Integrated Game Based Guidance with Nonlinear Autopilot Design for Maneuvering Target Interception

The integrated game theory based guidance law with nonlinear autopilot (GGNA) system is presented in this paper. The guidance law is designed based on linear differential game theory while considering the motion of the target in 3‐D space such that the distance between the missile and the target is minimized faster than before. The autopilot system based on quaternion representation is developed using sliding mode control method to generate the attitude command. The stability of the integrated guidance and nonlinear autopilot system is analyzed with Lyapunov stability theory. In addition, this research assumes wingless missiles in our context in order to reduce the nonlinear effect from the aerodynamics. Furthermore, in order to extend the operation range of missiles from endo‐atmosphere to exo‐atmosphere, the missiles are equipped with Thrust Vector Control (TVC) mechanisms and Divert Control System (DCS). Finally, extensive simulations incorporating aerodynamic models are demonstrated to verify the validity of the proposed integrated guidance/autopilot systems. Moreover, the simulation results reveal that the mission of intercepting a maneuvering target is successfully accomplished.     

Extended trajectory shaping guidance law considering a first-order autopilot lag

To satisfy the terminal position and impact angel constraints, an optimal guidance problem was discussed for homing missiles. For a stationary or a slowly moving target on the ground, an extended trajectory shaping guidance law considering a first-order autopilot lag (ETSGL-CFAL) was proposed. To derive the ETSGL-CFAL, a time-to-go-nth power weighted objection function was adopted and three different derivation methods were demonstrated while the Schwartz inequality method was mainly demonstrated. The performance of the ETSGL-CFAL and the ETSGL guidance laws was compared through simulation. Simulation results show that although a first-order autopilot is introduced into the ETSGL-CFAL guidance system, the position miss distance and terminal impact angle error induced by the impact angle is zero for different guidance time.     

基于自抗扰技术的高超声速飞行器控制系统设计

高超声速飞行器在飞行过程中超燃冲压发动机对攻角及侧滑角有较严格的要求,为实现对攻角及侧滑角的精确控制,文章采用自抗扰控制技术设计了高超声速飞行器的攻角自动驾驶仪;首先建立高超声速飞行器控制系统的数学模型,然后采用扩张状态观测器对受扰对象的状态和干扰进行观测,并对状态误差采用非线性反馈,对观测的干扰进行补偿,从而实现对干扰的快速抑制和对指令的精确跟踪,最后仿真表明所设计的自动驾驶仪满足性能要求,验证了该方法的正确性。     

自动驾驶仪信号源仿真设备的软件开发

针对自动驾驶仪系统信号源仿真设备软件的可靠性问题,采用软件工程化开发方法,分析软件需求、软件设计重点和软件开发过程中的关键问题。应用结果证明,驾驶仪信号源仿真设备的软件质量较好,可仿真与驾驶仪交联的传感器分系统和电子飞行仪表系统的数字信号,为驾驶仪提供良好的闭环仿真试验环境和软件测评环境。     

小型无人机自动驾驶仪控制系统的研究

自动驾驶仪是无人机飞行控制系统的核心装置。本文设计的自动驾驶仪采用了两个处理器,且导航控制系统与姿态控制系统控制是分开的。它不仅具有高精度、高效率的性能,同时还具有通用性。文中对所设计的自动驾驶仪的结构和主要部件进行了介绍,同时着重分析了自主飞行模块。最后对飞行姿态进行仿真分析,仿真结果表明该系统满足性能要求。     

Observer-based Guidance Law Accounting for Second-order Dynamics of Missile Autopilots

Accounting for the missile autopilot as second-order dynamics, an observer-based guidance law is designed based on the dynamic surface control method. Some first-order low-pass filters are introduced into the design process to avoid the occurrence of high-order derivatives of the line of sight angle in the expression of guidance law such that it can be implemented in practical applications. The proposed guidance law is effective in compensating the bad influence of the autopilot lag on guidance accuracy. In the simulations of intercepting non maneuvering targets, targets with step acceleration, and targets with sinusoidal acceleration respectively, the guidance law is compared with the adaptive sliding mode guidance law in the presence of missile autopilot lag. The simulation results show that the proposed guidance law is able to guide a missile to accurately intercept a maneuvering target, even if it escapes in a great and fast maneuver and the autopilot has a relatively large lag.     

Model reference adaptive robust fuzzy control for ship steering autopilot with uncertain nonlinear systems

A novel model reference adaptive robust fuzzy control algorithm is presented for ship steering autopilot, which is an uncertain nonlinear system. In the proposed algorithm, fuzzy logic systems have been used to approximate lumped unknown function in the ship steering systems and the adaptive mechanism with minimal learning parameter, i.e. only one parameter, has been achieved by use of Lyapunov approach. The proposed methodology is verified using the simulation mode of the Dalian Maritime University's ocean-going training ship named Yulong. It is shown that the proposed algorithm guarantees that the ship steering autopilot system is asymptotically stable and its tracking error can approach to zero.     

Application of real/mixed μ computational techniques to an H∞ missile autopilot

A multivariable missile autopilot is synthesized using an H_∞ approach. A tradeoff is achieved between performance, actuators solicitation and uncertainties in the actuators and bending modes dynamics. Robust stability and performance of the control law are then studied in the face of large real parametric aerodynamic uncertainties: computational techniques for real and mixed μ analysis (namely De Gaston and Safonov's, Dailey's, Jones’, Young and Doyle's, Fan, Tits and Doyle's and Safonov and Lee's methods) are briefly reviewed before being used to compute either the exact value, or an interval of the structured singular value (SSV). For small amounts of parameters, the upper and lower bounds provided by these methods are compared to the exact value, computed by De Gaston and Safonov's method. For larger amounts of parameters, NP hardness of the problem prohibits the use of algorithms which compute the exact value: these algorithms are indeed necessarily exponential-time. As an alternative in this case, the use of polynomial-time methods for computing upper and lower bounds leads in our examples to accurate approximates of the real and mixed structured singular values.     

离散变结构控制及在船舶舵机中的应用

研究离散时间系统的变结构控制设计问题,提供了一种新方法。首先,提出一种具有原点稳定性的趋近律,可以消除传统离散趋近律自身参数导致的抖振;其次,研究了一种不确定性估计算法,可使估计误差动态与滑模动态解耦,只要不确定性变化率有界,即可保证闭环系统的鲁棒稳定性,不会产生抖振。将所提方法用于船舶自动舵系统的控制,仿真结果表明,无论是否存在不确定性,所设计的控制器均可快速、准确地跟踪设定航向。     

自动驾驶仪神经网络控制的HLA仿真研究

在对空空导弹自动驾驶仪各功能模块需求和能力分析的基础上,以组件的重用和可扩展为目标,运用HLA技术划分各联邦成员,成功组建神经网络自动驾驶仪分布式仿真系统。设计过程中的关键技术如对FOM/SOM设计和Simulink模型代码转换分别做了研究,给出了基于Matlab/Simulink所建立的空空导弹自动驾驶仪神经网络控制算法与HLA集成的一个工程样例。