固定翼垂直起降无人机过渡机动优化控制分配研究

A nonlinear optimal control allocation method is proposed to solve the 6-degrees-of-freedom transition maneuver control of a novel fixed-wing vertical take-off and landing (VTOL) unmanned aerial vehicle (UAV). A global controller is designed using incremental nonlinear dynamic inversion (INDI) method. INDI method can be used to reduce the influence of uncertainty in control model on control system performance. On the basis of INDI method, a two-stage cascaded optimal control allocation method is proposed to allocate the increment of control variables in flight path and attitude control loops. The proposed method can be used to transform a nonlinear coupled control allocation problem into a linear optimization problem, which avoids iterative calculation and improves solution speed. A dynamic weight strategy is designed for the weight selection in objective function. The dynamic weight strategy can adjust weights according to flight states and mission requirement, ensuring the rationality of optimal allocation results. The simulated results indicate that UAV can track transition maneuver flight path successfully, and the control allocation method is feasible.