Missile Control Research Articles

Integrated cooperative guidance and control of strapdown missiles

Integrated cooperative guidance and control of strapdown missiles

Fixed-Time Anti-Saturation Tracking Control for Agile Missiles with Multiple Actuators

This paper investigates the fixed-time tracking control problem for agile missiles with multiple heterogeneous actuators in the presence of saturation constraints and external disturbances. To reduce the turning radius and promote maneuvering envelope, a novel combination scheme for blended actuators is introduced in this paper, consisting of a flexible mechanism control system (FCS), reaction-jet control system (RCS), and aerodynamic control. Based on the proposed nonsingular terminal sliding mode surface, a fixed-time anti-saturation controller with an auxiliary system is presented first to ensure global fixed-time stability and to compensate for the adverse effects of input saturation. Subsequently, a fixed-time disturbance observer is constructed to estimate uncertainties and lumped disturbances, and to address the chattering problem. To assign the total virtual control command to different actuators, a control allocation based on dynamic programming considering actuator dynamics is established. Finally, detailed numerical simulations and comparisons are provided to verify the effectiveness and superiority of the proposed control scheme.

Flutter Optimization of Carbon/Epoxy Plates Based on a Fast Tree Algorithm

This study focuses on optimizing carbon/epoxy laminate configurations to maximize the flutter speed of composite structures using a Fast Tree Regression algorithm. Initially, a seed dataset was created, using finite element method (FEM) modal analysis for common stack-ups used in composite fins and UAV components. The FEM analysis, based on the Lanczos algorithm for extracting modal frequencies in bending and torsion, was verified through experimental modal analysis using an AS-4/3501-6 composite system. Custom software was developed to interface with the FEA modal software, enabling the generation and augmentation of laminate dataset scenarios. The seed dataset was expanded until the coefficient of determination (R2) reached at least 0.95. Various regression algorithms, including Fast Forest Regression, Fast Tree Regression, Sdca Regression, and Lbfgs Poisson Regression, were evaluated. The Fast Tree Regression algorithm was selected for further analysis due to its superior performance. This algorithm was applied to a design space of nearly 2000 potential laminate candidates, focusing on symmetric lay-ups to avoid undesirable coupling between bending and torsion in UAV and missile control surfaces. The final optimized lay-ups, exhibit the highest Delta function values (the squared difference of modal frequencies in torsion and bending), indicating the expected highest flutter speeds. The results demonstrate the efficacy of tailored composite materials in achieving specific aerodynamic performance goals.

Solving Advanced Missile Robotic Control Problem Via Integral Rohit transform

The problem of robotic control of an advanced missile requires designing control systems for remote-controlled missiles with sufficient abilities. These control systems need to handle navigation, guidance, propulsion, and potentially other tasks like target acquisition and avoidance of obstacles. The various aspects of missile dynamics are described by complex and non-linear differential equations. Due to this, it becomes difficult to obtain their analytical solutions. During system design and analysis, to solve these complex and non-linear differential equations, numerical techniques like Euler’s technique, the Runge-Kutta technique, or more advanced mathematical techniques are generally used. The advanced missile robotic control problem is one of the problems represented by second-order linear differential equations. In this paper, the integral Rohit transform (RT) has been applied to solve an advanced missile robotic control problem. This transformation has never been applied in working out the advanced missile robotic control problem. This paper applies a new technique for solving the second-order linear differential equation representing the advanced missile robotic control problem to obtain its required turn angle so that it will be able to catch and destroy the attacker. The necessary graphs are plotted to illustrate the numerical solution of the robotic control of an advanced missile. It reveals that the integral Rohit transform (RT) technique is an effective technique to solve the advanced missile robotic control problem.

