Multiple Launch Rocket System Research Articles

Modelling the suitability of multiple launch rocket system in the war in Ukraine

Since the war started, both Russian and Ukraine forces have been using Multiple Launch Rocket System (MLRS). Theoretically, the heated particulate matter residuals from MLRS could be captured by satellite imageries, but this premise has never been tested. In this study, the Fire Information for Resource Management System (FIRMS) data were analyzed to identify anthropogenic thermal anomalies resulting from the war in Ukraine. The research team examined the frequency of Feb–June FIRMS in both long-term (2001–2021) and short-term trends (2022), as well as the recency of last FIRMS date. In addition, other crucial factors like site control and the proximity of nearby Russian troops are also considered in developing this suitability model. Human analysts with military knowledge, understanding of standard operating procedure and the strategic importance of a developing battlefield were deployed to identify potential tactical firing locations. The proposed model was developed on Google Earth Engine for ease of distribution and deployment. Four case studies are demonstrated to illustrate the implemented model, interpreted in the context of ongoing conflicts and verified by geospatial intelligence crowdsourced and/or reported by the public and social media. This study provides counter-MLRS geospatial intelligence from crowdsourced data and publicly available satellite imagery.

A new method for evaluating the firing precision of multiple launch rocket system based on Bayesian theory

How to effectively evaluate the firing precision of weapon equipment at low cost is one of the core contents of improving the test level of weapon system. A new method to evaluate the firing precision of the MLRS considering the credibility of simulation system based on Bayesian theory is proposed in this paper. First of all, a comprehensive index system for the credibility of the simulation system of the firing precision of the MLRS is constructed combined with the group analytic hierarchy process. A modified method for determining the comprehensive weight of the index is established to improve the rationality of the index weight coefficients. The Bayesian posterior estimation formula of firing precision considering prior information is derived in the form of mixed prior distribution, and the rationality of prior information used in estimation model is discussed quantitatively. With the simulation tests, the different evaluation methods are compared to validate the effectiveness of the proposed method. Finally, the experimental results show that the effectiveness of estimation method for firing precision is improved by more than 25%.

Аналіз робіт з модернізації ЗСЗВ 9К51 «Град» для визначення технічних характеристик перспективного некерованого РС калібру 122 мм

The article dwells on the multiple launch rocket systems with high firepower, firing rate and manoeuvrability, which continue to be one of the basic means of destruction of the land forces in the conditions of the modern armed conflicts. Authors observed the importance of reconstruction and upgrading of multiple launch rocket systems of Grad 9К51, Hurricane 9К57 and Tornado 9К58 types and missiles they use by the enterprises of the domestic military-industrial complex. The article dwells on the main areas of upgrading of the multiple launch rocket system Grad 9K51 performed by NPO Splav and co-operating enterprises in 1997‒1998 for a foreign customer. The key factors that allowed improving the performance of the Grad system in the upgrading process are identified in this article. The main characteristics of the unguided missiles 9M217, 9M218, 9M521, 9M522, designed for the foreign customer, had been investigated. The performance characteristics of the Tornado-G multiple launch rocket system which went into service with the Ministry of Defense of the Russian Federation in 2014, as well as the family of the upgraded unguided missiles 9M538, 9M539, 9M641, are analyzed. The article identifies the main areas of work for further improvement of the performance characteristics of the 122-mm unguided missile, developed by Yuzhnoe Design Office for the multiple launch rocket system 9K51 Grad. This article can be useful for the specialists in development of new and upgrading outdated systems of rocket weapons. Key words: multiple launch rocket system (MLRS), missile, 9K51 Grad, 9M217, 9M218, 9M521, 9M522, Tornado-G, 9M538, 9M539, 9M541.

Dynamic Simulation of Multiple Launch Rocket System Marching Fire Based on the Fuzzy Adaptive Sliding Mode Control

This paper presents a servo control method for the multiple launch rocket system (MLRS) launcher during marching fire operations. The MLRS, being a complex nonlinear system, presents challenges in designing its servo controller. To address this, we introduce the fuzzy adaptive sliding mode control (FASMC) approach. The permanent magnet synchronous motor (PMSM) and controller of the MLRS were simulated in the MATLAB/Simulink environment. The dynamic model of the MLRS during marching fire was established using multi-body system theory, vehicle mechanics, and launch dynamics. The dynamic model was then integrated with the FASMC-based controller using the Adams/View module. Numerical calculations were performed to demonstrate the control performance and the effectiveness and applicability of the proposed approach were validated through a comparison experiment between FASMC and other common control methods.

