression for the nonlinear attitude dynamics. This proposed control strategy is practical as it does not require direct measurement of flexible appendage vibration, and also has a simple structure with low on-line computational load. Numerical simulations demonstrate the effectiveness of the control strategy.