主要研究存在禁止姿态的航天器自主姿态机动控制问题。首先,给出航天器的动力学和运动学模型,利用四元数描述航天器与机动姿态和禁止姿态的姿态偏差,用相应的欧拉转角描述不同姿态间的距离。为利用势函数完成禁止姿态回避,结合航天器的运动情况设计排斥势函数(RPF)存在条件后,根据禁止姿态最小允许夹角构造一种新的排斥势函数。接着,利用排斥及吸引势函数(APF)的共同作用得到虚拟指令角速度,利用反步法得到自主姿态机动控制器。此外,针对控制受限问题给出控制参数自适应规则,并设计回避势函数局部极小值情况的切换控制器。最后,通过对不同禁止姿态区域的数学仿真,验证了设计方法的有效性和通用性。
This article investigates the spacecraft autonomous attitude maneuver control in the presence of forbidden attitude.First,the dynamical and kinematic equations are introduced,in which a quaternion is adopted to represent the attitude deviation between the spacecraft attitude and maneuver or the forbidden attitude,with the corresponding Euler rotation angles describing the distance of various attitudes.Second,in order to avoid the forbidden attitude,the existence conditions for the repulsive potential function(RPF) are exploited by incorporating the spacecraft motions,and a novel RPF is proposed according to the minimum separation angle allowed for the forbidden attitude.The RPF as well as the attractive potential function(APF) are employed subsequently to derive a virtual angular velocity command.An autonomous attitude maneuver controller is obtained by means of backstepping.Meanwhile,some self-adaptive rules for the control parameters are developed to deal with control saturation.In addition,one switch controller is proposed to overcome the local minima of the potential function.Finally,numerical results for different forbidden attitude regions are presented to show the effectiveness and generality of the proposed method.