高超声速飞行器姿态控制系统设计

研究气动特性是飞行器姿态稳定性的保证,高超声速飞行器采用姿态控制有助于提高作战效能及生存能力.针对高超声速飞行器作战环境复杂,大气密度偏差大、力/力矩系数不准确造成气动参数偏差较大等特点,采用参数空间方法来设计姿态控制系统.首先建立适用于姿态控制系统的高超声速数学模型,在高超声速气动特性条件下,提出三回路姿态稳定控制系统,根据参数空间方法的原理设计出各回路控制器,最后进行仿真分析验证控制系统的性能.仿真结果表明当气动参数存在较大偏差时,采用基于参数空间法设计的高超声速姿态控制系统可以确保对指令的精确跟踪,并且具有较强的鲁棒稳定性.     

基于INA—QFT的高超声速飞行器鲁棒控制器设计

针对高超声速飞行器数学模型的不确定性,提出基于逆奈氏阵列法设计预补偿器和定量反馈理论设计控制器相结合的方法。该方法首先对相互关联的飞行器三通道进行预补偿,使开环前向通道的逆传递函数矩阵成为对角优势阵。然后根据某型号飞行器俯仰通道多个模型参数变化范围,利用定量反馈理论进行鲁棒控制器设计。线性和非线性仿真结果表明,该方法跟踪效果良好,具有较强的工程应用价值。     

航空布撒器倾斜转弯自动驾驶仪设计与仿真

航空布撒器动力学具有非线性、强耦合、大参变的特点.针对动力学模型耦合和气动系数不确定性,给出了倾斜转弯自动驾驶仪的三通道独立设计方法.首先,采用混合灵敏度理论设计俯仰和滚转通道自动驾驶仪,以保证弹体在大空域范围内有较好的指令响应特性和稳定性.针对快速滚转引起的耦合,在偏航通道中引入攻角和滚转角速率信息,实现滚转/偏航运动解耦,抑制侧滑角.全弹道仿真表明,该方法设计的驾驶仪能适应大范围的气动参数变化,具有很好的鲁棒性,并能有效地实现倾斜转弯控制的好r forl coordinated law for yaw channel is givenaft Using .     

高超声速飞行器非线性鲁棒控制律设计

高超声速飞行器具有模型非线性程度高、耦合程度强、参数不确定性大、抗干扰能力弱等特点,其自主控制具有较大的挑战.论文提出了一种基于鲁棒补偿技术和反馈线性化方法的非线性鲁棒控制方法.文中首先采用反馈线性化的方法对纵向模型进行输入输出线性化,实现速度和高度通道的解耦和非线性模型的线性化.针对得到的线性模型,设计包括标称控制器和鲁棒补偿器的线性控制器.基于极点配置原理,设计标称控制器使标称线性系统具有期望的输入输出特性,利用鲁棒补偿器来抑制参数不确定性和外界扰动对于闭环控制系统的影响.基于小增益定理,证明了闭环控制系统的鲁棒稳定性和鲁棒跟踪性能.相比于非线性回路成形控制方法,仿真结果表明了所设计非线性鲁棒控制算法的有效性和优越性.     

高超声速飞行器动力学建模与分析

吸气式高超声速飞行器本身具有复杂动力学特性,由于存在强烈的结构弹性/推力/气动的耦合以及其力学环境的诸多不确定因素,使得飞行器本身的动态特性相当复杂.经典牛顿力学方法建模难以清楚反映飞行器结构弹性/推力/气动耦合.为更为精确的分析高超声速飞行器复杂的动力学特性,本文针对吸气式高超声速飞行器采用拉格朗日法进行了建模与动态特性分析,选择了具有代表性的特征点,建立了小扰动模型,在不同特征点上采用拉格朗日模型和牛顿力学模型对比分析高超声速飞行器的动力学特性.结果表明,拉格朗日方法所建立的动力学模型能够更清楚地符合高超声速飞行器结构弹性和气动特性耦合以及发动机尾流和气动特性之间的耦合特性.     

BTT导弹横侧通道H∞鲁棒控制器设计研究

考虑到BTT导弹存在较大的耦合和不确定性,传统频域控制理论以及三通道独立设计方法不再适用于自动驾驶仪的设计.为此,研究了BTT导弹横侧通道H∞鲁棒控制器的设计问题,用以抑制不确定性、外来扰动以及通道间耦合给系统带来的不利影响.首先分析了H∞鲁棒控制器设计中存在的关键问题,包括不确定性的分析及加权函数的选择;然后通过建立包含未建模不确定的被控对象、引入加权函数,得到了扩展的广义受控系统,利用Matlab鲁棒控制工具箱设计了BTT导弹横侧通道的H∞鲁棒控制器;最后通过仿真验证,表明设计的H∞鲁棒控制器具有良好的控制性能和鲁棒性.     

