This paper proposes a method for estimating air data, including angle of attack (AoA), angle of sideslip (AoSS), Mach number, and static pressure, by integrating Flush Air Data Sensing (FADS), Inertial Navigation System (INS), and weather forecast data. The method applies to subsonic, transonic, supersonic, and hypersonic flight, supporting real-time and post-flight data processing. A filtering equation is developed using the FADS pressure model and flight kinematics, incorporating INS states and FADS measurements. The Cubature Kalman Filter (CKF) is used to fuse the data and estimate airspeed and ground speed, which are then converted into air data. Numerical simulations show that incorporating weather forecast information significantly reduces errors, with CKF outperforming the Extended Kalman Filter (EKF) in accuracy.

对飞行器大气数据进行估计是获取飞行状态的重要一环,是实现飞行器控制和稳定飞行的基础.通过研究嵌入式大气数据传感(FADS)系统,提出了基于容积卡尔曼滤波的惯性测量元件(IMU)数据和FADS数据融合算法.该算法对飞行器运动状态建立高阶滤波模型,使用容积点加权求和逼近的方法估计非线性运动模型,滤波输出值经处理后得到马赫数、攻角、侧滑角等大气数据.经仿真实验,算法计算的大气数据较为准确,马赫数误差小于0.01,攻角和侧滑角的误差小于0.1°.

In this paper, the design and validation of an air data system algorithm for estimating the angle of attack and sideslip are presented. To reduce estimation error and improve system performance, the algorithm should deliver accurate output. The method uses a flush air data sensing system (FADS) model composed of aircraft surface air pressure and an inertial navigation system (INS) model within an unscented Kalman filter (UKF) framework. UKF uses inertial system measurements of Euler angles, body rates, body accelerations, and a measurement of dynamic pressure to form estimates. After simulations and comparison of results, this technique reduces errors in aircraft estimates of air data and improves survivability as well as reliability.

针对嵌入式大气数据传感(FADS)系统与惯性导航系统(INS)组合滤波计算攻角/侧滑角时,机动飞行和平飞时对滤波常数的大小需求不一致的问题,提出一种滤波常数能够随着飞行状态自适应调整的变增益互补滤波算法.算法可以随着飞行状态的变化,改变滤波常数τ,保持整个飞行阶段具有更好的攻角融合结果,以提高角度的估计精度.同时将测压孔分组计算攻角,对攻角的延迟进行检测,若延迟过大,则判定为该组攻角失效.仿真结果表明:提出的滤波算法能保持整个飞行阶段内的攻角/侧滑角估计结果误差不超过0.2°,并且相比于固定增益互补滤波器,变增益互补滤波的估计误差更小.

针对飞行器在高速飞行时受气流干扰、惯性数据易发散等问题,从传感器数据融合角度出发,提出了通过无迹卡尔曼滤波(UKF)融合嵌入式大气数据观测系统(FADS)和惯性导航系统(INS)估计飞行器实时大气数据的算法.算法使用高维度非线性方程对惯性系统和大气系统间的关系建模,结合FADS与INS的数据,计算飞行器速度和高度,进而估算出攻角、侧滑角等参数.实验结果显示,与INS直接解算、扩展卡尔曼滤波(EKF)融合等原有估计方法相比,文章所述的算法在估计精度和系统稳定性方面均有所提高.

Aiming to the complex operation condition and strong coupling dynamic characteristics of hypersonic vehicles, this paper develops a parametric model which is suitable to the control integrated design. First, the necessities and research status of the control integrated design of hypersonic vehicles are discussed. Then, the typical hypersonic waverider shape is geometrically parametrized using the quadratic curve and class/shape function methods. After that, the forces and moments of the hypersonic vehicle are estimated based on the surface element method in combination with the engineering estimation formulas, and the nonlinear dynamic parametrization model is built. Furthermore, the analytical expressions of forces and moments are obtained by means of the sensitive analysis strategies as a result that the complicated nonlinear dynamics model is changed to the iterative design model. Finally, an illustrative example is provided to verify the feasibility of this proposed method, and the according results show that the developed parametrization model enables to meet the requirements of the control integrated design.

For the air-breathing hypersonic vehicles (AHSV) with a broad flight envelope, this paper proposes a new controller design method to ensure robust stability in the presence of external disturbances. The proposed method is based on the guardian maps theory and H∞ Linear Parameter Varying (LPV) technique. In this paper, an LPV model of the AHSV is firstly established using the Jacobian linearization method. By incorporating the guardian maps theory and H∞ technique, a set of controllers is designed such that the closed loop poles lie in the desired area. The major merit of the proposed method is that all controller parameters over the overall flight envelope can be automatically determined in the iterative courses that are started from an arbitrary initial point within the flight envelope. Finally, the proposed approach is demonstrated by an illustrative example. The results show that the designed controller is operated to stabilize the air-breathing hypersonic vehicle over a wide flight envelope, and to exhibit satisfactory tracking performance as well as strong robustness.