Design and comparison of particle swarm optimization tuned Kalman filter based linear quadratic Gaussian controller and linear quadratic regulator for surface to air missile guidance system

AbstractThe study of missile guidance systems is a well‐known nonlinear control engineering area of research. To enhance the control performance of a missle guidance system, several technologies have been proposed in existing works. To resolve the weighting matrix selection issue of a linear quadratic Gaussian (LQG) controller for the surface‐to‐air missile guidance control system, this study utilizes the particle swarm optimization (PSO) technique. Selecting the best state (Q) and input (R) weighting matrices is a significant difficulty in the design of the LQG controller for real‐time applications since it affects the controller's performance and optimality. The weighting matrices are often chosen by a trial‐and‐error method that not only complicates the design but also does not yield optimal outcomes. Therefore, in this paper, a PSO method is developed and used in the design of the linear quadratic regulator (LQR) and LQG controllers for the surface‐to‐air missile control system to choose the elements of the Q and R matrices in the best possible way. Finally, a comparative analysis between the designed controllers was presented. The results shows that a good performance was achieved by using the proposed PSO‐tuned design process. The LQG and LQR are designed by manually adjusting the weighting matrices and utilizing an intelligent procedure, PSO algorithm which achieved optimal results. Further results indicate that the designed controllers, the PSO tuned LQR and LQG achieved a better performance over the manually adjusted LQR and LQG controllers.

Aerodynamic Modeling of a Missile Combining Transfer Learning and Dendritic Net

During the initial stages of missile design, finding an efficient method for analyzing aerodynamic characteristics is crucial. This paper proposes a novel aerodynamic modeling method based on a limited computational fluid dynamics (CFD) dataset, combining transfer learning (TL) with Dendritic Net (DD). Initially, we employ CFD-calculated aerodynamic data to establish a pretrained model using DD. Subsequently, the model is adapted to the target domain by TL, predicting aerodynamic parameters under specific conditions. The overall aerodynamic parameters are utilized to generate a relational spectrum through DD’s white-box features, from which primary features are extracted to establish an aerodynamic polynomial model. Finally, the model’s practicality is validated by ballistic flight simulations. The innovation lies in leveraging DD to generate a relational spectrum of aerodynamic parameters, leading to a high-precision polynomial model. Research shows DD outperforms traditional cell-based networks in predicting aerodynamic parameters, and TL reduces the CFD computation workload in the target domain by 3/4 while maintaining prediction accuracy. The polynomial model exhibits superior accuracy compared to the empirical fitting formulas. The method reduces the computational workload for aerodynamic data collection, and through system identification, a high-precision polynomial model is obtained, which provides a reliable basis for missile controller design.

High-Altitude Terminal Control of Anti-Air Missiles With a Terminal Booster and Front Lateral Impulse Thrusters

High-Altitude Terminal Control of Anti-Air Missiles With a Terminal Booster and Front Lateral Impulse Thrusters

Command filtered integrated estimation guidance and control for strapdown missiles with circular field of view

In this paper, an integrated estimation guidance and control (IEGC) system is designed based on the command filtered backstepping approach for circular field-of-view (FOV) strapdown missiles. The three-dimensional integrated estimation guidance and control nonlinear model with limited actuator deflection angle is established considering the seeker's FOV constraint. The boundary time-varying integral barrier Lyapunov function (IBLF) is employed in backstepping design to constrain the body line-of-sight (BLOS) in IEGC system to fit a circular FOV. Then, the nonlinear adaptive controller is designed to estimate the changing aerodynamic parameters. The generalized extended state observer (GESO) is designed to estimate the acceleration of the maneuvering targets and the unmatched time-varying disturbances for improving tracking accuracy. Furthermore, the command filters are used to solve the "differential expansion" problem during the backstepping design. The Lyapunov theory is used to prove the stability of the overall closed-loop IEGC system. Finally, the simulation results validate the integrated system's effectiveness, achieving high accuracy strikes against maneuvering targets.

