Hamed Chenarani; Tahereh Binazadeh; Mohammad Hosein Shafiei
Volume 11, Issue 2 , September 2018, , Pages 41-46
Abstract
This paper considers the problem of asymptotic stabilizing of velocity and body rates of a spacecraft in the presence of uncertainties and external disturbances. One of the important methods in controller design for nonlinear systems; is designing based on the passivity concept. This concept which provides ...
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This paper considers the problem of asymptotic stabilizing of velocity and body rates of a spacecraft in the presence of uncertainties and external disturbances. One of the important methods in controller design for nonlinear systems; is designing based on the passivity concept. This concept which provides a useful tool for analysis of nonlinear systems has been also used for asymptotic stabilizing of nonlinear dynamical systems especially mechanical systems. The passivity-based control law is a static output feedback and has valuable features. Because of existence of uncertainties and external disturbances in the state-space of equations of physical systems; first the robust version of passivity-based control method, which is recently developed in literature, is given and the control law for nonlinear uncertain systems with affine structure is presented. Then, this approach is used in controller design for a spacecraft. Since, this paper considers only the stabilization of velocity and body rates, therefore the reduced-order model is extracted from the state-space equation of a spacecraft with six degree of freedom and then the robust control law is designed. Computer simulations show the efficiency of the proposed controller in robust asymptotic stabilizing of the velocity and body rate vectors of the spacecraft in the presence of uncertainties and external disturbances.
Tahere Binazadeh; Mohammad Hossein Shafiei; Elham Bazregarzadeh
Volume 8, Issue 1 , April 2015, , Pages 1-7
Abstract
This paper presents a novel approach in design of missile guidance law against highly maneuvering targets. This approach is based on the principles of partial stability and finite-time stability (finite-time partial stability). Also, it is shown that the designed guidance law is in conformity with a ...
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This paper presents a novel approach in design of missile guidance law against highly maneuvering targets. This approach is based on the principles of partial stability and finite-time stability (finite-time partial stability). Also, it is shown that the designed guidance law is in conformity with a real guidance scenario that leads to collision. In the design procedure the acceleration vector of the target is assumed as an external bounded disturbance and only this bound is required in the design of the guidance law. Therefore, the maneuver of the target is not restricted to any known and predetermined structure and measurement or estimation of the target acceleration vector during the maneuver is not necessary. The performance of the proposed guidance law is shown through analysis and computer simulations.