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The major challenge of current strapdown inertial navigation system/celestial navigation system (SINS/RCNS) is failing to calibrate all the error coefficients of gyro and star sensor in-flight accurately, which will lead to the attitude accuracy degradation. To address this question, this paper proposes an optimal calibration method based on observability analysis. Here, we derive the star sensor measurement model with respect to initial alignment errors, gyro errors, and star sensor installation errors. And the observability analysis is employed to explain the reason why all the error coefficients can be estimated effectively by three maneuvers merely. Finally, the optimal observation sequence is determined based on the fisher information matrix (FIM). The proposed optimal calibration method is evaluated by a representative suborbital flight vehicle trajectory, which represents significant improvements in estimation accuracy of error coefficients, and realizes the attitude accuracy enhancements.

Aiming at the attitude control of a class of hypersonic morphing vehicles (HMVs) with variable sweep wings, a model-free adaptive dynamic planning (MFADP) optimal control method based on data-driven and finite-time fuzzy disturbance observer is proposed in this article. An integrated oriented-control attitude-morphing model is established, and morphing is considered as the state to carry out the integrated coupling attitude control. The control scheme is organized by a steady-feedback-compensation framework. To overcome the dependence on the unknown dynamic knowledge of HMVs, the dynamic model is reconstructed using neural networks for steady-state control. Subsequently, based on the MFADP algorithm, an Off–On serial policy learning strategy is designed for the error model to obtain a real-time approximate optimal feedback control. Additionally, a fuzzy disturbance observer with finite-time convergence ability is proposed to estimate and compensate the multiple uncertainties. Finally, the stability of the closed-loop system is proved theoretically and the simulation results demonstrate the improved performance of the proposed method.

This work focuses on the attitude control problem for hypersonic morphing vehicles (HMVs) with uncertainties. A span-morphing HMV model is first established with lumped disturbances. Based on fixed-time technique, a disturbance observer with fuzzy logic system (FLS) is proposed to enhance the robustness by estimating the unmodeled dynamics and external disturbances in fixed settling time. The multivariable fixed-time sliding mode manifold is applied to the transformed control system, which guarantees a direct control input design from attitude command and decent tracking performance. Then, the control system degenerates into an autonomous system, and the closed-loop fixed-time stability is ensured via Lyapunov synthesis and homogeneity theory. Finally, simulation results are presented to demonstrate the effectiveness of the proposed control scheme.

An autonomous optimal trajectory planning method based on the deep deterministic policy gradient (DDPG) algorithm of reinforcement learning (RL) for hypersonic vehicles (HV) is proposed in this paper. First, the trajectory planning problem is converted into a Markov Decision Process (MDP), and the amplitude of the bank angle is designated as the control input. The reward function of the MDP is set to minimize the trajectory terminal position errors with satisfying hard constraints. The deep neural network (DNN) is used to approximate the policy function and action-value function in the DDPG framework. The Actor network then computes the control input directly according to flight states. Using a limited exploration strategy, the optimal policy network would be considered fully trained when the reward value reached maximum convergence. Simulation results show that the policy network trained using a DDPG algorithm accomplishes 3-dimensional (3D) trajectory planning during the HV glide phase with high terminal precision and stable convergence. Additionally, the single step calculation time of the policy network occurs in near real time, which suggests great potential as an autonomous online trajectory planner. Monte Carlo experiments prove the strong robustness of the implementation of an autonomous trajectory planner under aerodynamic disturbances.

Whole‐crop wheat (Triticum aestivum) has high nutritive value, and it has become one of the main sources of roughage for ruminants in some countries or regions. This study investigates the effects of no tillage on nitrogen compounds and protease activities of whole‐crop wheat silage. Wheat was planted on the 9th day (NB9) and 5th day (NB5) before rice harvest and on the first day after rice harvest. Sowing before harvest involved no tillage and sowing after rice harvest involved either no tillage (NA1) or conventional tillage (CK). Compared to CK, the crude protein content of NB9 and NB5 decreased by 16.4% and 9.58%, respectively. With the delay of the sowing date, the contents of non‐protein nitrogen, rapidly degraded protein, and slowly degraded protein in whole‐plant wheat tended to increase. Compared to NA1 wheat silage, the NH3‐N content of NB9 and NB5 silages decreased by 52.7% and 34.4%, respectively. The acid protease activity of NA1 was significantly higher than that of other treatments (p< 0.05). There was no significant difference in the degree of protein degradation between NA1 and CK silages. Although the degree of protein degradation in early sowing was low, the degree of fermentation was also weak. Flowchart of measurement of nitrogen compounds and protease activities of silages.