Koopman Operator-Based Integrated Guidance and Control for Strap-Down High-Speed Missiles

Koopman Operator-Based Integrated Guidance and Control for Strap-Down High-Speed Missiles

Distributed observer‐based fixed‐time cooperative guidance law against maneuvering target

SummaryThis paper presents a fixed‐time cooperative guidance law for leader‐following missiles, comprising one leader missile with the target seeker and several seeker‐less follower missiles. The aim is to achieve a simultaneous attack on a maneuvering target at desired impact angles. First, a guidance law with impact angle control for the leader missile against a maneuvering target is proposed based on nonsingular fast terminal sliding mode (NFTSM) control algorithm. Then, the design of cooperative guidance law for the follower missiles is composed of two parts: along the follower‐to‐leader line of sight (LOS) direction, the guidance command derived from bi‐homogeneous property is designed to ensure that the follower‐leader ranges keep proportional consensus with the range‐to‐go of the leader missile, thus avoiding the estimation of time‐to‐go (); in the normal follower‐to‐leader LOS direction, considering the relative impact angle constraints which is determined by the leader LOS angle, the guidance command is proposed based on predefined‐time sliding mode control method. What's more, a distributed fixed‐time observer is designed for the follower missiles to compensate for unobtainable leader missile information. The fixed‐time stability of the proposed methods is demonstrated using the Lyapunov theory and bi‐homogeneous property. Finally, simulation results confirm the effectiveness and superiority of the proposed fixed‐time cooperative guidance law with leader‐following strategy.

Integrated Controller for Divert Thruster Flight Propulsion Control Systems

Future generation missile calls for development of fast response propulsion based control systems to achieve hit-to-kill miss distance against highly manoeuvrable targets covering high-endo to exo-atmosphere regions. Control systems based on solid propulsion are developed connecting multiple pintle nozzles and control thrust vector is generated with distribution hot gasses in pitch/yaw directions. Differential distribution of hot gasses among multiple nozzles is complex due to time varying coupled non-linear chamber pressure dynamics with propellant combustion and nozzles’ flow phenomena and methods based on linear control may not ensure stability in wide operating conditions. There is need to develop "Unified Controller" based on non-linear formulation to ensure control stability in wide operating conditions of various mission applications, with advanced features for new generation missiles to counter various futuristic targets, and achieve hit-to-kill capabilities following integrated approach in order to improve the total system performance. Non-linear algorithms proposed in the recent literature do not exploit synergism between plant and actuation systems dynamics. Present paper presents novel non-linear feedback linearization technique, Dynamic Inversion, a relatively straightforward approach in Integrated Control Framework (ICF) implementing inherent time scale separation between solid motor plant and hot gas flow control valve actuation system. To ensure stability in various operating conditions and assure robust performance in the presence of parameter inaccuracies, controller is augmented with model-following neuro-adaptive design. Prototype systems: Thrust Controlled Motor (TCM) and Divert Thruster Flight Propulsion Control Systems (DTFPCS) are developed to demostrate/validate "Unified Controller" for missile control system. Closed loop control of chamber pressure is demonstrated with single pintle nozzle system and control thrust vector generation with multiple nozzle systems. Model update takes place adaptively online and unlike a typical indirect adaptive control approach, there is no need to update the individual parameters explicitly. Instead the inaccuracy in the system output dynamics is captured directly and then used in modifying the control. Based on present work, missilecontrol systems for various applications can be developed with limited controller changes and thereby minimizing number of developmental tests and cost.

Flow Field Simulation Tool of Solid Propulsion Control Systems for Missile Applications

