The Experts below are selected from a list of 6234 Experts worldwide ranked by ideXlab platform

M. Barati - One of the best experts on this subject based on the ideXlab platform.

  • Mathematical modeling and simulation of the earth's magnetic field: A comparative study of the models on the spacecraft attitude control application
    Applied Mathematical Modelling, 2017
    Co-Authors: M. Navabi, M. Barati
    Abstract:

    Abstract In this paper, the Earth's magnetic field models which are widely used in spacecraft attitude control applications are modeled and extensively compared with a reference model. The reference model is obtained utilizing coefficients from the last generation of International Geomagnetic Reference Field (IGRF-12). The validity of this model is verified with the World Magnetic Model (WMM) in terms of intensity and direction of the field. The reference model is then used to evaluate lower-order and approximating models while the influence of effective parameters such as expansion order of modeling, orbit height, inclination, latitude and longitude on accuracy of modeling is investigated. The simulation results for several scenarios are presented and discussed. The linear and nonlinear transformations of the models from Orbital Frame to spacecraft body Frame are compared for a wide range of attitude angles in order to investigate the sensibility and validity of linear transformation. Simulation of a spacecraft attitude control maneuver is performed to demonstrate the importance of the accuracy of the magnetic field model which is implemented in the attitude control system. The results indicated a meaningful increase in control effort when a simplified model was used. This research was aimed to investigate the borders of different geomagnetic field models and transformations for spacecraft attitude control applications. The presented results may lead to a proper choice of the Earth's magnetic field model based on the space mission requirements.

A. A. Tikhonov - One of the best experts on this subject based on the ideXlab platform.

  • Stabilization of a programmed rotation mode for a satellite with electrodynamic attitude control system
    Advances in Space Research, 2018
    Co-Authors: A. Yu. Aleksandrov, E. B. Aleksandrova, A. A. Tikhonov
    Abstract:

    Abstract The paper deals with a dynamically symmetric satellite in a circular near-Earth orbit. The satellite is equipped with an electrodynamic attitude control system based on Lorentz and magnetic torque properties. The programmed satellite attitude motion is such that the satellite slowly rotates around the axis of its dynamical symmetry. Unlike previous publications, we consider more complex and practically more important case where the axis is fixed in the Orbital Frame in an inclined position with respect to the local vertical axis. The satellite stabilization in the programmed attitude motion is studied. The gravitational disturbing torque acting on the satellite attitude dynamics is taken into account since it is the largest disturbing torque. The novelty of the proposed approach is based on the usage of electrodynamic attitude control system. With the aid of original construction of a Lyapunov function, new conditions under which electrodynamic control solves the problem are obtained. Sufficient conditions for asymptotic stability of the programmed motion are found in terms of inequalities for the values of control parameters. The results of a numerical simulation are presented to demonstrate the effectiveness of the proposed approach.

  • Electrodynamical compensation of disturbing torque and attitude stabilization of a satellite in J2 perturbed orbit
    Acta Astronautica, 2017
    Co-Authors: A. A. Tikhonov, K.a. Antipov, D.g. Korytnikov, D.yu. Nikitin
    Abstract:

    Abstract The paper deals with a satellite in a circular near-Earth orbit, perturbed due to J 2 Earth's oblateness. The satellite interacts with the geomagnetic field by the moments of Lorentz and magnetic forces. The octupole approximation of the Earth's magnetic field is used. The possibility of electrodynamical attitude control for the satellite's stabilization in the Orbital Frame is analyzed. Once the problem of electrodynamical compensation of disturbing torque is solved, we can obtain the control algorithms for the satellite electromagnetic parameters which allows to stabilize the satellite attitude position in the Orbital Frame in the presence of disturbing gravity gradient torque. The total stability of the satellite programmed motion is proved analytically and verified by computer modeling.