With the increasing demands for high-accuracy autonomous navigation, the integrated strapdown inertial navigation system and refractive celestial navigation system (SINS/ RCNS) have received close attention. Aided by stellar refraction information, it can correct position and velocity errors. However, atmospheric density error is a critical element that restricts the accuracy of SINS/RCNS. To solve this problem, this article proposes a novel tightly-coupled method. In this scheme, the atmospheric density error is estimated and compensated to accommodate for the unknown model perturbation. Additionally, a tight integration model based on star pixel coordinates is derived to handle the time-varying measurement noise. The proposed method is evaluated by representative suborbital flight vehicle navigation simulations, and the results indicate that the introduction of atmospheric density error compensation can improve navigation accuracy without adding extra sensors and enhance performance.

A fast matrix generation method based on correlations is proposed for the pseudospectral method (PSM) to solve the entry trajectory optimization problem. First, the optimization problem is analyzed to obtain some assumptions of performance indicators and constraints. Then, the chain rule and correlations among the variables are used to simplify the gradient calculations, resulting in a fast generation method for the gradient vector. Meanwhile, based on the previous assumptions, a fast generation method for the Jacobi matrix is derived semi-analytically using the correlation information among the variables. Finally, the trajectory optimization problem is studied using a typical aircraft. The results are verified via comparisons with the well-known GPOPS II software. Furthermore, the superiority of the proposed method in terms of the computational efficiency is demonstrated by comparing the relevant time indexes. The performance of the proposed method in calculating the Jacobian matrix and gradient matches that of the GPOPS, combined with a relatively short solution time.

It is common in South China that rice (Oryza sativaL.) fields are seeded with a cover crop following autumn harvest. The objective was to compare the effects of different no‐tillage methods on cover crop yield, nutritive composition, and silage fermentation quality of forage wheat (Triticum aestivumL. cv. Shimai‐1) and Italian ryegrass (Lolium multiflorumL.). Cover crops were planted in winter fallow paddy fields 9 (NT9) and 5 (NT5) d prior to rice harvest and 1 d after rice harvest. Cover crops seeded prior to harvest were no‐tillage planted and cover crops seeded after rice harvest were either no‐tillage (NT1) or seeded using conventional techniques (CT1; plow followed by seeding). The cover crop biomass was determined before rice sowing in spring. Compared to NT9 and NT5, the dry matter (DM) and crude protein (CP) yields of NT1 and CT1 were slightly higher. Compared to Italian ryegrass, forage wheat had high relative feed value and DM yield. The neutral detergent fiber concentration of NT9 and NT5 was higher than NT1 and CT1 (P< .05), whereas the water‐soluble carbohydrates (WSC) concentration was lower than NT1 and CT1 (P< .05). The CP, crude fiber, and WSC concentrations of forage wheat were lower than Italian ryegrass (P< .05). Interaction between years and cover crop type were observed in silage fermentation quality (P< .05). The best sowing method for forage wheat and Italian ryegrass on winter fallow paddy fields was no‐tillage sowing after rice harvest, based upon the present study.

With the development of aerospace industry, the guidance system of an entry vehicle will be more robust, reliable and autonomous in the future. Based on fuzzy logic, the paper designs a predictor-corrector guidance law. The trajectory prediction is realized by numerical integration. The correction system is based on two fuzzy controllers, which correct the longitudinal motion and lateral motion synergistically. The error of flight range is eliminated by correcting the magnitude of bank angle. The altitude error is eliminated by correcting the attack angle. The lateral error is eliminated by regulating the reversal time of bank angle. Comparing with the traditional corrector based on Newton-Raphson iteration, the method in this paper only needs a single trajectory prediction in one correction cycle, which is favorable for on-board calculation. Moreover, the longitudinal motion and lateral motion are synergistically corrected in the predictor-corrector, which makes the method more robust and flexible.