In order to achieve hit-to-kill miss distances against manoeuvrable ballistic missile targets, future generation missiles calls for fast response non-conventional propulsion control systems during terminal homing period in high-endo to exo-atmosphere regions augmenting aero control. Based on advances in thrust modulation controlling throat area in solid propulsion pintle motor, control systems are developed for missile Divert and Attitude Control Systems (DACS) applications using multiple nozzles in pitch/yaw directions connected to common gas generator. Control thrust vector for lateral and attitude corrections is generated with proportional distribution of total thrust in pitch/yaw directions through real time thrust modulation of pintle nozzles
 Towards development of propulsion control systems based on solid propulsion, prototype systems: Thrust Controlled Motor (TCM) and Divert Thruster Flight Propulsion Control System (DTFPCS) are developed to demonstrate thrust modulation/ control thrust vector generation in solid propulsion and finalize unified controller for various missile control applications. Design & development process of prototype systems calls for flow field simulation tool for parametric design analysis/optimization and generate performance maps/control parameters based on detailed flow distributions. Present paper presents flow field simulation tools with Steady Flow Field (SFF) model and Dynamic Flow Field (DFF) model integrating dynamics of pintle movement with steady flow solver. Parametric analysis of geometrical profiles of pintle/throat regions and effect of pintle speed on system response are presented for system design optimization. Performance maps and controller maps of prototype systems are generated based on flow field distributions for nozzle thrust modulation. Simulated results are compared with open loop hot tests and unified controller parameters are updated for control thrust vector generation. Finally flow field distributions of DTFPCS operating modes: neutral-thrust and lateral-thrust are presented demonstrating the utility of simulation tool in design analysis and system development. Present simulation tool is critical in system design optimization and unified controller development for various flight control applications with minimum number of developmental tests. Further work of integrating propellant grain geometry variation during motor hot tests, with flow field model is in progress to predict control system performance for various missile control applications.

Three-dimensional low-order fixed-time integrated guidance and control for STT missile with strap-down seeker

Strap-down seeker is rigidly fixed onto the missile body, which results in detection information being coupled to the missile’s attitude and having a narrow field-of-view (FOV). During the terminal guidance flight, attitude adjustment of the missile may lose the target’s lock and reduce interception accuracy. Therefore, this paper investigates three-dimensional integrated guidance and control (IGC) under the constraints of the FOV and roll angle for skid-to-turn (STT) missile with strap-down seeker. A new low-order IGC model is constructed by establishing a second-order model of body line-of-sight (BLOS) angle based on strap-down decoupling theory and combining it with the second-order roll angle equation. Furthermore, a low-order fixed-time IGC scheme is developed using the integral barrier Lyapunov function (iBLF) to limit BLOS and roll angles. Fixed-time filter, which avoids the “complexity explosion” caused by conventional back-stepping technique, is utilized for obtaining virtual control command and its derivative. A fixed-time disturbance observer is introduced to compensate for the lumped disturbance. According to Lyapunov stability theory, it is proven that the proposed IGC scheme can make the closed-loop system converge within a fixed time. Finally, the effectiveness and robustness of the IGC scheme are verified by various numerical simulations.

METHOD OF DATA IDENTIFICATION IN THE SYSTEM OF INFORMATION SUPPORT OF ANTI-AIRCRAFT MISSILE UNITS BASED ON THE INTERPOLATION METHOD

The issue of making timely decisions in the control system of anti-aircraft missile units in order to ensure the rapid detection of air targets and their timely firing at long distances requires constant attention from military specialists of the leading countries of the world. The article presents the results of developing a methodology for identifying data in the information support system of anti-aircraft missile units based on the interpolation method. The object of research is the process of data identification in the information support system of anti-aircraft missile units. The subject of research is data interpolation methods. The purpose of the research is to develop a methodology for identifying data in the information support system of anti-aircraft missile units based on the interpolation method. Conclusions. An algorithm has been developed that implements a methodology for identifying the targeting data of the air defense missile control center, obtained from data from radio engineering troops, with the data of the unit's own or attached reconnaissance and targeting station and allows to increase the accuracy of combat information. To determine that the marks from the target received from the reconnaissance and targeting station and from the control center of the air defense missile unit are marks of the same target, an interpolation procedure is performed, provided that the data received from both sources is secondary information of the target observation vector. The interpolation procedure itself involves the formation of a spatial identification strobe and a comparison of the target trajectory obtained from the trace data of the own (supporting) reconnaissance and targeting station and the interpolated data of the target's movement relative to the latest external targeting data in the opposite direction. This algorithm can be used to implement the relevant tasks in the complex of automation tools for the control center of military units of air defense missile forces, automated workstations of commanders of air defense missile forces, which will reduce the time for searching and detecting air targets by the missile guidance station of the air defense missile system and directly increase the firepower of these units.