  • Asymptotic stability of a satellite with electrodynamic attitude control in the Orbital Frame
    Acta Astronautica, 2017
    Co-Authors: A. Yu. Aleksandrov, A. A. Tikhonov
    Abstract:

    Abstract A satellite in a circular near-Earth orbit is under consideration. The three-axis stabilization of the satellite in the Orbital coordinate system with the use of electrodynamic attitude control system is studied. No constraints are imposed on the Earth's magnetic field approximation. The gravity gradient disturbing torque acting on the satellite attitude dynamics is taken into account as the largest disturbing torque. With the use of the Lyapunov direct method, conditions under which electrodynamic control solves the problem are obtained. The restrictions on the control parameter values for which one can guarantee the asymptotic stability of the programmed satellite motion are found and represented in an explicit form. Comparison of the results of numerical simulation and analytical investigation demonstrate effectiveness of the proposed approach.

  • On satellite electrodynamic attitude stabilization
    Aerospace Science and Technology, 2014
    Co-Authors: K.a. Antipov, A. A. Tikhonov
    Abstract:

    Abstract The paper deals with a satellite in a circular near-Earth orbit. The satellite interacts with the geomagnetic field by the Lorentz and magnetic torques. The gravitational disturbing torque acting on the satellite attitude dynamics is taken into account as the largest disturbing torque. The octupole approximation of the Earth's magnetic field is used. Satellite electromagnetic parameters, namely the electrostatic charge moment of the first order and the intrinsic magnetic moment are the controlled quasiperiodic functions. Control algorithms for the satellite electromagnetic parameters, which allow the satellite attitude position to be stabilized in the Orbital Frame were obtained. The cases of direct and indirect equilibrium positions in the Orbital Frame are investigated. The total stability of the satellite stabilized orientation is proved both analytically and by PC computations.

  • On the satellite's electrodynamic attitude stabilization
    2013
    Co-Authors: K.a. Antipov, A. A. Tikhonov
    Abstract:

    The paper deals with a satellite in a circular near-Earth orbit. The problem under consideration is the satellite’s attitude stabilization. The control algorithms for the spacecraft electromagnetic parameters, which allow to stabilize the spacecraft attitude position in the Orbital Frame are obtained. The direct Lyapunov method and the developed approach for the Lyapunov functions construction are used, the sucient conditions of the asymptotic stability of the satellite programmed motion in the Orbital coordinate system are obtained. The analytical treatment of the problem is based on nonlinear dierential equations of the satellite’s attitude motion.The disturbing eect of the gravitational moment is taken into account. At the same time the software complex was designed for comprehensive analysis of problems concerning the satellite attitude dynamics in geophysical fields. The report describes the complex as a complete software product. 1 Electro-dynamical attitude control system The paper deals with a satellite in a circular near-Earth orbit. The problem under consideration is the satellite’s attitude stabilization. The satellite is equipped with electrically charged shield with the total charge Q and possesses the intrinsic magnetic moment I. The charge center position, determined by vector 0 in the Frame, rigidly connected with the satellite, and the intrinsic magnetic moment I are under control. When the spacecraft is moving through the Earth’s magnetic field with the magnetic induction B the interaction of the shield charge with the geomagnetic field results in Lorentz forces excitation. The principal moment of these forces with respect to the satellite’s mass center may be approximated by the formula [1]

M. Navabi - One of the best experts on this subject based on the ideXlab platform.

  • Mathematical modeling and simulation of the earth's magnetic field: A comparative study of the models on the spacecraft attitude control application
    Applied Mathematical Modelling, 2017
    Co-Authors: M. Navabi, M. Barati
    Abstract:

    Abstract In this paper, the Earth's magnetic field models which are widely used in spacecraft attitude control applications are modeled and extensively compared with a reference model. The reference model is obtained utilizing coefficients from the last generation of International Geomagnetic Reference Field (IGRF-12). The validity of this model is verified with the World Magnetic Model (WMM) in terms of intensity and direction of the field. The reference model is then used to evaluate lower-order and approximating models while the influence of effective parameters such as expansion order of modeling, orbit height, inclination, latitude and longitude on accuracy of modeling is investigated. The simulation results for several scenarios are presented and discussed. The linear and nonlinear transformations of the models from Orbital Frame to spacecraft body Frame are compared for a wide range of attitude angles in order to investigate the sensibility and validity of linear transformation. Simulation of a spacecraft attitude control maneuver is performed to demonstrate the importance of the accuracy of the magnetic field model which is implemented in the attitude control system. The results indicated a meaningful increase in control effort when a simplified model was used. This research was aimed to investigate the borders of different geomagnetic field models and transformations for spacecraft attitude control applications. The presented results may lead to a proper choice of the Earth's magnetic field model based on the space mission requirements.