An extension local representation and its corresponding fast approximation scheme for the computation of the gravity anomaly along glide trajectories of a hypersonic vehicle are initially proposed, involving field model reconstruction, channel model reconstruction, and onboard approximation. To meet the needs of temporary mission changes, the mathematic model for the tridimensional envelope of glide trajectories is deduced, and thus developing a universal field model by dividing the domain and assigning values to the nodes. To lighten the computational burden, a local channel model is reconstructed by the acquisition of the data of nodes for the three-level extension cells which the planned trajectory flies through. The multi-gridded scheme restrains the actual glide trajectory from flying beyond the channel while the extension approximation achieves a high-fidelity computation of the gravity anomaly. To simplify the partitioning process, a “transposed-pole” coordinate system is employed. Simulations indicate that the approximation accuracy of the extension method is over an order of magnitude higher than that of the nonextension method. The terminal positional deviations of glide trajectories due to approximation errors are beneath 1 m and 100 m on the partitioning schemes of 10km/1.2∘/1.2∘and 10km/20∘/20∘, respectively. By using the scheme of 10km/20∘/20∘, it just needs 816 memorized data and 76.781 s to achieve the computation of a glide trajectory containing 10,000 calculation points, with a 100-times enhanced trajectory accuracy. The onboard computational time for the proposed method is only 6000th of that for 1080-order spherical harmonics. The high-adaptability for temporary mission changes and the virtues of exactness, rapidity, and applicability make this method attractive for both of onboard computations and offline analysis of gravity anomaly along glide trajectories.

A novel robust adaptive gliding guidance strategy based on multi-constrained analytical optimal guidance and online identification of aerodynamic coefficients for hypersonic vehicles is proposed. The guidance models are constructed in both longitudinal and lateral directions and optimal guidance law, namely required load factor, is designed with minimum energy consumption to satisfy terminal position, altitude and flight-path angle constraints. Considering aerodynamic coefficients are the core factors in the angle-of-attack calculation, it constructs the aerodynamic models in the form of quadratic polynomial function and employs extended Kalman filter to estimate the unknown parameters. Using the optimal guidance law based on current flight states and terminal constraints and the identified outputs to calculate angle-of-attack, then the gliding guidance mission can be achieved adaptively and robustly. Finally, the simulation experiments of high performance of the common aerothermodynamics-shell vehicle (CAV-H) are carried out to validate the guidance performance.

A new trajectory generation for heat load test is proposed based on gauss pseudospectral method within limit range. Firstly, with multiple path constraints and flight task requirements taken into consideration, heat load parameters are introduced into the dynamics equations. In order to solve the problem of generating such a trajectory within limit range rapidly, the dynamics equations have been normalized by Earth related parameters. Secondly, since the gauss pseudospectral method is just employed to solve the discrete nonlinear programming problem, transformations are developed, which can relate the Lagrange multipliers of the discrete nonlinear programming problem to the costates of the continuous optimal control problem. In addtion, another approach of trajectory generation by tracking the given heat rate is also presented. Finally, simulation results with common aero vehicle (CAV-H) show that the trajectories obtained by both methods can well perform the heat load test with high stagnation heating rate and the large total aeroheating amount; meanwhile, gauss pseudospectral method is better than the compared one in the given range. Furthermore, the 3-D trajectory states and control variables, angle of attack and bank, which are generated by gauss pseudospectral method, can change smoothly.

Entry landing footprint is an important index of the flight capability of an entry vehicle. Footprint generation methods can be classified into three categories, namely, methods based on the interpolation of the drag profile, methods based on the maximum cross-range, and methods based on virtual targets. This paper proposes a procedure for improving the methods based on virtual targets method by avoiding the problem of setting virtual targets. Taking the cross-range of the vehicle as the performance index, the optimal control law is used to develop the bank angle control law. Through coordinate transformation, the optimal control problem is transformed into a univariate root-finding problem that is similar to the result of the methods based on virtual targets method. But the method in the paper is more convenient for engineering application. At last, the footprint of the EG13 mission of X-33 is generated.

A ballistic error propagation algorithm for glide trajectories of a hypersonic glide vehicle is originally proposed based on the perturbation theory. Perturbation equations that treat perturbations as external inputs and flight state deviations as state variables are established. Based on the reasonable simplification assumptions, the analytic expression of the state transition matrix is deduced and thus the ballistic error propagation model is established. A transposed coordinate frame is introduced to simplify the development of the perturbation equations and the error propagation model. By employing the gravity anomaly as the single perturbation factor, the proposed algorithm is validated and verified by numerical experiments. When compared with the traditional method, the proposed method takes only just a quarter computational costs and restrains the method errors beneath 10% of the total terminal deviations. It is an effort that initially focuses on the error propagation mechanism of the glide trajectory and the proposed model has sufficient precision for the analysis of modeling deviations, thus laying the foundation of correcting the modeling deviations and enhancing the accuracy of vehicle’s flight states.

