【作者】 王光伦；

【导师】 张卯瑞；

【作者基本信息】 哈尔滨工业大学 ， 导航、制导与控制， 2010， 硕士

【摘要】 升力式高超声速飞行器具备较大的机动能力,可实现远程快速精确打击任务。由于再入环境复杂,再入轨迹具有非线性、强约束的特点,设计精度高、鲁棒性强的制导律有一定的难度。本文以研究升力式高超声速飞行器的再入制导技术为目标,以通用航空飞行器(CAV-H)为研究对象,在改进的气动模型下,研究了利用预测校正方法的再入制导律设计问题。论文首先根据再入过程的特点,在半速度坐标系下建立了三维再入运动方程,并分析了再入过程中所要满足的约束条件。为使仿真更加接近实际,气动模型需要有较高的精度。本文利用气动实验数据,在同时考虑攻角与速度因素的情况下,通过辨识得到了一种改进的气动模型,并与一般的攻角多项式模型进行了对比。利用改进的气动模型,本文进行了再入走廊及初始下降段的仿真。由于改进气动模型的引入,对比于一般的气动模型,本文分析了再入走廊和初始段轨迹的变化情况。针对再入走廊约束的施加问题,本文采取一种将再入走廊约束转化为控制变量约束的间接施加方法。本文为寻求较高的落点精度,将制导律的设计分两段进行。第I段,在纵向利用再入航程进行预测制导,在侧向设计横程边界使飞行器向目标飞行;第II段,纵向利用高度进行预测制导,侧向设计横程边界使飞行器到达目标点。最后通过仿真证明,该制导方法可在不同的初始条件下到达同一目标,并达到预定的落点精度。更多还原

【Abstract】 The lifting hypersonic vehicle has a high maneuverablity for the long-range precise strike mission. Due to the reentry environmental complexity and the trajectory’s nonlinearity and hard constraints, it is difficult to design a guidance law with high accuracy and robustness. In order to develop reentry guidance technology of the lifting hypersonic vehicle, based on the Common Aero Vehicle(CAV-H), this dissertation designs a guidance law using the predictor-corrector algorithm.First, according to the character of reentry process, this dissertation builds the 3DOF equations of motion and analyzes the path constrains.In order to make the simulation close to reality, an improved aerodynamic model as a function of velocity and angle of attack is identified based on aero database. To illustrate the accuracy, the comparison with the commen model is made.By using the improved aerodynamic model, the reentry corridor and the trajectory in initial descent are simulated. The changes of them under different models are also analyzed. To enforce the path contrains on designing the guidance law, an indirect inforcement method is utilized to convert the path constraints into control variables’constraints.The process of designing the guidance law is divided into two phases in order to seek for high impact point precision. In phase I, the predictor-corrector using downrange is applied in longitudinal guidance, and in lateral guidance, the crossrange threshold is designed to constrain the vehicle to fly to the destination approximately. In phase II, the height is used in the predictor-corrector for longitudinal guidance, and the lateral crossrange threshold is designed to make the vehicle reach the destination. Finally, the simulations confirm that the vehicle can reach the same destination with different initial conditions and meet the intended accuracy.更多还原