RESEARCH OF AIMING SYSTEMS FOR MILITARY OBJECTS

The formation of electronic warfare is mutually conditioned by the dynamics of the struggle of means of attack and defense. Electronic combat, which is a form of operational and combat support, has become a new element of the content of operations and combat operations. One of the main directions of development of means, complexes and methods of electronic warfare is the improvement of the element base and technical solutions in the construction of electronic warfare equipment. Another direction is associated with a change in conceptual provisions associated with the creation and implementation of new technologies. For the successful solution of the problem, a brief overview of the currently existing and operating self-directed systems is given, their structure (transmitters) is considered, and the algorithm of the missile's approach to the target is considered. The structure of existing missiles and the requirements for its parts were considered. In comparison, missiles produced by different countries were analyzed. Various dispositions of electromagnetic waves are used in systems for missile control. Based on the ranges used, there are Radio-Technical, infrared, optical (laser) control systems. Also, the methods of aiming were considered: active, semiactive, passiv. Keywords: Self-directed head, aiming methods, launch of the rocket to the visible and invisible targets.

Robust missile autopilot design based on dynamic surface control

Since the dynamical system and control system of the missile are typically nonlinear, an effective acceleration tracking autopilot is designed using the dynamic surface control (DSC) technique in order to make the missile control system more robust despite the uncertainty of the dynamical parameters and the presence of disturbances. Firstly, the nonlinear mathematical model of the tail-controlled missile is decomposed into slow acceleration dynamics and fast pitch rate dynamics based on the naturally existing time scale separation. Secondly, the controller based on DSC is designed after obtaining the linear dynamics characteristics of the slow and fast subsystems. An extended state observer is used to detect the uncertainty of the system state variables and aerodynamic parameters to achieve the compensation of the control law. The closed-loop stability of the controller is derived and rigorously analyzed. Finally, the effectiveness and robustness of the design is verified by Monte Carlo simulation considering different initial conditions and parameter uptake. Simulation results illustrate that the missile autopilot based DSC controller achieves better performance and robustness than the other two well-known autopilots. The method proposed in this paper is applied to the design of a missile autopilot, and the results show that the acceleration tracking autopilot based on the DSC controller can ensure accurate tracking of the required commands and has better performance.

Design of Missile Guidance Law Using Takagi-Sugeno-Kang (TSK) Elliptic Type-2 Fuzzy Brain Imitated Neural Networks

The exploiting of missile guidance law is one of the most important issue of defense systems. However, it is a complex nonlinear guidance control problem. In recent years, several intelligent algorithms have been employed for the missile guidance law design. This paper aims to provide a more effective intelligent neural network, and then apply it to missile guidance control. An elliptic type-2 function (ET2F) combined with a Takagi-Sugeno-Kang (TSK) fuzzy system (FS) based on a wavelet function and a brain imitated neural network (BINN) is proposed to produce a new Takagi-Sugeno-Kang elliptic type-2 fuzzy brain imitated neural network (TSKET2FBINN). The proposed TSKET2FBINN is then incorporated into the missile guidance law. The proposed missile guidance control system includes the TSKET2FBINN controller and a robust compensation controller. A Lyapunov function is used to generate parameter adjustment adaptive laws so as to guarantee system stability with fast tracking performance of missile guidance control system. By presenting three missile control scenarios, the effectiveness of the proposed method is then demonstrated. The miss-distance (MD) of the proposed method is calculated and compared to other recent guidance methods to demonstrate its superior performance.