A novel disturbance rejection control scheme is proposed to address the robust attitude control problem for the air-breathing hypersonic vehicle with actuator dynamics and disturbances based on predictive sliding mode control and nonlinear disturbance observer. To achieve attitude control subtly and precisely, the attitude control system is decomposed into two subsystems: the outer-loop subsystem and inner-loop subsystem. Different control schemes are taken to attenuate or reject model uncertainties and external disturbances, whose influences on the two subsystems are different. The predictive sliding mode control is first utilized to attenuate model uncertainties imposed on the outer-loop subsystem. Then, a novel nonlinear disturbance observer–based predictive sliding mode control is proposed to tackle the mismatched disturbances with remarkable influence on the inner-loop subsystem. Afterward, both the effectiveness and stability of the proposed nonlinear disturbance observer–based predictive sliding mode control disturbance rejection control scheme are demonstrated from the theoretical prospective. Finally, simulation results are given to present the effectiveness and robustness of the proposed disturbance rejection control scheme.

A local representation of gravity anomaly along flight trajectory ballistic missile based on the net function approximation theory and an “infundibular tunnel” generated warping a standard trajectory is proposed. Even trading exactness against computational burden, the results achieved by the proposed method have sufficient precision for trajectory calculation. Being compared with 1080-order spherical harmonics, it takes just about one-thirtieth onboard computational time and needs only about 1000 data memorized to complete the gravity anomaly computation for a 12,000 km range trajectory, with an average approximation error of about 10−2mgal and a consequent ballistic impact error beneath 8 m. The modest memory requirement and vastly decreased computational time allow this method to apply to onboard computations of gravity anomaly along any trajectory.

A novel highly constrained optimal gliding guidance algorithm, which can satisfy multiple path and terminal constraints in the presence of no-fly zones for hypersonic vehicle, is investigated in this paper. It employs line-of-sight angle to describe the relative location relationship between flight path and no-fly zones, and proposes boundaries selection algorithm for each no-fly zone, which is called avoidance strategy, with minimum energy consumption. The boundaries determined by avoidance strategy divide the flight process and guidance task into several stages. In each stage, it constructs guidance models based on quasi-equilibrium glide condition in longitudinal and lateral directions respectively, and employs optimal control to generate guidance law to satisfy terminal location, altitude, and flight path angle constraints. In addition, all the path constraints, including heating rate, dynamic pressure, and overload, are converted into the angle-of-attack constraint to ensure the guidance mission can be accomplished successfully. This algorithm is independent of standard trajectory, and all the guidance commands, including the bank angle and the angle of attack, can be calculated analytically in real time and adaptively. Finally, the simulation results of CAV-H indicate that the proposed strategy can guide the vehicle to satisfy multiple different constraints with high precision and avoid no-fly zones effectively.

A sliding mode decoupling attitude controller based on parametric commands is proposed for a generic hypersonic vehicle (GHV). This vehicle model has fast time variability and strong coupling, is highly nonlinear, and includes uncertain parameters. The design of the controller takes these features into account. First, for the purpose of decoupling, the inner loop of the controller is designed using the dynamic inversion (DI) method. Input/output linearization is achieved using full-state feedback to globally linearize the nonlinear dynamics of selected controlled outputs. Second, to improve the robustness of the attitude control system, the sliding mode control (SMC) method is used to design the outer loop of the controller. Although the DI and SMC methods result in decoupling and robustness, there exists serious inconsistency between the commands of the attitude angles and the commands of the first-order differential of the attitude angles. To solve this problem and achieve a trade-off between dynamic response speed and attitude-tracking precision, we propose a parametric method for calculating the commands of the first-order differential of the attitude angles. Finally, simulation studies are conducted for the trimmed cruise conditions of 33.5 km altitude and Mach 15, and the responses of the vehicle to the step commands of pitch angle, yaw angle, and rolling angle are examined. The simulation studies demonstrate that the proposed controller is robust with respect to the uncertain parameters and atmospheric disturbance and meets the performance requirements of the GHV with acceptable control inputs.

