Space subsystems design: (navigation, control, structure and…)
Valiollah Shahbahrami; Milad َAzimi; َAlireza Alikhani
Volume 16, Issue 4 , December 2023, , Pages 1-13
Abstract
In this paper, a robust adaptive hybrid control approach based on a combination of super-twisting and non-singular terminal sliding mode control (STNSMC) approaches for vibration and attitude control of a flexible spacecraft with fully coupled dynamic is developed. The proposed adaptation law eliminates ...
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In this paper, a robust adaptive hybrid control approach based on a combination of super-twisting and non-singular terminal sliding mode control (STNSMC) approaches for vibration and attitude control of a flexible spacecraft with fully coupled dynamic is developed. The proposed adaptation law eliminates the need for bounds knowledge of external disturbances and uncertainties. Then an ST-based NSMC generates a continuous control signal to reject the Chattering phenomenon, the non-singular terminal switching control law with the ability to generate continuous control commands to eliminate the chattering phenomenon. Moreover, finite-time convergence is achieved, and the singularity problem has been avoided. The overall stability of the system has been demonstrated using the Lyapunov theory. One of the essential features of the proposed control algorithm is to prevent overestimation of control gains and faster convergence rates comparing to conventional ST and non-singular terminal SMC approaches. The simulations in the form of a comparative study for large-angle maneuver reveal the advantage of the proposed approach.
Reza Yavari; Iman Mohammadzaman; Mohammad Reza Arvan
Volume 9, Issue 4 , April 2017, , Pages 39-50
Abstract
In this paper, a novel integrated guidance and control (IGC) approach is designed using the combination of backstepping and sliding mode control methods. In contrast to the traditional methods combining the kinematic and dynamic equations and deriving a state space model as an integrated unit model, ...
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In this paper, a novel integrated guidance and control (IGC) approach is designed using the combination of backstepping and sliding mode control methods. In contrast to the traditional methods combining the kinematic and dynamic equations and deriving a state space model as an integrated unit model, the proposed method designs the guidance and control problem in a single loop. This algorithm is robust with respect to the uncertainties in the target acceleration and missile dynamic model. Simulation results using six-degrees-of-freedom simulation aerodynamic model (6DOF) and three-dimension (3-D) engagement show that the proposed IGC design, with guidance and control dynamic synergism, eventuates interception with the maneuvering target.
Vahid Behnamgol; Ahmad Reza Vali; Ali Mohammadi
Volume 8, Issue 4 , January 2016, , Pages 9-17
Abstract
In this paper, a new procedure for designing the guidance law considering the control loop dynamics is proposed. The nonlinear guidance loop entailing a first order lag as the control loop dynamics is formulated. A new finite time and smooth backstepping sliding mode control scheme is used to guarantee ...
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In this paper, a new procedure for designing the guidance law considering the control loop dynamics is proposed. The nonlinear guidance loop entailing a first order lag as the control loop dynamics is formulated. A new finite time and smooth backstepping sliding mode control scheme is used to guarantee the finite time convergence of relative lateral velocity. Also in the proposed algorithm the chattering is removed and a smooth control signal is produced. Moreover, the target maneuver is considered as an unmatched uncertainty. Then a robust guidance law is designed without requiring the precise measurement or estimation of target acceleration. Simulation results show that the proposed algorithm has better performance as compared to the proportional navigation, augmented PN and the other sliding mode guidance law.
M. Sayanjali; J. Roshanian; A. Ghafari
Volume 2, Issue 1 , April 2009, , Pages 43-50
Abstract
In this paper, equation of motion of three axis attitude dynamic of flexible spacecraft is derived using combination of finite element method and Euler equation. Flexible appendafes are modeled by beam elements. Goal of control is target attitude of spacecraft from initial state to desired attitude and ...
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In this paper, equation of motion of three axis attitude dynamic of flexible spacecraft is derived using combination of finite element method and Euler equation. Flexible appendafes are modeled by beam elements. Goal of control is target attitude of spacecraft from initial state to desired attitude and suppression of vibration that induced in flexible appendages. So a combination of backstepping and sliding mode control method used for three-axis attitude maneuver of flexible spacecraft and for suppressing vibration of flexible appendage used from active vibration control method by PZT actuator. Control law for vibration control is based on LQG method