Numerical Investigation on Transient Effect of Jet Interference Characteristics of Lateral-Jet-Controlled Spinning Missile

At present, there is no publicly published research on the unsteady interference effect in the start-up process of the lateral jet control of the spinning missile. The variation of aerodynamic characteristics during the jet start-up process of the spinning missile is still unclear. Therefore, the unsteady numerical method based on the three-dimensional unsteady compressible Navier–Stokes equations and the sliding mesh method is used to study the unsteady jet interference characteristics of the spinning missile during the starting process of the lateral jet. Based on the verification of the numerical simulation method in this paper, the jet interference flow field under the conditions of non-rotation and rotation is simulated, and the variation of the aerodynamic characteristics of the missile under the two conditions is given. The influence of rotation on the unsteady aerodynamic characteristics of the lateral-jet-controlled spinning missile is analyzed. The flow mechanism resulting in the change of the jet control characteristics and the lateral aerodynamic characteristics of the missile is analyzed through the interference flow field structure at different moments after the jet starts. The results indicate that in the start-up process of pulse jet control, the jet interference characteristics on the fins have a delay effect compared with the projectile body. The duration of the unsteady effect caused by the high-pressure region upstream of the nozzle is shorter than that caused by the low-pressure region downstream of the nozzle. The flow separation and reattachment near the nozzle have strong unsteady characteristics. The jet wake has the most obvious interference effect on Fin1. The pressure on the side of the rotation direction of Fin1 increases, while the opposite side is in contrast.

Coning motion stability and decoupling methods analysis of spinning missiles with angle‐of‐attack feedback autopilot

AbstractThe angle‐of‐attack (AOA) three‐loop feedback autopilot is an improved three‐loop autopilot that has been widely employed in missile control systems. For spinning missiles, however, unstable coning motion can be induced by the cross‐couple effect. For spinning missiles with an AOA feedback autopilot, this paper analyzes the coning motion stability with the consideration of the augmentation loop and the position of the accelerometer and compares the performance of three decoupling methods. First, a novel double‐channel actuator AOA three‐loop autopilot is established, and the sufficient and necessary condition of coning motion stability is proposed analytically on account of the complex system equations. The stability condition shows that the stable region of the design parameters for the autopilot shrinks as a result of the spinning condition. Moreover, methods associated with actuator dynamics, control coupling, static stability, and the decoupling method of setting the lead angle to the control system are presented to improve the stability of spinning missiles. Numerical simulations are implemented to demonstrate the accuracy of the proposed methods, whose results illustrate that the stability conditions can guide AOA autopilot design for the flight stabilization of spinning missiles.

Attention-CNN 을 이용한 유도탄 비행데이터의 이상성 검출 기법 연구

This study proposes a new deep learning-based anomaly detection algorithm in a supervised framework for the Monte-Carlo (MC) simulation data of a missile control system. First, in a similar fashion to the famous BERT(Bidirectional Encoder Representations from Transformers) algorithm in NLP(Natural Language Programming), a pre-trained transformer-based encoder is utilized to provide an alternative representation of time-series data, replacing conventional data-preprocessing. For a more direct perception of differences in normal and abnormal data, a multi-head attention score is also considered as an input of a two-dimensional convolutional neural network classifier along with the output of transformer encoder. The training of the proposed framework is comprised of two steps: unsupervised pre-training of the transformer encoder with all generated MC simulation data and supervised training of the classifier with labelled data. To generate the MC simulation data, the high-fidelity missile 6DOF simulation program is developed with random variables that represent the uncertainties of realistic scenarios. The resulting anomaly detection performance from the generated MC simulation dataset indicates that the proposed framework provides significantly better detection performance than other supervised machine/deep learning-based algorithms. Furthermore, using a multi-head attention score from the transformer encoder as an input of the classifier not only improves the detection performance but also contributes to reducing the necessity of labelled train data. Hence, the proposed method has the potential to greatly reduce the human effort in detecting anomalies in MC simulation data.