具有非线性不确定性的高超声速飞行器的 分布式鲁棒反步跟踪控制

本文针对具有外部干扰,参数摄动和非连续未知非线性气动影响的一般高超声速飞行器纵向动力学问题,设计了分布式鲁棒反步跟踪控制器.为了处理复杂的系统,将标准反步控制和信号补偿方法结合起来构成一个"简单"的鲁棒控制器.该方法不仅可以保证闭环系统半全局鲁棒跟踪性能,也可保证系统跟踪误差以期望的收敛速度收敛到期望的误差范围内.最后,带有非线性不确定性,外部干扰和参数扰动的仿真系统说明了该方法的有效性.     

具有非线性不确定性的高超声速飞行器的分布式鲁棒反步跟踪控制（英文）

本文针对具有外部干扰,参数摄动和非连续未知非线性气动影响的一般高超声速飞行器纵向动力学问题,设计了分布式鲁棒反步跟踪控制器.为了处理复杂的系统,将标准反步控制和信号补偿方法结合起来构成一个"简单"的鲁棒控制器.该方法不仅可以保证闭环系统半全局鲁棒跟踪性能,也可保证系统跟踪误差以期望的收敛速度收敛到期望的误差范围内.最后,带有非线性不确定性,外部干扰和参数扰动的仿真系统说明了该方法的有效性.     

高超声速飞行器模型参考变结构自动驾驶仪设计

与传统飞行器相比,高超声速的高度一体化设计造成空气动力学、推进系统和结构动态严重耦合,导致其对飞行条件的变化极其敏感,并且使得气动特性难以准确分析,这些都给其飞行控制系统设计带来了极大的挑战;文章引入了一种能够抵抗参数大范围变化的控制方法一模型参考变结构控制(MRVSC)对飞行器俯仰通道自动驾驶仪进行设计,并应用MATLAB分别对PID控制和MRVSC两种方法进行仿真分析;仿真结果表明,和经典控制方式相比,MRVSC能够更好地抵抗参数扰动影响,具有很好的控制效果.     

面向控制的弹性体高超声速飞行器建模与分析

针对高超声速飞行器建模中气动-推进-弹性结构之间的耦合问题, 给出飞行器综合建模方法. 利用空气动力学相关理论估算气动力、推力及弹性模态, 建立了高超声速飞行器弹性体机理模型和面向控制模型, 分析了气动加热和质量变化对飞行器弹性模态的影响及纵向气动特性. 实验结果表明, 气动加热和质量变化对弹性模态影响显著, 面向控制模型能降低模型的复杂度, 保留机理模型的耦合特性, 并为控制器设计提供模型依据.

     

基于变结构理论的高超音速飞机纵向逆飞行控制

针对高超音速飞机模型的高度非线性、强耦合、参数不确定等特点，提出了基于变结构理论的动态逆控制方法．该方法将逆控制的非线性解耦能力与变结构理论的强鲁棒性能有机结合，确保了高超音速飞机飞行的纵向稳定性，改善了其控制性能．仿真研究表明该控制方法对于高超音速飞机是可行的．     

基于随机鲁棒设计的高超音速飞行器线性二次型控制

针对高超音速飞行器具有高度非线性、输入输出之间强耦合以及参数不确定等特点,提出了基于随机鲁棒设计的线性二次型控制。这一控制方案基于系统控制需求,利用蒙特卡罗仿真方法建立随机鲁棒目标函数,并通过遗传算法优化控制系统设计参数。该控制方案保证了飞行的纵向稳定性,改善了其控制性能。基于某常规高超音速飞行器纵向模型进行仿真验证,结果表明该方案能够满足系统控制需求且具有强鲁棒性。     

小型自治水下机器人控制系统研究开发

开发了一种性价比高的CAN总线分布式自治水下机器人控制系统结构,并采用了独特的故障处理方法．根据弱耦合简化模型,详细设计了航行控制器,并对航行控制系统进行了仿真研究．仿真与试验结果表明: 控制系统性能可靠、传输率高,并具有很好的鲁棒性与稳定性,能够满足水下机器人工作环境复杂多变的要求．     

A robust and high precision optimal explicit guidance scheme for solid motor propelled launch vehicles with thrust and drag uncertainty

A new nonlinear optimal and explicit guidance law is presented in this paper for launch vehicles propelled by solid motors. It can ensure very high terminal precision despite not having the exact knowledge of the thrust–time curve apriori. This was motivated from using it for a carrier launch vehicle in a hypersonic mission, which demands an extremely narrow terminal accuracy window for the launch vehicle for successful initiation of operation of the hypersonic vehicle. The proposed explicit guidance scheme, which computes the optimal guidance command online, ensures the required stringent final conditions with high precision at the injection point. A key feature of the proposed guidance law is an innovative extension of the recently developed model predictive static programming guidance with flexible final time. A penalty function approach is also followed to meet the input and output inequality constraints throughout the vehicle trajectory. In this paper, the guidance law has been successfully validated from nonlinear six degree-of-freedom simulation studies by designing an inner-loop autopilot as well, which enhances confidence of its usefulness significantly. In addition to excellent nominal results, the proposed guidance has been found to have good robustness for perturbed cases as well.     