This paper presents a trade-off design scheme with consideration of the pressure-tap configuration and solving model for a Flush Air Data Sensing System (FADS). First, a mechanism model of FADS is built for the basic structure in order to transform the measured pressures to the required air data. Then, several iteration algorithms are introduced for FADS to obtain the converging results of the solving model. Furthermore, four kinds of the pressure-tap configurations are designed in the relation to the basic structure, and the issues on the iteration convergence and modeling errors are discussed to analyze the compromise relations between the pressure-tap configuration and solving model. Lastly, a simulation example is applied to verify the feasibility of this proposed scheme, and at the same time some suggestions in the real application are provided for FADS. (C) 2016 Elsevier Ltd. All rights reserved.

Abstract This paper presents the geometric modeling methods based on the class and shape function transformation (CST) technique for the hypersonic vehicle. First, the typical waverider configuration is considered to be the basic shape for the hypersonic vehicle, and then the CST method is applied to describe and build the improved geometric shape. On this basis, the aerodynamic forces and thrust are estimated according to the shock wave and Rayleigh flow theory. Furthermore, the model dynamic features using the CST method are analyzed in comparison to the basic shape. Finally, the simulation results show the effectiveness of this method for the hypersonic vehicle.

In the light of the broad range of hypersonic flight conditions, a design method of switching control based on guardian maps is proposed to guarantee the global stability within the flight envelope. First, a linear parameter varying (LPV) model of a hypersonic vehicle is established over a range of hypersonic flight conditions. The parameters of controller are determined by pole placement technology with the target pole locations at the boundaries of the parameters variation range. Second, a new range of flight conditions that ensures system stability with current controller is analyzed based on guardian maps. The execution of the iterative process is used to determinate the set of controller parameters overall the flight envelope with initial target pole locations. By switching controller parameters the closed-loop performance is guaranteed over the entire flight envelope. The simulation shows that the proposed design method has the ability to ensure the global stability over the flight envelope, and achieving good tracking performance.

Compared with traditional vehicles, the dynamic model of hypersonic vehicles features higher nonlinearity, tighter coupling and stronger uncertainty. What's more, the designed controller needs to have more stringent performance demands as well as robustness requirements. According to the guardian maps theory, a proposed design method can adaptively adjust control parameters in relation to the given control structure for hypersonic vehicles. First, a linear parameter varying (LPV) model of a hypersonic vehicle is established, and after that handling qualities are translated in terms of eigenvalue confinement. Then for a fixed controller architecture and initial controller gains, a set of control parameters is adjusted automatically using this theory while ensuring generalized stability in the expected flight process. Finally, an example of a hypersonic vehicle is provided in simulation to verify the feasibility of the proposed control method.

为在高超声速飞行器设计初期快速地获得推力和推力矩,以满足控制相关分析和建模需要.提出一种推进系统建模方法,基于激波/膨胀波相交理论来建模与机身耦合的进气道模型;用有摩擦变截面加热管来描述双模态燃烧室;将内喷管建模成一维变截面摩擦管,采用动量定理估算推力,并通过曲线拟合得到推力的解析表达式.与CFD计算结果相比,该模型计算得到双模态冲压发动机入口气流马赫数和温度误差小于5％,压强误差小于10％;计算得到的推力随马赫数、燃油当量比和迎角的增大而增加,随高度增加而减小,单个状态平均计算时间小于0.5s.计算结果表明:该建模方法满足面向控制建模的效率和精度需求,有助于此类飞行器设计初期的动力学和控制相关的分析和设计.

针对高超声速飞行器模型具有高度非线性和易变的动态特性,应用保护映射理论提出了一种高超声速飞行器大包线控制律设计方法.首先,结合间隙度量理论建立高超声速飞行器线性变参数(linear parameter-varying,LPV)模型,然后设计控制器结构并计算初始点的控制器参数,并根据保护映射理论分析初始控制器使闭环系统稳定的参数区间,通过迭代运算自适应地获得满足性能要求的控制器参数集合.仿真结果表明,建立的LPV模型具有良好的精确度;所设计的大包线控制律能够满足高超声速飞行器的性能要求,并且保证系统在飞行域内全局稳定.