Three-dimensional (3D) nonlinear diving guidance strategy considering the coupling between longitudinal and lateral motions for hypersonic vehicle is investigated in this paper. It constructs the complete nonlinear coupling motion equation without any approximations based on diving relative motion relationship directly, and converts it into linear state space equation with the same relative degree by feedback linearization. With the linear equation, slide mode control with strong robustness is employed to design the guidance law, and 3D diving guidance law which can satisfy terminal impact point and falling angle constraints with high precision is obtained by substituting the previous control law into the origin nonlinear guidance system. Besides, regarding lateral overload as the standard, hybrid control strategy which can take full advantage of the excellent characters of both bank-to-turn (BTT) and skid-to-turn (STT) controls is designed to improve the guidance accuracy further. Finally, the results of CAV-H vehicle guidance test show that the algorithm can realize high accuracy guidance even if serious motion coupling exists, and has strong robustness to the path disturbances and navigation errors as well.

The fractional reaction-diffusion equations play an important role in dynamical systems. Indeed, it is time consuming to numerically solve differential fractional diffusion equations. In this paper, we present a parallel algorithm for the Riesz space fractional diffusion equation. The parallel algorithm, which is implemented with MPI parallel programming model, consists of three procedures: preprocessing, parallel solver and postprocessing. The parallel solver involves the parallel matrix vector multiplication and vector vector addition. As to the authors’ knowledge, this is the first parallel algorithm for the Riesz space fractional reaction-diffusion equation. The experimental results show that the parallel algorithm is as accurate as the serial algorithm. The parallel algorithm on single Intel Xeon X5540 CPU runs 3.3-3.4 times faster than the serial algorithm on single CPU core. The parallel efficiency of 64 processes is up to 79.39% compared with 8 processes on a distributed memory cluster system.

The fractional reaction-diffusion equations play an important role in dynamical systems. Indeed, it is time consuming to numerically solve differential fractional diffusion equations. In this paper, we present a parallel algorithm for the Riesz space fractional diffusion equation. The parallel algorithm, which is implemented with MPI parallel programming model, consists of three procedures: preprocessing, parallel solver and postprocessing. The parallel solver involves the parallel matrix vector multiplication and vector vector addition. As to the authors’ knowledge, this is the first parallel algorithm for the Riesz space fractional reaction-diffusion equation. The experimental results show that the parallel algorithm is as accurate as the serial algorithm. The parallel algorithm on single Intel Xeon X5540 CPU runs 3.3-3.4 times faster than the serial algorithm on single CPU core. The parallel efficiency of 64 processes is up to 79.39% compared with 8 processes on a distributed memory cluster system.

A hierarchy-structured predictive controller is designed and analyzed for rotation motion dynamics of a generic hypersonic vehicle (GHV). This vehicle model has fast variability, is highly nonlinear, and includes uncertain parameters. The controller contains two subsystems, the inner-fast-loop nonlinear generable predictive controller (NGPC) and the outer-slow-loop NGPC, both of which are designed by the closed-form optimal generable predictive control method. Thus, the heavy on-line computational burden in the classical predictive control method is avoided. The hierarchy structure of the control system decreases the relative degree of each subsystem and helps increase the dynamic response speed of the attitude controller. In order to improve the robustness of the control system, a feedback correction algorithm is proposed that corrects the calculation error between the predictive model and the real dynamic model. Simulation studies are conducted for the trimmed cruise conditions of an altitude of 33.5 km and Mach 15 to investigate the responses of the vehicle to the step commands of angle of attack, sideslip angle, and bank angle. The simulation studies demonstrate that the proposed controller is robust with respect to the parametric uncertainties and atmospheric disturbance, and meets the performance requirements of GHV with acceptable control inputs.

Abstract: The entry-glide guidance strategy for hypersonic vehicles that can satisfy both terminal and path constraints is investigated in this paper. We propose a quasi-equilibrium glide adaptive guidance methodology based on the quasi-equilibrium glide condition (QEGC), which innovatively utilizes the quasi-equilibrium glide phenomenon in lifting entry. With the aid of QEGC, both range and terminal velocity can be predicted analytically with high precision. The path constraints are converted into angle of attack constraints, which has been difficult to realize by using traditional predictive guidance methods. The algorithm is independent of the standard trajectory. All the guidance commands, including the bank angle and the angle of attack, are calculated analytically in real time, which endows the algorithm with sufficient adapbility. The results of a CAV-H vehicle guidance test show that the algorithm leads the vehicle along a quasi-equilibrium glide trajectory satisfying both the terminal and path constraints and has sufficient flexibility for occasional mission changes. Furthermore, the robustness of the guidance algorithm under disturbances is validated through a Monte Carlo simulation.