基于模糊控制的高超声速飞行器二阶滑模姿态控制

考虑高超声速飞行器飞行过程中气动参数变动导致的不确定,将模糊控制与二阶滑模控制相结合,形成自适应模糊二阶滑模控制器,用于控制高超声速飞行器姿态的飞行系统中.依据奇异摄动理论,设计快速和慢速双闭环系统控制角速率和姿态角.设计二阶滑模控制器用于有效地衰减抖振,同时对姿态角指令实现准确和快速跟踪.采用自适应模糊逻辑逼近高超声速飞行器动力学和运动学模型中的不确定部分,以对控制器进行有效补偿,基于Lyapunov稳定性理论,推导模糊规则参数的自适应律,确保整个闭环控制系统的稳定.仿真结果表明,所提出的高超声速飞行器的自适应模糊滑模控制系统能够有效抑制气动参数摄动的影响,对姿态角指令有较好的跟踪性能.     

带有干扰观测器的高超声速飞行器滑模控制

针对高超声速飞行器非线性和易受干扰影响的特点,提出了带有扩张状态干扰观测器的连续滑模控制方法.在对飞行器非线性模型做线性化处理的基础上,设计了一种连续时间滑模控制器.该控制器在对不确定性和未知动态保持鲁棒性的基础上,消除了传统滑模中存在的抖振现象.对系统中存在的外加干扰,设计了扩张状态干扰观测器.将外加干扰作为系统的一个状态变量被估计出来,再将估计值用作滑模控制器的补偿量,进而达到消除外干扰的目的.在高超声速飞行器巡航飞行状态的基础上进行了仿真.仿真结果表明,所提出的方案能够满足控制要求.     

A Novel Robust Flight Controller Design for an Air-Breathing Hypersonic Vehicle

A novel robust flight control design method is proposed for a generic air-breathing hypersonic vehicle based on a state-dependent Riccati equation technique and a nonlinear disturbance observer. The highly nonlinear dynamics of the hypersonic vehicle are firstly brought to a linear structure having a state-dependent coefficient form. And then a state-dependent Riccati equation is solved at each sampling moment to obtain a nonlinear feedback optimal control law. In order to enhance robustness of the closed-loop system, a nonlinear disturbance observer is introduced to estimate the uncertainty caused by parametric variations and external disturbances. The resulting composite controller achieves not only promising robustness and disturbance rejection performance but also flexible adjustment in the response time. Compared to a Kriging controller, the proposed controller has great advantages in the system response time and robustness. The feasibility of the proposed method is validated by simulation results.     

Adaptive‐gain multivariable super‐twisting sliding mode control for reentry RLV with torque perturbation

Reusable launch vehicle (RLV) should be under control in the presence of model uncertainty and external disturbance, which is considered as torque perturbation in this paper during the reentry phase. Such a challenge imposes tight requirements to the enhanced robustness and accuracy of the vehicle autopilot. The key of this paper is to propose an adaptive‐gain multivariable super‐twisting sliding mode controller when considering that the bounds of uncertainty and perturbation are not known. The important features of the controller are that the adaptation algorithm can achieve non‐overestimating values of the control gains and the multivariable super‐twisting sliding mode approach can obtain a more elegant solution in finite time. According to the multiple‐time scale features, the dynamics of RLV attitude motion are divided into outer‐loop subsystem and inner‐loop subsystem. On this basis, the controllers are designed respectively to ensure the finite‐time reentry attitude tracking. In addition, a proof of the finite‐time convergence for the overall system is derived using the Lyapunov function technique and multiple‐time scale characteristic. Finally, simulation results of six degree‐of‐freedom RLV are provided to verify the effectiveness and robustness of the proposed controller in tracking the guidance commands as well as achieving a safe and stable reentry flight. Copyright © 2016 John Wiley & Sons, Ltd.     

Reentry attitude tracking via coupling effect-triggered control subjected to bounded uncertainties

The attitude tracking control issue for hypersonic reentry vehicle subjected to bounded uncertainties is investigated in this paper. The uncertainties are estimated by a disturbance observer with a simple structure whose parameter tuning methodology is provided to guarantee the system robustness. The coupling effect of the hypersonic reentry vehicle is analysed with a binary form based on a coupling effect indicator. The positive or negative value of indicator represents the harmful or beneficial coupling effect on the system. Then, a coupling effect-triggered control is developed to cancel the harmful couplings while utilising the beneficial couplings. The trigger point in the controller occurs when the property of the coupling effect happens to change. The specific criterion is introduced to quantify the performance improvement via the proposed scheme. Application to the hypersonic reentry tracking is presented to demonstrate the validity of the proposed method.     

The design of suboptimal asymptotic stabilising controllers for nonlinear slowly varying systems

The design of asymptotic stabilising controllers for slowly varying nonlinear systems is considered in this paper. The designed control law is based on finding a slowly varying control Lyapunov function. Also, consideration of the Hamilton–Jacobi–Bellman equation showed that the proposed controller is a suboptimal controller and the response of the system may be very close to its optimal solution. The maximum admissible rate of changes of the system dynamic is also evaluated. This technique is first applied to a created example and then to a practical example (optimal autopilot design for an air vehicle). The air vehicle is modelled as a nonlinear slowly varying system and the efficiency of the designed autopilot in terms of transient responses, control signals and the values of cost function are shown by numerical simulations.