A simplified dynamic model and control for a multiple launch rocket system

Multiple launch rocket system, a type of launching platform used to launch kinetic load to hit the target, is an extremely complicated mechanical system with strong vibration because of the jet force. In this study, a nonlinear dynamic model and vibration control of a multiple launch rocket system are presented to reduce vibration and improve position accuracy. A simplified dynamic model of the multiple launch rocket system is derived using the Newton–Euler method, which facilitates the controller design considering the strong complexity of the multiple launch rocket system. On this basis, the feedback linearization technique is introduced to design a nonlinear controller based on the deduced dynamic model. The simulated and experimental results show that the simplified dynamic model–based control effectively can reduce vibration level of the launching system and make the azimuth and elevation angles reach the desired values with smaller error despite of each rocket’s jet force.

On modeling and dynamics of a multiple launch rocket system

Dynamics analysis is currently a key technique to fully understand the dynamic characteristics of sophisticated mechanical systems because it is a prerequisite for dynamic design and control studies. In this study, a dynamics analysis problem for a multiple launch rocket system (MLRS) is developed. We particularly focus on the deductions of equations governing the motion of the MLRS without rockets by using a transfer matrix method for multibody systems and the motion of rockets via the Newton–Euler method. By combining the two equations, the differential equations of the MLRS are obtained. The complete process of the rockets’ ignition, movement in the barrels, airborne flight, and landing is numerically simulated via the Monte Carlo stochastic method. An experiment is implemented to validate the proposed model and the corresponding numerical results.

A novel launch dynamics measurement system for multiple launch rocket system and comparative analysis with numerical simulations

In this paper, a novel launch dynamics measurement system based on the photoelectric sensor pair is built. The actual muzzle time (i.e. a time duration that originates from the initial movement to the rocket’s departure from the muzzle) and the muzzle velocity are measured. Compared with the classical methods, the actual muzzle time is obtained by eliminating the ignition delay. The comparative analysis method is proposed with numerical simulations established by the transfer matrix method for multibody systems. The experiment results indicate that the proposed measurement system can effectively measure the actual muzzle time and reduce the error of classical methods, which match well with the simulation results showing the launch dynamics model is reliable and helpful for further analysis and design of the MLRS.

A Novel Vibration Control System Applying Annularly Arranged Thrusters for Multiple Launch Rocket System in Launching Process

Multiple Launch Rocket System (MLRS) has been widely used in recent years; vibration control in launching process is an effective way to improve its dispersion characteristics. In this paper, a novel vibration control system applying Annularly Arranged Thrusters (AAT) for MLRS in launching process is introduced and the prototype of the proposed system is built. The dynamic model of the MLRS with the AAT is established based on the Transfer Matrix Method for Multibody Systems (MSTMM). The LQR-PID control law and the management for the AAT are presented. The simulation and experiment of the proposed system are carried out and analyzed. The results show that the vibration of MLRS is effectively attenuated by the proposed control system. The study in this paper provides a new idea to improve the dispersion characteristic by reducing the vibration of MLRS in launching process.

Creep prediction of GFRP directors in a multiple launch rocket system under long-term stacking storage

During long-term stacking storage, creep deformation of polymeric composite directors used in multiple launch rocket systems can appear, which affects rocket launch. In this work, E-glass/epoxy 6509 composite laminates were prepared and 60/60 min creep/creep-recovery tests were carried out in the transverse and shear directions at different stress levels. Parameters of the Schapery’s nonlinear viscoelastic equation were obtained based on the test data. Then, a three-dimensional nonlinear viscoelastic constitutive model based on Schapery’s equation was implemented in the standard finite element code UMAT and a finite element model was developed to predict the creep deformation of the composite directors after 15 years of stacking storage. The effect of creep deformation on rocket launching was also studied. The results show that the residual deformation of the directors is a saddle-shaped distribution in three-dimensional space, the maximum residual deformation is 0.24 mm, and the minimum residual deformation is 0.22 mm. The creep deformation of the director causes a significant increase in the contact-collision force during launching, resulting in a decrease in the rocket run-off track velocity.

Exhausted jet caused the deformation of front metal seal covers in a multiple launch rocket system

During the launch tests of a Multiple Launch Rocket System (MLRS), the front metal seal covers on unlaunched tubes had plastic deformation and felled to the ground. More seriously, the rocket exhausted jet directly caused damage to some of the unlaunched rockets projectiles. As the rocket exhausted jet impinged on the cover, high temperature and high pressure jet caused plastic deformation of the covers. So the temperature and pressure of exhausted jet acting on the surface of the cover were measured. Then pressure data were used to estimate the strain of front cover on adjacent launch tube caused only by pressure. And temperature data were used for thermal stress analysis of the cover. Furthermore, the triaxial strain curves of the cover were obtained during a flight test in which a 252-mm diameter rocket projectile was launched from the MLRS. The results demonstrated that plastic deformation of the covers is mainly due to the thermal deformation caused by the high temperature, which provided guidance for optimal design of front seal covers. No plastic deformation was found in the modified covers during subsequent launch tests of the MLRS.

