助推_滑翔式飞行器弹道优化仿真研究

研究助推_滑翔式飞行器弹道优化问题。对助推_滑翔式飞行器弹道进行优化有利于提高其综合飞行能力。为了增加助推_滑翔式飞行器射程,针对助推_滑翔式飞行器的弹道特点,在考虑攻角、法向过载及终端约束条件下,提出应用SWIFT(序贯加权因子)法进行弹道优化,并将优化结果与应用SQP(序列二次规划)算法优化所得到的结果进行对比仿真分析。仿真结果证明:SWIFT算法是一种解决助推_滑翔式飞行器弹道优化问题的有效方法,具有优化精度高,优化所需时间短的特点。     

临近空间高超声速滑翔机动GNC技术

临近空间飞行器利用临近空间独特的环境特点,采用升力体构型,基于助推滑翔式弹道,实现高超声速滑翔扣机动,极具发展潜力.介绍临近空间高超声速飞行器的发展历程,根据其飞行特点深入分析临近空间高超声速滑翔机动飞行所需的高精度GNC技术,并对其发展前景进行展望.     

助推——滑翔增程弹弹道优化

研究在给定射程条件下的火箭助推滑翔增程弹最短飞行时间弹道优化问题,为提高作战效能,提出建立纵向平面内弹道优化模型.最短时间弹道优化模型以射角、助推火箭点火时刻、滑翔攻角为优化变量,并考虑了优化变量的约束.以射程为自变量而不再以时间为自变量,以便采用序列二次规划法作为其优化算法.以某型火箭助推滑翔增程弹为对象进行数值仿真,结果表明,优化的滑翔攻角曲线平滑,滑翔弹道平直.在给定射程条件下最短飞行时间可作为实际作战中的方案弹道,实现对地面固定目标的快速打击,为弹道优化提供了依据.     

采用高抛弹道的反临拦截器制导律设计

高超声速武器拦截由于相对速度极快,机动能力、速度均不占优势,因此需要进行高精度的中、末制导研究。本文以临近空间高超声速巡航飞行器为拦截对象,提出了采用高抛弹道拦截的设计思路,针对临近空间飞行器的弹道特征和机动性能,设计高抛弹道的初、中、末复合制导律,并对目标进行不同机动模式的拦截效果进行分析,仿真结果表明,基于高抛弹道的拦截器能够有效拦截巡航类高超声速临近空间目标。     

折叠翼飞行器鲁棒飞行控制系统设计方法

为解决折叠翼飞行器在机载发射段主升力翼面/立尾展开前后气动特性变化较大,以及对飞行控制律鲁棒性要求较高的问题,基于飞行器六自由度非线性动态模型,应用随机鲁棒分析与设计方法(SRAD),对机载发射段折叠翼飞行器的翼面/立尾展开过程,设计了鲁棒飞行控制律,并通过对风干扰环境下的六自由度非线性弹道仿真,验证了翼面/立尾展开段鲁棒飞行控制律的有效性.     

折叠翼飞行器鲁棒飞行控制系统设计方法

为解决折叠翼飞行器在机载发射段主升力翼面/立尾展开前后气动特性变化较大,以及对飞行控制律鲁棒性要求较高的问题,基于飞行器六自由度非线性动态模型,应用随机鲁棒分析与设计方法(SRAD),对机载发射段折叠翼飞行器的翼面/立尾展开过程,设计了鲁棒飞行控制律,并通过对风干扰环境下的六自由度非线性弹道仿真,验证了翼面"立尾展开段鲁棒飞行控制律的有效性.

     

HGV平衡滑翔式轨迹可达区域计算方法研究

针对滑翔式高超声速飞行器(HGV)平衡滑翔轨迹可达区域的高精度快速计算问题,研究了一种基于降阶动力学模型和连续凸优化方法的可达区域计算方法。首先,根据“准平衡滑翔假设”条件,将再入飞行器三自由度动力学方程进行降阶处理,得到以速度为自变量的三阶动力学方程。然后,将可达区域计算问题描述为一系列满足再入走廊约束和初、末状态约束下的横程最大优化问题,将动力学方程进行线性化、离散化处理后,采用连续凸优化方法对该问题进行求解,得到了滑翔飞行器不同末端速度下的可达区域。最后,以CAV-H飞行器模型为例进行了仿真验证,结果表明,该方法具有较高的求解效率和可达区域计算精度。     

