滑翔式飞行器再入制导与控制方法研究

发布时间：2019-05-23 12:02

【摘要】：滑翔式飞行器以高超声速进入大气层，并于再入过程中采用无动力飞行。由于具有相对较高的升阻比，滑翔式飞行器拥有良好的机动能力，制导控制系统可以通过改变升力的方向来控制其飞行轨迹。然而，再入段的飞行任务多变、飞行时间长、速度和位置变化大、飞行环境变化剧烈等特点，给滑翔式飞行器再入制导和控制系统的设计带来困难和挑战。本文研究滑翔式飞行器再入的制导和控制方法，研究着眼于以下三方面：在线轨迹规划、轨迹跟踪制导、再入姿态控制。所研究的内容主要分为如下四部分：第一，提出了一种新的可以满足地理约束以及其他路径约束的三维自主再入制导律。该制导律可以分为轨迹规划器和轨迹跟踪器。轨迹规划器可以在线规划参考轨迹。在规划过程中，，将参考轨迹分为初始下降段和滑翔段。初始下降段的轨迹规划采用定常攻角和倾侧角策略设计。滑翔段的轨迹规划同时考虑飞行器的纵向运动和侧向运动。在阻力加速度-能量平面内，纵向子规划器通过对再入走廊的上下界插值来生成可行的参考轨迹。倾侧角大小可以通过参考阻力加速度剖面计算，而倾侧角符号则是由侧向子规划器确定的。侧向子规划器针对航路点约束采用两次倾侧角反转策略，针对禁飞区约束采用动态方向角误差走廊策略。轨迹规划需要反复迭代使用纵向子规划器和侧向子规划器，直至生成的参考轨迹满足所有的路径约束。在轨迹跟踪方面，提出了一种新的基于自抗扰控制的再入轨迹跟踪制导律。此外，对所提出再入制导方法进行了适应性测试和Monte Carlo数值仿真，结果表明所提出的制导方法能够适应不同的飞行任务，并能在满足地理约束下使滑翔式飞行器精确飞至目标点。第二，为了提高再入制导律的实时性和鲁棒性，提出一种基于滚动时域控制和间接Legendre伪谱法的轨迹跟踪制导律。首先将参考轨迹的跟踪问题转化为轨迹状态调节问题，从而获得一个线性时变系统的最优控制问题；然后采用滚动时域控制结合基于间接Legendre伪谱法的最优反馈控制算法设计出一种易于在线实现的制导律。基于上述工作完成了亚轨道滑翔式飞行器制导过程的3自由度数值仿真研究工作。数值仿真结果表明该制导方法在初始点状态存在较大范围偏差和气动参数存在较大误差的情况下具有良好的鲁棒性。第三，研究在大范围系统不确定和外界扰动下滑翔式飞行器的有限时域姿态控制问题，同时需要考虑冗余舵的分配。首先，利用反馈线性化技术消除运动方程的非线性，从而建立姿态控制器的基本模型。然后，基于该基本模型，提出两种结合扰动观测器的时变滑模控制方法。一种方法基于边界层方法，另一种方法基于一种新的二阶滑模控制方法。对两种方法形成的闭环系统分别进行了有限时域稳定性分析。最后，当姿态控制器生成力矩指令后，引入一种优化控制分配方法将力矩指令分配至空气动力舵和脉冲反作用力控制系统舵上。数值仿真结果表明两种基于扰动观测器的时变滑模控制方法均能够消除抖振现象，同时对系统不确定和外界干扰具有较强的鲁棒性。此外，所提出的二阶滑模控制方法具有更高的控制精度。最后，为了应对再入飞行时的飞行故障，提出了一种主动容错控制策略。所提出的主动容错控制策略包括飞行故障检测方法和再入姿态控制器重构两部分。首先，建立故障存在时的飞行器动力学模型。然后，设计一种非线性鲁棒故障检测观测器，实现对飞行故障的及时观测。最后，结合自适应控制和滑模控制提出一种应对故障的控制律，一旦检测到飞行故障，控制律就切换为所提出自适应滑模控制，从而完成姿态控制器的重构。数值仿真算例将主动容错策略与经典方法进行对比，结果表明所提出的容错控制在出现飞行故障的情况下仍具有良好的控制效果。
[Abstract]:The glide-type aircraft enters the atmosphere at a high supersonic speed and has no power to fly during re-entry. Because of the relatively high lift-to-drag ratio, the glide-type aircraft has a good maneuverability, and the guidance control system can control its flight trajectory by changing the direction of the lift. However, the design of the reentry guidance and control system of the glide-type aircraft brings difficulties and challenges to the design of the reentry guidance and control system of the glide-type aircraft. In this paper, the guidance and control methods for reentry of glide-type aircraft are studied. The following three aspects are focused on: on-line trajectory planning, trajectory tracking guidance and re-entry attitude control The content of the research is divided into four parts: In the first part, a new three-dimensional autonomous re-entry which can meet the geographical constraints and other path constraints is proposed. A guidance law. The guidance law can be divided into a track planner and a track. The tracker. The track planner can plan the parameters online In the planning process, the reference track is divided into an initial section and an initial section. Gliding section. The trajectory planning of the initial section is the steady angle of attack and the angle of the roll. The trajectory planning of the glide section takes into account the longitudinal movement and the side of the aircraft in the resistance acceleration-energy plane, the longitudinal sub-planner generates a feasible reference by interpolating the upper and lower bounds of the re-entry corridor The angle of the roll angle can be calculated by the reference resistance acceleration profile, and the roll angle symbol is calculated by the lateral subplan It is determined that the lateral sub-planner adopts the two-roll angle inversion strategy for the waypoint constraint, and the dynamic direction angle error is adopted for the no-fly zone constraint. Corridor strategy. The trajectory planning