微小卫星多约束姿态机动规划方法

Path Maneuver Planning for a Microsatellite with Multiple Constraints

针对微小卫星姿态控制中存在的多重指向约束和角速率约束问题,提出一种基于对数型势函数的多约束姿态机动规划方法。首先针对微小卫星携带的光学传感器需躲避强光天体而天线需指向地面保证对地通信这一约束特性,采用对数型势函数方法保证约束姿态指向满足任务要求;其次,针对姿态角速率限制的问题,引入障碍Lyapunov函数确保姿态角速率始终处于约束范围内。与在线优化方法相比,该方法具有计算量小的显著优势,非常适合星上处理能力有限的微小卫星。此外,考虑外界干扰力矩的影响,引入自适应干扰估计律,增强了控制系统的鲁棒性。最后,通过数学仿真对本文方法进行了校验,仿真结果表明,该方法能够快速实现卫星姿态机动到期望指向,与此同时,在整个姿态机动过程中,均满足多重指向约束和姿态角速率约束要求。

An attitude slew maneuver control based on the logarithmic convex potential function is proposed for a microsatellite with multiple attitude and angular velocity constraints.Since the mission requirements,the optical instruments equipped on the microsatellites are required to point their boresight without direct exposure to the bright objects while the high-gain antenna must point to the ground for maintaining the communications.In this paper,the logarithmic convex potential function is introduced to solve the attitude path planning issue and the angular velocity constraint problem is also well tackled by the fixed barrier Lyapunov function.Compared with the on-line optimization method,the proposed method can reduce the computation burden and it is very fit for a microsatellite with low computation ability.In addition,the disturbance moments are taken into account and the nonlinear adaptive disturbance observer is inserted into the control law in order to enhance the robust capability.Finally,the simulations demonstrate that the pointing constraints are properly avoided and the desired attitudes are obtained by the proposed control method without violating the angular velocity constraints.