基于格网框架的舰载机极区惯性解算及弹射对准方法研究

The carrier aircraft need to carry out military action in polar region to protect our activity of resource exploration and channel development. The carrier aircraft rely on high precision navigation to reach the airspace and fight. Only inertial system can be used as the core navigation equipment in polar. But also faces two major challenges: first, true north azimuth towards failure as a reference method; second, the deck alignment is time-consuming and in-flight alignment is not reliable. Grid inertial navigation theory and catapult launching alignment algorithms are studied in this project. The grid coordinate is established by grid north which is defined by the grid reference baseline based on any one of meridian, completing grid inertia iteration algorithms. The angle between grid north and true north is used to design polar entrance and exit switching relations which could be applied to establish a unified inertial algorithm structure; the relationship between latitude and longitude error in geographical and position error in ECEF coordinate is revealed base on ellipsoidal model. Clear constraints are defined by the relative motion process analyses between the carrier and aircraft. The lever arm length is computed online to compensate ever arm error rely on spatial location relationship between the carrier and aircraft and the high precision velocity information. Sudden state changed kalman filter of revised filter gain and step prediction is proposed. Algorithms are verified and evaluated by simulation. Research results have important implications for the polar navigation theory development and technological progress.

为保护我国在北极的资源勘探和航道开发活动，航母舰载机须具备在极区开展军事行动的能力，而高精度导航是保障舰载机到达预定空域并作战的关键技术。只有惯性系统能作为极区核心导航设备，但仍面临两大挑战：一，真北方向作为航向参考方法失效；二，甲板对准耗时而空中对准不可靠。项目研究舰载机极区格网惯性导航理论和弹射对准方法。以任意子午线作为基准线定义格网北向，建立格网坐标系，完成极区格网导航数字算法；利用格网北向与真北方向的夹角，设计进出极区参数切换关系,形成统一的惯性解算结构；基于椭球模型ECEF位置误差和地理坐标系经纬度误差关系揭示格网导航误差传播特性。分析舰、机相对运动过程明确弹射对准约束条件；通过舰、机空间位置关系和速度信息在线计算杆臂长度，实现杆臂效应补偿；对滤波增益和一步预测修正，提出状态突变的卡尔曼滤波方法。采用数字仿真对算法进行验证和评估。研究成果对极区导航理论发展和技术进步具有重要意义。

惯性导航是保障航母舰载机在极区进行作战的核心导航设备，但是面临特殊问题：第一，极区经线收敛导致真北方向作为航向参考的惯性解算方法失效；第二，空中对准依赖的卫星导航信号不可靠。针对上述问题，本项目研究了极区格网惯性解算数字递推方法，根据导航模式参数切换关系，建立全球范围内形式统一的惯性导航理论，揭示椭球模型下格网惯性导航误差传播特性，建立了极区惯性导航椭球模型的误差方程，利用激光多普勒测速仪测量航母、舰载机相对速度以及航母速度的矢量作为基准信息，构建舰载机极区弹射对准方案。经过数字仿真分析表明：格网坐标系可以作为舰载机在极区飞行惯性结算的导航坐标系，使用速度匹配可以实现航母舰载机弹射起飞传递对准，测量误差在0.1m /s时，弹射对准的位置精度可以达到0.1m级，弹射对准方案中，杆臂误差可以基于舰机运动相对关系进行实时计算而补偿，弹射对准中的大失准角误差可以利用跑道航向信息转换为小失准角问题进行处理。研究成果为我国舰载机在极区飞行的惯导系统提供了理论支撑，为相关科研院所提供技术支撑并得到应用，有力的支撑了相关型号研制任务的顺利进行。