针对高超声速飞行器包线范围广、参数变化大的控制需求,应用保护映射理论提出一种高超声速飞行器的自适应控制律设计方法.首先建立整个飞行包线内的线性变参数(LPV)模型,在参数变化边界点设计一个初始的控制结构和参数,然后基于保护映射理论分析初始控制结构使闭环系统稳定的参数范围,通过迭代自动获取整个包线内满足性能指标的控制参数,进而通过多项式拟合设计出高超声速飞行器自适应控制律.所提出的方法能够根据初始控制结构自动寻找一系列满足性能要求的控制器参数,并确定这些控制参数满足闭环系统稳定的设计范围.仿真结果表明,所设计的自适应控制律能够确保高超声速飞行器大包线的设计要求,实现闭环系统的鲁棒稳定.

Powerful actuators are both indispensable and critical components for the flight control system of hypersonic vehicles. More importantly, the performance of actuators has substantial impact on the control ability; therefore, when designing the control system, one needs to fully take into account actuator restraints in order to meet the efficient and precise control demands under complex flight conditions. In this article, the advanced flight control methods concerned with actuator limitations are discussed for hypersonic vehicles. First, the longitudinal model of hypersonic vehicle is established with consideration of the nonlinear coupling dynamics. Second, the actuator constraints with the effect of elastic deformation are introduced to this built model and then the resulting unstable dynamics characteristic and the control limitation conditions are analyzed for hypersonic vehicle. Furthermore, the advanced flight control laws are designed by using the differential geometry principle and the total energy theory. Finally, simulation results verify the feasibility of the proposed methods for hypersonic vehicle.

The design problems using multidisciplinary parameterization methods for a hypersonic morphing vehicle are investigated in this paper. First, the non-linear model of the hypersonic morphing vehicle in line with the parameterized process is established by combining with the different disciplines. Then, the waverider performances determined by the static and dynamic properties are discussed by application of the multidisciplinary design ideas. Afterwards, the optimal results considering the anticipated performance criteria are acquired by multidisciplinary optimization. Furthermore, the switching control system is designed for hypersonic morphing vehicle to implement the smooth morphing process and to guarantee the overall stability. Finally, the proposed methods are verified by a numerical example, and the resulting simulation shows that waveriding performance can be enhanced as the hypersonic vehicle is designed as a morphing shape.

With the development of high-performance aircraft, precise air data are necessary to complete challenging tasks such as flight maneuvering with large angles of attack and high speed. As a result, the flush air data sensing system (FADS) was developed to satisfy the stricter control demands. In this paper, comparative stuides on the solving model and algorithm for FADS are conducted. First, the basic principles of FADS are given to elucidate the nonlinear relations between the inputs and the outputs. Then, several different solving models and algorithms of FADS are provided to compute the air data, including the angle of attck, sideslip angle, dynamic pressure and static pressure. Afterwards, the evaluation criteria of the resulting models and algorithms are discussed to satisfy the real design demands. Futhermore, a simulation using these algorithms is performed to identify the properites of the distinct models and algorithms such as the measuring precision and real-time features. The advantages of these models and algorithms corresponding to the different flight conditions are also analyzed, furthermore, some suggestions on their engineering applications are proposed to help future research.

In order to obtain a class of reliable air-breathing hypersonic vehicle(AHSV), the paper provides system design optimization strategies for control relevant model based on its unique flight dynamic characteristics and the coupling with the control system. The first section briefly introduce the main issues and approaches for first principle modeling and parametric modeling of AHSV. The second part discusses the main coupled constraints between the model and control performance, and this model has unstable poles and their left eigenvectors, along with control saturation constraints determining the null-controllable region. In particular, RHP poles and zeros of this model limit the bandwidth and the H∞norm of the sensitivity function and the complementary sensitivity function. Based on coupling characteristics and the selection of overall optimization objective, the following work describes the plant and control system optimization strategies for the optimal design, witch provides a research methodology and design method for AHSV.

嵌入式大气数据传感(FADS)系统空气动力学模型基于钝头体推导,该模型适用于锥头体解算大气数据,但存在一定的模型误差.为消除模型误差,分析了锥头体模型误差产生的机理,提出了一种FADS系统组合算法,并对某一典型锥体弹头进行了仿真验证.仿真结果表明:动静压相对误差在0.05％以内,每组大气数据解算平均耗时在20 ms以内,该算法有效提高了大气数据解算精度和实时性.

嵌入式大气数据传感系统的空气动力学模型基于钝头体推导,该模型是否适用于锥头体尚未得到证实;对一典型锥头体进行了空气动力学模型适用性验证,验证结果表明该空气动力学模型用于锥头体时动静压相对误差超过了2.5%;对此,提出了一种适用于锥头体的改进校准算法,并且进行了仿真验证;仿真结果表明动静压相对误差小于0.5%,改进的校准算法有效消除了模型误差。