涵道风扇式无人机是一种冗余配置操纵面的飞行器,其控制分配问题通常使用伪逆法求解,然而伪逆法不能对任意可达的期望力矩都返回容许控制,使冗余的操纵面牺牲了部分控制能力。提出一种优先级控制分配方法,该方法先对期望力矩进行矢量分解并划分优先级,再求解约束最优化问题得到容许控制。相比于伪逆法,所提出的方法可对更大范围的期望力矩返回容许控制,而且当期望力矩不可达时,可以防止系统因执行器饱和而产生输出耦合。将所提出的方法应用到涵道风扇式无人机的控制分配中,仿真及飞行试验验证了该方法的有效性。
Ducted fan UAVs, aircraft with redundant control surfaces, usually solve the control allocation problem via the pseudo-inverse method. However, this method cannot return admissible control for all the moments in the Attainable Moment Set (AMS), therefore sacrificing partial control ability of redundant control surfaces. To solve this problem, this paper proposes a prioritized control allocation method, which first decomposes the desired moments into a sequence of prioritized partitions, followed by solution of the constrained optimization problem to obtain admissible control. Compared with the pseudo-inverse method, the proposed method can return admissible control for a larger range of desired moments. In addition, when the desired moments are unattainable, it can prevent the system from output coupling caused by actuator saturation. The proposed method is applied to the control allocation of ducted fan UAVs. Simulation and experiments verify the effectiveness of the method.
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