针对多操纵面飞机存在的气动冗余控制分配问题,提出了一种基于最大方向导数增量(Max Direction Derivative Increment,MDDI)不动点(Fixed-point,FXP)的二次规划优化策略;首先,讨论了基于FXP的二次规划;接着,给出了MDDIFXP算法,通过计算当前迭代点沿各个方向的导数获得MDD,取前一迭代点和当前迭代点在MDD上的迭代增量作为当前迭代点的更新迭代增量;随后,证明了MDDIFXP算法的收敛性;最后,通过对不同控制分配优化方法的仿真验证,表明该改进优化算法MDDIFXP的有效性,以及相比原FXP算法的快速性。
Analytic redundancy-based fault diagnosis technique (ARFDT) is applied to onboard maintenance system (OMS). The principle of the proposed ARFDT scheme is to design a redundancy configuration using ARFDT to enhance the functions of redundancy management and built in test equipment (BITE) monitor. Redundancy configuration for dual-redundancy and analytic redundancy is proposed, in which, the fault diagnosis includes detection and isolation. In order to keep the balance between rapid diagnosis and binary hypothesis, a filter together with an elapsed time limit is designed for sequential probability ratio test (SPRT) in the process of isolation. Diagnosis results would be submitted to central maintenance computer (CMC) together with BITE information. Moreover, by adopting reconstruction, the designed method not only provides analytic redundancy to help redundancy management, but also compensates the output when both of the sensors of the same type are faulty. Our scheme is applied to an aircraft's sensors in a simulation experiment, and the results show that the proposed filter SPRT (FSPRT) saves at least 50% of isolation time than Wald SPRT (WSPRT). Also, effectiveness, practicability and rapidity of the proposed scheme can be successfully achieved in OMS.