  • Earth’s Magnetic Field for Spacecraft Attitude Control Applications (TECHNICAL NOTE)
    International Journal of Engineering Transactions B: Applications, 2015
    Co-Authors: M. Navabi, N. N. Kamran
    Abstract:

    In this paper the earth’s magnetic field is simulated precisely while the intensity and direction of the field are verified with one of the standard references for selected points on the earth and the results are compared with some low-order models. In another simulation, the complete model is compared with a common approximate model. The magnetic field in Orbital Frame is described and to employ earth’s magnetic field in spacecraft attitude control applications, it is transferred into the spacecraft body Frame. Transformation between Orbital Frame and body Frame can be linear or nonlinear; the validity of linear transformation is investigated regarding various attitude angles. The divergence plots and the plot and table of error percentage illustrate the result based on the defined acceptable error.

Wei Huo - One of the best experts on this subject based on the ideXlab platform.

  • Terminal Sliding Mode Control for Space Rendezvous and Docking
    2015 International Conference on Computational Intelligence and Communication Networks (CICN), 2015
    Co-Authors: Shang Liu, Wei Huo
    Abstract:

    The relative motion control for spacecraft rendezvous and docking is considered. The relative position dynamics described in the target spacecraft's Orbital Frame, and attitude dynamics of the chaser spacecraft described in the chaser body Frame are all formulated in Euler-Lagrange forms. Based on property analysis of the coupled dynamic model a terminalb sliding mode control law is designed for the chaser with modeling uncertainties and external disturbances by using the Lyapunov redesign method. It is proved that the close-loop tracking error convergences to zero in finite time. Numerical simulation demonstrates effectiveness of the proposed control law.

  • 6-DOF integrated adaptive backstepping control for spacecraft proximity operations
    IEEE Transactions on Aerospace and Electronic Systems, 2015
    Co-Authors: Liang Sun, Wei Huo
    Abstract:

    Relative motion control with 6 degrees of freedom (6 DOF) is investigated for a chaser spacecraft with parametric uncertainties to approach an unknown tumbling space target. Unlike the conventional relative motion model described in the target Orbital Frame, the relative motion model formulated in the chaser’s body-fixed Frame can simplify modeling and control design for spacecraft proximity operations, while the chaser’s thrust misalignment and the natural couplings between relative translation and relative rotation are considered in the 6-DOF integrated dynamics. After the coupled relative motion dynamics are modeled, a 6-DOF integrated state feedback controller is designed by combining the classical backstepping technique with a simple norm-estimation adaptive method to achieve good control performance and decrease the computational burden. The chaser’s and target’s unknown inertial parameters, unknown thrust misalignment, and upper bound of unknown disturbances are estimated by online adaptive laws. Ultimately, uniformly bounded convergence of the relative position and relative attitude is proved via Lyapunov analysis. The performance of the proposed controller is demonstrated through numerical simulations.

Roberto Lampariello - One of the best experts on this subject based on the ideXlab platform.

  • ACC - Tube-Based Model Predictive Control for the Approach Maneuver of a Spacecraft to a Free-Tumbling Target Satellite
    2018 Annual American Control Conference (ACC), 2018
    Co-Authors: Caroline Buckner, Roberto Lampariello
    Abstract:

    We present a tracking controller for the rendezvous of a robotic chaser satellite to a free-tumbling target satellite in the presence of uncertainty in the predicted target motion, applicable in real-time. The maneuver to be controlled is modeled on the e.Deorbit scenario. The path followed by the chaser in the Orbital Frame is based on a prediction of the target motion and is provided by a motion planner. For the robust control of the maneuver, a linear tube-based robust model predictive controller is proposed, which will guarantee feasibility and stability for a predefined uncertainty in the target motion. The control problem is itself linear, permitting controller formulation using the linear Framework. However, the relation between the uncertainties of the maneuver participants is nonlinear, which complicates the controller design. The controller is evaluated in simulation, the results of which depict its effectiveness for a realistic uncertainty boundary.