Design and Optimization of a Magnetically Levitated Inductive Reaction Sphere for Spacecraft Attitude Control

The inductive reaction sphere (RS) brings the benefit of simple, economical, and miniaturized design, and it is capable of multi-DOF torque generation. Thus, it is a suitable choice for the angular momentum exchange actuator in attitude control of micro-spacecrafts. To synthesize symmetric distribution of eddy currents and improve the speed and stability of rotation, a novel 4-pole winding design is proposed. However, the developed simplified analytical model shows that reduced pole number degrades the torque generation. To enhance the output torque of 4-pole RS, its curved cores and electromagnets are redesigned to enable the side teeth to be functional. As the analytical torque model for the RS with the slotted cores is not available, a constrained optimization problem is formulated, and the optimized parameters are calculated based on the prediction model from supported vector machine and finite element analysis. The lab prototypes are developed to validate the proposed design and test the speed performance. The experimental results show that the 4-pole RS prototype obtains a stable rotation over 700 rpm about X, Y and Z axis respectively with the angular momentum of 0.08 kg·m 2 /s, being superior to the 6-pole counterpart.

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Fault modeling of general momentum exchange devices in spacecraft attitude control systems

Journal of the Franklin Institute ◽

10.1016/j.jfranklin.2020.02.015 ◽

2020 ◽

Vol 357 (11) ◽

pp. 6407-6434

Author(s):

Chengfei Yue ◽

Qiang Shen ◽

Xibin Cao ◽

Feng Wang ◽

Cher Hiang Goh ◽

...

Keyword(s):

Control Systems ◽

Attitude Control ◽

Fault Modeling ◽

Spacecraft Attitude ◽

Spacecraft Attitude Control ◽

Momentum Exchange

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Design of an Adaptive Singularity-Free Control Moment Gyroscope (ASCMG) Cluster for Spacecraft Attitude Control

Volume 1: Adaptive and Intelligent Systems Control; Advances in Control Design Methods; Advances in Non-Linear and Optimal Control; Advances in Robotics; Advances in Wind Energy Systems; Aerospace Applications; Aerospace Power Optimization; Assistive Robotics; Automotive 2: Hybrid Electric Vehicles; Automotive 3: Internal Combustion Engines; Automotive Engine Control; Battery Management; Bio Engineering Applications; Biomed and Neural Systems; Connected Vehicles; Control of Robotic Systems ◽

10.1115/dscc2015-9818 ◽

2015 ◽

Cited By ~ 1

Author(s):

Sasi Prabhakaran Viswanathan ◽

Amit K. Sanyal

Keyword(s):

Angular Momentum ◽

Finite Number ◽

Attitude Control ◽

Degrees Of Freedom ◽

Spacecraft Attitude ◽

Spacecraft Attitude Control ◽

Dynamics Model ◽

Control Moment Gyroscope ◽

Control Moment ◽

Control Scheme

Spacecraft attitude control using an Adaptive Singularity-free Control Moment Gyroscope (ASCMG) cluster design for internal actuation is presented. A complete dynamics model is derived using the principles of variational mechanics, relaxing some common assumptions made in prior literature on control moment gyroscopes. These assumptions include perfect axisymmetry of the rotor and gimbal structures, and perfect alignment of the centers of mass of the gimbal and the rotor. The resulting dynamics display complex nonlinear coupling between the internal degrees of freedom associated with the CMG and the spacecraft base body’s rotational degrees of freedom in the absence of these assumptions. This dynamics model is further generalized to include the effects of multiple CMGs placed in the spacecraft bus, and sufficient conditions for non-singular CMG cluster configurations are obtained. General ideas on control of the angular momentum of the spacecraft using changes in the momentum variables of a finite number of CMGs, are provided. A control scheme using a finite number of CMGs in the absence of external torques and when the total angular momentum of the spacecraft is zero, is presented. The dynamics model of the spacecraft with a finite number of CMGs is then simplified under the assumption that the rotor is axisymmetric, in which case it is shown that singularities are avoided. As an example, the case of three CMGs with axisymmetric rotors, placed in a tetrahedron configuration inside the spacecraft, is considered. The control scheme is then numerically implemented using a geometric variational integrator and the results confirm the singularity-free property and high control authority of the ASCMG cluster. Moreover, as rotor misalignments are addressed in the dynamics model, the ASCMG cluster can adapt to them without requiring hardware changes.

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