基于参数空间法的飞行器再入控制研究

针对空天飞行器再入段环境变化剧烈、气动参数变化范围大的特点,采用参数空间方法来设计其控制系统;首先建立飞行器控制系统的数学模型,鉴于飞行器再入过程中对攻角有着严格的要求,设计了以攻角反馈为被控信号的三回路自动驾驶仪结构,然后根据参数空间方法求出对应的控制器参数,最后基于Matlab/Simulink的非线性仿真表明,所设计的控制系统在大气密度偏差±30%、气动力/力矩系数各偏差±20%的组合偏差情况下仍具有较好的鲁棒稳定性和跟踪性能。     

类乘波飞行器弹道性能研究

火箭基循环发动机作为飞行器的推进系统,同时兼顾较大推重比和高比冲,将火箭基组合循环发动机和类乘波飞行器机身一体化,考察其对飞行器弹道性能的影响,具有深远意义.对类乘波飞行器飞行弹道分别建立大气模型、动力学模型、空气动力模型和推进模型,采用龙格-库塔法研究其弹道性能随时间的变化趋势,结果表明该飞行器在助推结束后消耗燃料少,占总质量的比重不超过5%,且助推结束后前50s速度和飞行航道倾角变化剧烈,随后变化渐趋平缓,利于控制,能够满足未来空天飞行器对安全性和可靠性的要求.     

光电编码器抗振动测速法在飞行器内弹道参数测量中的应用

针对水下发射飞行器内弹道参数测量的特殊性和复杂性,介绍一种基于拉线式测速器和光电编码器的抗振动测速方法.该方法将编码器的抗振动测速巧妙地应用到内弹道参数测量中,具有实现简单、精度高、易于安装和调试等特点,可满足多种冷发射的飞行器出筒速度测量的要求,具有较高的实用价值.     

DC‐to‐AC power conversion on a ‘boost’ converter

In this article, we provide an approximate sliding mode control‐based solution to the DC–AC power conversion problem on a ‘boost’ converter. The approach uses the flatness property of the system as a pivot for generating a sequence of minimum phase output reference trajectory candidates. The generated candidates are obtained as differential parameterizations of the minimum phase inductor current variable in terms of the non‐minimum phase desired output capacitor voltage. The associated residual dynamics of the ideal sliding motions is shown to reasonably approximate the desired biased sinusoidal output capacitor voltage signal. Copyright © 2001 John Wiley & Sons, Ltd.     

Robust flat filtering DSP based control of the boost converter

The article deals with the design and implementation of a flat filter tracking digital controller for a boost dc-dc power converter. A highly perturbed switched boost converter circuit is shown to be efficiently controlled, in a trajectory tracking task for its non-minimum phase output, by means of a suitable linear filter, here addressed as a flat filter. Flat filtering is a natural robust version of generalized proportional integral control (GPIC) by which the effects of arbitrary time varying exogenous disturbances, unknown endogenous nonlinearities and un-modeled dynamics can be jointly attenuated in a conceptually similar fashion to observer-based active disturbance rejection control (ADRC) and algebraic identification based model free control (MFC) but: a) without using extended state observers and b) respecting the original system order in a time-varying simplified model while avoiding algebraic estimation techniques. The proposed control technique based on the TMS320F28335 digital signal processor chip is tested by means of realistic simulations and experimental setup.     

VOLTAGE REGULATION OF A BUCK BOOST CONVERTER—A HYBRID CONTROL APPROACH

In this paper, the output voltage regulation problem in a buck boost converter is defined as a hybrid control problem. For control design, the mutually interacting continuous and discrete dynamics are modeled as a hybrid automaton. Thus, the control problem is defined as a guard selection problem of the hybrid automaton. The system trajectory is switched between different modes based on the guards to achieve the required voltage regulation. The guards defined are fixed surfaces represented in terms of the state variables for a given operating condition. The logic‐based switching in the state plane is stable in terms of the chaotic and bifurcation behavior. The effectiveness of the control scheme for buck and boost operation under line and load disturbances is demonstrated by simulation in the MATLAB‐SIMULINK environment and the results are presented.     

