考虑输入受限的航天器安全接近姿轨耦合控制

Attitude and orbital coupled control of spacecraft safe approach considering input saturation

中文关键词  航天器安全接近  姿轨耦合控制  输入受限  避免碰撞  安全约束函数  滑模控制

英文关键词  spacecraft safe approach  attitude and orbital coupled control  input saturation  collision avoidance  safety constraint function  sliding mode control

中文摘要

      针对存在外部扰动和输入受限的航天器安全接近的问题, 当扰动上界未知时, 基于积分滑模控制理论设计了抗 饱和的有限时间自适应姿轨耦合控制器. 控制器的设计过程中采用了新型的避碰函数限制追踪航天器运动区域进而保 证接近过程中航天器的安全性, 同时通过辅助系统和自适应算法分别处理了输入受限和扰动上界未知. 借助李雅普诺夫 理论证明了在控制器的作用下系统状态在有限时间内收敛, 且能够保证追踪航天器在实现航天器接近的过程中不与目 标航天器发生碰撞. 最后通过数字仿真进一步验证了所设计控制器的有效性.

英文摘要

      For the problem of spacecraft safe approach with input saturation and external disturbances, by using the integral sliding mode control combined with potential function, an adaptive anti-saturation attitude and orbital coupled controller is proposed with unknown upper bound of external disturbances. In the process of controller design, a novel presented collision avoidance function is used to limit the motion area of the chaser spacecraft, which can guarantee the safety of the spacecrafts. At the same time, the auxiliary system and adaptive law are introduced to handle the input saturation and the unknown upper bound of external disturbances. Lyapunov theory is used to prove that the states of the closed-loop system under the designed controller can converge in finite time, and the chaser spacecraft under the control scheme can avoid collision with the target spacecraft in the process of realizing the spacecraft approach. Finally, simulations are conducted to further verify the effectiveness of the proposed control scheme.