requires repeated iterations to use the longitudinal and lateral sub-planters until the generated reference track meets all the paths In the aspect of track tracking, a new reentry trajectory tracking based on self-disturbance control is proposed. In addition, the adaptive test and the Monte Carlo numerical simulation of the proposed reentry guidance method are carried out. The results show that the proposed guidance method can adapt to different flight tasks, and can make the glide-type aircraft to fly accurately under the constraints of geographical constraints. Secondly, in order to improve the real-time and robustness of reentry guidance law, a track based on rolling time domain control and indirect Legendre pseudospectral method is proposed. The tracking problem of a linear time-varying system is obtained by converting the tracking problem of a reference track into a track state adjustment problem, and then a rolling time-domain control is adopted to design an optimal feedback control algorithm based on the indirect Legendre pseudo-spectrum method to design an easy on-line real-time control method. The three-degree-of-freedom numerical simulation of the guidance process of the suborbital glide-type aircraft is completed based on the above-mentioned work The numerical simulation results show that the guidance method is good in the condition of large deviation of the initial point state and the large error of the aerodynamic parameters. Good robustness. Third, it is necessary to study the limited time-domain attitude control of the glide-type aircraft under the uncertainty of the large-range system and the external disturbance. First, the feedback linearization technique is used to eliminate the non-linearity of the motion equation, so that the attitude control is established. and then, based on the basic model, Variable-mode control method. One method is based on boundary layer method, and the other is based on a new method. Step-mode control method is used to control the closed-loop system formed by two methods, respectively. In the end, when the attitude controller generates the torque command, an optimal control assignment method is introduced to distribute the torque command to the aerodynamic rudder and the impulse reaction The numerical simulation results show that the two kinds of time-varying sliding mode control methods based on the disturbance observer can eliminate the buffeting phenomenon, and at the same time, the system uncertainty and the external interference and the proposed second-order sliding mode control method has the advantages of high robustness, Higher control accuracy. Finally, in order to deal with the flight fault during the reentry flight, a new method is presented. Active fault-tolerant control strategy is proposed in this paper. The proposed active fault-tolerant control strategy includes flight fault detection and re-entry. The state controller reconstructs two parts. First, when the fault exists, and then designing a non-linear robust fault detection observer, In the end, the control law of the fault is proposed in combination with the adaptive control and the sliding mode control. Once the flight fault is detected, the control law is switched to the proposed adaptive sliding mode control. The numerical simulation example compares the active fault-tolerant strategy with the classical method, and the result shows that the proposed fault-tolerant control is still under the condition of flight failure.
【学位授予单位】：北京理工大学
【学位级别】：博士
【学位授予年份】：2015
【分类号】：V448.2

【参考文献】