双足机器人自然ZMP轨迹生成方法研究

为了实现双足机器人类人行走,提出了一种基于自然ZMP轨迹的双足机器人步行模式生成方法。在单腿支撑相,根据基于三维线性倒立摆模型,在设定从脚跟到脚趾移动的自然ZMP轨迹后,得到质心轨迹方程;在双腿支撑相采用线性摆模型生成质心轨迹方程。同时给出了在统一坐标系中的多步规划质心轨迹方程。在RoboCup 3D仿真平台实现了采用自然ZMP轨迹的双足机器人类人稳定步行,实验和竞赛结果都验证了该方法的有效性。     

基于相平面轨迹特征的规则自调整模糊控制方法

通过对模糊控制系统相平面响应轨迹特性的分析, 提出了相平面响应轨迹实时特征向量和实时特征向量夹角的概念; 在分析实时特征向量夹角特性的基础上, 提出基于相平面响应轨迹特征的规则自调整模糊控制方法; 仿真结果表明, 该方法可以减小模糊控制系统的超调和过渡过程, 提高系统的收敛速度.     

Sliding mode control of boost and buck‐boost power converters using the dynamic sliding manifold

Non‐minimum phase tracking control is studied for boost and buck‐boost power converters. A sliding mode control algorithm is developed to track directly a causal voltage tracking profile given by an exogenous system. The approximate causal output non‐minimum phase asymptotic tracking in non‐linear boost and buck‐boost power converters is addressed via sliding mode control using a dynamic sliding manifold (DSM). Use of DSM allows the stabilization of the internal dynamics when the output tracking error tends asymptotically to zero in the sliding mode. The sliding mode controller with DSM links features of conventional sliding mode control (insensitivity to matched non‐linearities and disturbances) and a conventional dynamic compensator (accommodation to unmatched disturbances). Numerical examples demonstrate the effectiveness of the sliding mode controller even for a known time‐varying load. Copyright © 2003 John Wiley & Sons, Ltd.     

垂直/短距起降飞机的轨迹跟踪控制器设计

针对垂直/短距起降飞行器在悬停状态下滚转力矩与横侧向推力存在强耦合、系统具有非最小相位特性的问题,本文设计了轨迹跟踪控制器.首先利用坐标变换和输入输出线性化将系统分解成最小相位子系统和非最小相位子系统.对非最小相位子系统,采用稳态系统中心的方法求解理想内部动态,并跟踪系统理想内模设计了LQR控制器,使得内部动态有界;对最小相位子系统设计了高增益控制器使得外部动态渐进稳定.仿真结果表明本文设计的控制器对给定轨迹和飞行器机动轨迹都有较好的跟踪效果,验证了控制器的有效性.     

Fuzzy control design for the trajectory tracking in phase plane

Based on the concept of sliding mode control, the paper designs a fuzzy logic control for a linear system to achieve the trajectory tracking in the phase plane. That is, the system's state (e, e˙) is controlled to track the prespecified trajectory which is composed of several nonisoclinal segments. Each segment of the prespecified trajectory denotes the relation between the tracking error e and the error change e˙ in the corresponding region of the phase plane. In the paper, the prespecified trajectory is regarded as a sliding surface. A direct piecewise linear output formulation of the fuzzy logic controller is synthesized to achieve the hitting motion such that the trajectory tracking is completed region by region. We summarize the above analysis to be a fuzzy logic control design algorithm and give a practical example to illustrate its applicability     

运载火箭的距离惯性制导

本文应用系统辨识和参数估计理论,提出了运载火箭的主动段距离惯性制导系统.系统的精度比现有惯性制导系统的精度有较大的提高.另外,这种技术还可推广到运载火箭的精度鉴定和精确的落点预报.     

Tuning of evolutionary particle filtering approach for estimation of trajectory deviation

An autonomous vehicle launched from moving platform is subjected to flexure‐like disturbance and needs to stabilize itself before embarking on the target tracking phase. Control and guidance remains inactive during stabilization phase. Hence, estimating the deviation from the intended trajectory is important in the absence of control and guidance commands for trajectory correction. This estimation problem is here mapped to the misalignment estimation problem, with the intended trajectory data resembling mother data and the followed trajectory data resembling daughter data. The main requirement is fast convergence for early commencement of target tracking phase. Kalman filter and its variants fail to converge due to the inability to model time varying nonlinearities and flexure in the system model. Conventional particle filter converges, but computation time is high. This work explores evolutionary particle filter variants that may provide faster convergence through adaptive tuning of the range from where particle support points are selected. Such heuristics is based on the observed residual trend. Monte Carlo simulation results underline the importance of designing estimator based on adaptive tuned evolutionary particle filter algorithm.