Neural-network-predictor-based control for an uncertain multiple launch rocket system with actuator delay

Development of multiple launch rocket system (MLRS) has been restricted for several decades due to the poor dispersion characteristics of rockets, which is caused by the orientation of the MLRS departing from that intended. Hence, it is vital to maintain the angles of MLRS at a desired value via a proper control strategy. In this paper, a new neural network predictive control is developed for orienting control of the MLRS with actuator delay. First, the dynamic model of motor-mechanism coupling system is established using Lagrange method and field-oriented control theory. Then, for cancelling the effects of nonlinearities and uncertainties, the concept of feedback linearization and a dynamic recurrent neural network are introduced. In addition, a modified Smith predictor is employed to maintain the desirable orienting performance in the occurrence of actuator delay. For the stability analysis, Lyapunov’s method is utilized to ensure uniform ultimate boundedness of the closed-loop system. The simulated and experimental results demonstrate the effectiveness of the proposed controller.

Efficient Method of Firing Angle Calculation for Multiple Launch Rocket System Based on Polynomial Response Surface and Kriging Metamodels

Aiming at solving the problem of firing angle calculation for the multiple launch rocket system (MLRS) under both standard and actual atmospheric conditions, an efficient method based on large sample data and metamodel is proposed. The polynomial response surface, Kriging, and the ensemble of metamodels are used to establish the functional relations between the firing angle, the maximum range angle, the maximum range, and various influencing factors under standard atmospheric conditions, and related processes are described in detail. On this basis, the initial values for the first two iterations are determined with the meteorological data being made full use of in the six degrees of freedom trajectory simulation, and then the firing angle corresponding to a specific range is automatically and iteratively calculated. The efficient method of firing angle calculation for the typical MLRS has been extensively tested with three cases. The results show that the high-order polynomial response surface, the Kriging predictors with Cubic, Gauss, and Spline correlation functions, and the ensemble of above four individual metamodels have better performances for predicting the firing angle under standard atmospheric conditions compared with those of other metamodels under identical conditions, and execution times of the above four individual metamodels with a training sample size of 9000 are all less than 0.9ms, which verifies the effectiveness and feasibility of the proposed method for calculating the firing angle under standard atmospheric conditions. Moreover, the number of iterations is effectively reduced by using the proposed iterative search approach under actual atmospheric conditions. This research can provide guidance for designing the fire control and command control system of the MLRS.

A Study on the Reliability Growth of Multiple Launch Rocket System Using Accelerated Life Testing

A Study on the Reliability Growth of Multiple Launch Rocket System Using Accelerated Life Testing

Study on test dynamics method of non-full loading firing for multiple launch rocket system

Abstract This paper studies the test dynamics method of non-full loading firing for multiple launch rocket system (MLRS), and provides a new method for dynamics analysis of the MLRS coupled with rigid bodies and elastic bodies. The launch dynamics model, eigenfrequency equations and dynamics response equations of the MLRS are established using the launch dynamics and transfer matrix method for multibody systems (MSTMM). The corresponding vibration characteristics and dynamics response are simulated, and the simulated results are verified by a series of tests directly, including modal test, pulse thrust test. Then, the simulation system of launch and flight dynamics of the MLRS is developed combining the Monte Carlo simulation technology. The initial disturbance and firing precision are simulated and verified by the live firing test. On above basis, the relationship between the dynamics characteristics and firing precision of the MLRS is analyzed. And then, the test dynamics method of non-full loading firing is proposed for reducing the rocket consumption in firing precision test by optimizing the launch modes of the MLRS. Finally, a seven-shot non-full loading firing test scheme for a practical MLRS is designed. And the correctness of the scheme is proved by practical contrastive firing test. The test results show that the amount of the rockets consumption in firing precision test is reduced by 61% compared with the conventional test method.

The Phoenix Rises

Abstract : The story of how this acquisition rebounded from brink of extinction to a model of reduced-cost and ahead-of-schedule production illustrates how determination, use of integrated product teams, executive officer system, and process approach to manufacturing can produce results. Secretary of Air Force, Dr. Sheila Widnall, used to joke that phrase, the troubled C-17 program was really all one word. Accordingly, there are many accounts describing how C-17 Globemaster III airlifter got into trouble. Surprisingly, no one has tried to capture specifics of even more remarkable story of how C-17 got out of trouble. This article will tell that story. The authors begin with a short description of aircraft and requirement for it. Then, to put ultimate success of this major acquisition in proper context, they provide a brief review of program's troubled past. Following this review, they cover salient events in Pentagon, offices, and McDonnell Douglas plant that substantially contributed to remarkable turnaround. The authors conclude with an in-depth look at lessons learned that could benefit other programs. The C-17 aircraft is U.S. Air Force's effort to develop a modern airlifter capable of meeting worldwide air mobility needs of DoD. In late 1970s, need for an aircraft capable of carrying large payloads to austere fields remained. The aircraft was specifically designed to carry modern combat weapons of U.S. ground forces directly into airfields near conflict. This capability is known as direct delivery. Perhaps most important, C-17 would also provide a way to move outsize cargo (very large equipment like M-1A Abrams tank, or Multiple Launch Rocket System -- equipment that cannot fit on today's C-141s or C-130s) for inter- and intratheater airlift.

