Coupled orbit-attitude dynamics and trajectory tracking control for spacecraft electromagnetic docking

The dynamic modeling and trajectory tracking control of a mobile robot is handled by a hierarchical constraint approach in this study. When the wheeled mobile robot with complex generalized coordinates has structural constraints and motion constraints, the number of constraints is large and the properties of them are different. Therefore, it is difficult to get the dynamic model and trajectory tracking control force of the wheeled mobile robot at the same time. To solve the aforementioned problem, a creative hierarchical constraint approach based on the Udwadia–Kalaba theory is proposed. In this approach, constraints are classified into two levels, structural constraints are the first level and motion constraints are the second level. In the second level constraint, arbitrary initial conditions may cause the trajectory to diverge. Thus, we propose the asymptotic convergence criterion to deal with it. Then, the analytical dynamic equation and trajectory tracking control force of the wheeled mobile robot can be obtained simultaneously. To verify the effectiveness and accuracy of this methodology, a numerical simulation of a three-wheeled mobile robot is carried out.

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Adaptive Trajectory Tracking Control for a Rehabilitative Training Walker with Center of Gravity Shift

2020 2nd International Conference on Industrial Artificial Intelligence (IAI) ◽

10.1109/iai50351.2020.9262159 ◽

2020 ◽

Author(s):

Hongbin Chang ◽

Xiaojie Su ◽

Shuoyu Wang

Keyword(s):

Trajectory Tracking ◽

Tracking Control ◽

Center Of Gravity ◽

Trajectory Tracking Control

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Robust finite-time trajectory tracking control for a space manipulator with parametric uncertainties and external disturbances

Proceedings of the Institution of Mechanical Engineers Part G Journal of Aerospace Engineering ◽

10.1177/09544100211014754 ◽

2021 ◽

pp. 095441002110147

Author(s):

Qijia Yao

Keyword(s):

Trajectory Tracking ◽

Finite Time ◽

Tracking Control ◽

Disturbance Observer ◽

Control Method ◽

Parametric Uncertainties ◽

External Disturbances ◽

Trajectory Tracking Control ◽

Space Manipulator ◽

Tracking Controller

Space manipulator is considered as one of the most promising technologies for future space activities owing to its important role in various on-orbit serving missions. In this study, a robust finite-time tracking control method is proposed for the rapid and accurate trajectory tracking control of an attitude-controlled free-flying space manipulator in the presence of parametric uncertainties and external disturbances. First, a baseline finite-time tracking controller is designed to track the desired position of the space manipulator based on the homogeneous method. Then, a finite-time disturbance observer is designed to accurately estimate the lumped uncertainties. Finally, a robust finite-time tracking controller is developed by integrating the baseline finite-time tracking controller with the finite-time disturbance observer. Rigorous theoretical analysis for the global finite-time stability of the whole closed-loop system is provided. The proposed robust finite-time tracking controller has a relatively simple structure and can guarantee the position and velocity tracking errors converge to zero in finite time even subject to lumped uncertainties. To the best of the authors’ knowledge, there are really limited existing controllers can achieve such excellent performance under the same conditions. Numerical simulations illustrate the effectiveness and superiority of the proposed control method.

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