空基回收拖曳系统直线-盘旋转接段运动轨迹设计

Trajectory design for straight-circulating flight transition of aerial recovery towing system

针对气流扰动下空基回收拖曳系统在直线-盘旋转接段飞行过程中的拖曳浮标稳定问题,提出一种基于微分平坦理论的拖曳系统转接段运动轨迹的设计方法,通过设计母机运动轨迹间接地控制拖曳浮标沿着预设的转接轨迹安全、平稳、精准地转接飞行。采用质点-弹簧离散缆绳模型构建母机-缆绳-浮标组合体多体动力学模型;在证明拖曳系统具备微分平坦特性的基础上,以拖曳浮标三轴位置为平坦输出,所提方法以期浮标沿着预设安全转接段轨迹飞行;结合拖曳浮标直线飞行状态与盘旋飞行状态设计拖曳浮标转接段飞行轨迹。通过平静大气、多种常值风及阵风气流扰动场景下的仿真算例结果表明,所提方法能够实现拖曳浮标在直线-盘旋转接段的稳定飞行。

To handle the stabilization problem of the towed buoy in the straight-circulating flight transition process of the aerial recovery towing system under airflow disturbances,a trajectory design method for the transition process of the towing system based on differential flatness theory was proposed.By designing the trajectory of the mothership,the towed buoy was indirectly controlled to fly safely,smoothly,and accurately along the preset transition trajectory.Firstly,the mass-spring discrete cable model was used to construct the multi-body dynamic model of the mothership-cable-buoy.Secondly,after proving that the towing system was differentially flat,a trajectory design method of the towing system based on differential flatness theory was proposed by taking the three-axis position of the towed buoy as the flat output so that the buoy could fly along the preset safe transition trajectory.Subsequently,the straight and circulating flight states of the towed buoy were analyzed to design the flight trajectory of the towed buoy in the transition section.Finally,the simulation examples under a calm atmosphere,various constant wind,and gust turbulence scenarios show that the proposed method can achieve stable flight of the towed buoy in the straightcirculating transition section.