Военно-техническое сотрудничество Белоруссии и Китая в ракетной области

Belarus and China maintain extensive economic ties. They are actively cooperating in the field of rocketry too. In 2015 at the military parade in Minsk a multiple launch rocket system “Polonez” was demonstrated for the first time. Belarusian experts and politicians declared the “Polonez” MLRS a Belarusian product but Russian experts presumed China's participation in its development. Later Minsk admitted the Chinese assistance in the development of the “Polonez” but it still remains unclear how significant is the role of China in this project. A number of Russian experts believe that “Polonez” is a MLRS which is produced in Belarus under a Chinese license. Nevertheless Russian experts positively assessed its combat capabilities. In addition to MLRS Belarus and China cooperate in the space sphere.

Design and implementation of an adaptive Kalman filtering for the launcher of multiple launch rocket system

SummaryPractical application for performing an adaptive Kalman filtering with a digital signal processor is studied. A multiple launch rocket system (MLRS) is considered, and an adaptive Kalman filtering is designed for the state estimation of the launcher by using the measured outputs from a fiber optical gyro mounted on the MLRS. The proposed algorithm remains convergent in the presence of noise covariance errors. The performance of the proposed method is demonstrated by simulations and compared with other types of Kalman filtering algorithms. Eventually, an experiment is implemented for the state estimation of the launcher of MLRS using the TMS320F2812 digital signal processor.

Study on simulation and experiment of control for multiple launch rocket system by computed torque method

Poor dispersion characteristics of rockets, due to the orientation of the launcher for multiple launch rocket system (MLRS) departing from that intended, have always restricted the MLRS development for several decades. Orienting control is a key technique to improve the dispersion characteristics of rockets. The purpose of this paper is to propose an orienting control method for launcher of the MLRS in a salvo firing. Because the MLRS is a typical nonlinear system, the major difficulty in designing the orienting controller lies in the nonlinearity. To deal with the nonlinearity, the concept of computed torque control is introduced. The MLRS equation of motion is established using Lagrange method. The inner loop feedforward and the outer loop feedback are adopted to design the controllers for the azimuth and elevation axes of MLRS. By combining the inner and outer control loops together, the PID-computed torque controller is designed. The numerical simulation is implemented to show the control performance, and then, the effectiveness and applicability of the proposed controller are demonstrated by the firing experiment of a salvo of three rockets.

Design and Testing of an Unguided Rocket with Thermobaric Warhead for Multiple Launcher System

Abstract This paper presents the development, testing and evaluation of a new unguided rocket equipped with a thermobaric warhead. The aim of the research was to design the ammunition to be integrated with an existing multiple launch rocket system. This condition introduced limitations of dimensions, mass and mass distribution. The experimental work consisted also in optimisation of the thermobaric composition and configuration. The resulting ammunition was tested for determination of effective range and precision. The destructive effect was evaluated by live firing against non-armoured vehicles and masonry light structures.

Vibration control of uncertain multiple launch rocket system using radial basis function neural network

Abstract Poor dispersion characteristics of rockets due to the vibration of Multiple Launch Rocket System (MLRS) have always restricted the MLRS development for several decades. Vibration control is a key technique to improve the dispersion characteristics of rockets. For a mechanical system such as MLRS, the major difficulty in designing an appropriate control strategy that can achieve the desired vibration control performance is to guarantee the robustness and stability of the control system under the occurrence of uncertainties and nonlinearities. To approach this problem, a computed torque controller integrated with a radial basis function neural network is proposed to achieve the high-precision vibration control for MLRS. In this paper, the vibration response of a computed torque controlled MLRS is described. The azimuth and elevation mechanisms of the MLRS are driven by permanent magnet synchronous motors and supposed to be rigid. First, the dynamic model of motor-mechanism coupling system is established using Lagrange method and field-oriented control theory. Then, in order to deal with the nonlinearities, a computed torque controller is designed to control the vibration of the MLRS when it is firing a salvo of rockets. Furthermore, to compensate for the lumped uncertainty due to parametric variations and un-modeled dynamics in the design of the computed torque controller, a radial basis function neural network estimator is developed to adapt the uncertainty based on Lyapunov stability theory. Finally, the simulated results demonstrate the effectiveness of the proposed control system and show that the proposed controller is robust with regard to the uncertainty.