Abstract: An open-loop control system for hovering at any selected position on spacecraft orbit is first presented given that the satellite’s engine provides continuous finite thrust. Actually, the hovering states are unstable considering perturbations and thrust errors, so a feedback sliding mode variable structure control, which is adaptive and chattering-free, is designed. Under this feedback control scheme, the high-frequency chattering phenomenon is avoided, while the system stays highly robust at the same time. Simulation results show that the feedback control thrusts are continuous and the steady-states error can be confined to 10−4 m at the presence of uncertain perturbations. Finally, the feasibility of realizing hovering orbits is analyzed taking the “Moliya” and geosynchronous Earth orbit (GEO) satellites as examples.

Abstract: Since the inclination of frozen orbit with non-rotation of the perigee that occurs due to J 2 perturbation must be equal to the critical inclination, this regulation has restricted the application of frozen orbit a lot. In this paper, we propose two control strategies to eliminate the secular growth of the argument of the perigee for orbits that are not at the critical inclination. One control strategy is using transverse continuous low-thrust, and the other is using both the transverse and the radial continuous low-thrusts. Fuel optimization in the second control strategy is addressed to make sure that the fuel consumption is the minimum. Both strategies have no effect on other orbital parameters’ secular motion. It is proved that the strategy with transverse control could save more energy than the one with radial control. Simulations show that the second control strategy could save 54.6% and 86% of energy, respectively, compared with the two methods presented in the references.

Abstract: The Double Lunar-Swingby (DLS) periodic trajectory is a type of large-scale trajectory in Restricted Three-Body Problem framework. First, the principium of the DLS periodic trajectory is studied, and a preliminary design of the DLS trajectory is developed by the Patched Conic method. Second, the solution space of the DLS periodic trajectory is discussed in detail and in combination with numerical simulation, a distribution about orbital parameter relationship in the solution space is given. Finally, the variations of the orbital elements with different rotation angular velocities of geocentric apsidal line are found, and two typical orbits are given according to three reference frames. It is shown that Patched Conic method is feasible for the DLS periodic trajectory solution space analysis, and the conclusions will be valuable to the deep-space exploration orbit design in future.

Rice caryopses are enclosed by outer glumes. The size and dimension of the outer glume are the main determinants of caryopsis size. However, it is unclear whether caryopsis development is completely dependent on the size of the glume, or whether it can grow and expand autonomously despite the constraint of glume enclosure. We report the identification of a mutant line that produces normal-sized glumes with smaller mature caryopses that do not fill the entire glume cavity. The caryopsis phenotype in the pex1 mutant is caused by a reduction in cell size. OsPEX1, a leucine-rich repeat extensin gene, was highly expressed in the developing caryopsis. Overexpression of OsPEX1driven by a constitutive promoter recapitulated the mutant phenotype, showing that the small-caryopsis phenotype is caused by overexpression of the OsPEX1gene. Free amino acids, including several essential amino acids, and crude protein were increased in pex1relative to the wild type, endowing pex1with improved nutritional quality. Our results suggest that caryopsis development can be genetically uncoupled from maternally controlled glume development and that OsPEX1might be a new resource for improving nutritional quality of rice cultivars.

To track a non-cooperative hypersonic glide vehicle (HGV) without any precise information, an approach to the state estimation is presented based on a robust UKF-based filter (RUKFBF) in this paper. The HGV has an uncertain reentry motion because of unknown maneuvers which is a primary factor leading to degradation of tracking accuracy. Aiming at enhancing accuracy, the strong tracking algorithm (STA) is introduced to addressing the model error caused by a bank-reversal maneuver of HGV. Furthermore, the Huber technique is employed to deal with possible measurement model errors. In the RUKFBF, mutual interferences are suppressed between the STA and the Huber technique via two strategies. The one is that the calculation of the fading factor in the STA adopts an unmodified measurement noise covariance, and the other one is that two judgment criteria are proposed to limit large fading factors in the presence of measurement model errors. To simulate real tracking scenarios, the RUKFBF is tested through tracking a HGV trajectory considering a practical guidance strategy. Simulation results demonstrate the effectiveness of the RUKFBF in the presence of model errors and the observability of the estimated state.

•The motion and aerodynamic models of hypersonic morphing vehicle is established under the influence of morphing.•The IGCM(integrated of guidance, control and morphing) method in gliding phase is developed.•The IGCM method played a role of morphing characteristic in improving the flight performance.•This paper provided a deeper insight for the flight control system of hypersonic morphing vehicle.