Purpose

The paper aims to address the combined attitude control and Sun tracking problem in a flexible spacecraft in the presence of external and internal disturbances. The attitude stabilization of a flexible satellite is generally a challenging control problem, because of the facts that satellite kinematic and dynamic equations are inherently nonlinear, the rigid–flexible coupling dynamical effect, as well as the uncertainty that arises from the effect of actuator anomalies.

Design/methodology/approach

To deal with these issues in the combined attitude and Sun tracking system, a novel control scheme is proposed based on the adaptive fuzzy Jacobian approach. The augmented spacecraft model is then analyzed and the Lyapunov-based backstepping method is applied to develop a nonlinear three-axis attitude pointing control law and the adaptation law.

Findings

Numerical results show the effectiveness of the proposed adaptive control scheme in simultaneously tracking the desired attitude and the Sun.

Practical implications

Reaction wheels are commonly used in many spacecraft systems for the three-axis attitude control by delivering precise torques. If a reaction wheel suffers from an irreversible mechanical breakdown, then it is likely going to interrupt the mission, or even leading to a catastrophic loss. The pitch-axis mounted solar array drive assemblies (SADAs) can be exploited to anticipate such situation to generate a differential torque. As the solar panels are rotated by the SADAs to be orientated relative to the Sun, the pitch-axis wheel control torque demand can be compensated by the differential torque.

Originality/value

The proposed Jacobian control scheme is inspired by the knowledge of Jacobian matrix in the trajectory tracking of robotic manipulators.

中文翻译：

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航天姿态与太阳跟踪组合系统的自适应模糊Jacobian控制。

目的

本文旨在解决存在外部和内部干扰的挠性航天器中姿态控制和太阳跟踪的组合问题。柔性卫星的姿态稳定通常是一个具有挑战性的控制问题，因为卫星运动学和动力学方程固有地是非线性的，刚柔耦合动力学效应以及执行器异常效应所引起的不确定性。

设计/方法/方法

针对姿态和太阳联合跟踪系统中的这些问题，提出了一种基于自适应模糊雅可比方法的控制方案。然后，分析了增强型航天器模型，并应用了基于Lyapunov的反推方法来开发非线性三轴姿态指向控制律和自适应律。

发现

数值结果表明，所提出的自适应控制方案在同时跟踪所需姿态和太阳时是有效的。

实际影响

反作用轮通常在许多航天器系统中用于通过提供精确的扭矩进行三轴姿态控制。如果反作用轮遭受不可逆的机械故障，那么它很可能会中断任务，甚至导致灾难性的损失。可以利用俯仰轴安装的太阳能电池阵列驱动组件（SADAs）来预测这种情况以产生差动扭矩。当太阳能电池板通过SADA旋转以相对于太阳定向时，俯仰轴车轮控制扭矩需求可以通过差动扭矩进行补偿。

创意/价值

提出的雅可比控制方案是受机器人操纵器轨迹跟踪中的雅可比矩阵知识的启发。