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The purpose of this paper is to present some aspects regarding the calculus model and technical solutions for small multistage launcher for used testing the spatial equipment and scientific measurements. The calculus model consists in numerical simulation of launcher evolution for different start conditions. The launcher model presented will be with six degrees of freedom (6DOF) with dynamical translational equations written in quasi-velocity frame. Model includes aerodynamics terms in polynomial form, the thrust terms and guidance relations all of this adapted for the 6 DOF model. The results analysed will be the flight parameters and ballistic performances. The discussions area will focus around the technical possibility to realize this small multi-stage launcher, by using hybrid engine technology for uppers stage including for Reaction Control System. [ABSTRACT FROM AUTHOR]

Abstract: This study is concerned with the coordinated control problem for regulation/protection mode-switching of a ducted rocket, in order to obtain the maximum system performance while ensuring safety. The proposed strategy has an inner/outer loop control structure which decomposes the contradiction between performance and safety into two modes of regulation and protection. Specifically, first, the mathematical model including the actuator (gas regulating system) and the plant (ducted rocket engine) is introduced. Second, taking the inlet buzz for instance, the ducted rocket coordinated control problem for thrust regulation and inlet buzz limit protection is formulated and discussed. Third, to solve the problem, based on the main inner loop, a limit protection controller (outer loop) design method is developed utilizing a linear quadratic optimal control technique, and a coordinated control logic is then presented. At last, the whole coordinated control strategy is applied to the ducted rocket control model, and simulation results demonstrate its effectiveness. [Copyright &y& Elsevier]

In this article, a project of on-board control system with fuzzy efficiency of air-task estimation subsystem for UCAV rockets is presented. Moreover, some features allowing the use of fuzzy logic subsystems in unmanned aviation will be described as well. Complexity of the project and some mathematical calculations required relevant assumptions which are also reported. Finally, prognosis about operation of the system and conclusions are provided. This article is an integral part of authors’ scientific research. [ABSTRACT FROM AUTHOR]

The Space Systems Laboratory at Kyushu Institute of Technology is developing a fully reusable sounding rocket named WIRES (WInged REusable Sounding rocket). The winged rocket incorporates many novel technologies, including a full composite structure and a navigation, guidance, and control system. It is also equipped with an innovative hybrid rocket engine named CAMUI (CAscaded MUltistage Impinging-jet). In such a complex rocket, system integration is difficult to achieve and innovation is imperative. The laboratory is therefore also developing a subscale model of the rocket named WIRES#014 to assess the new navigation, guidance, and control system. This paper describes the procedure and results of a trial and error approach, comprising three ground combustion tests, to integrating the systems of the rocket. In the first and second try of the combustion test, the tests had some troubles mainly about ground support system and avionics. Authors eliminated these errors after the cause analysis; the third combustion test was finally succeeded. [ABSTRACT FROM AUTHOR]

This paper is dedicated to on-board terminal control systems. Specific features of this class of systems are identified and an approach to terminal feedback control synthesis is proposed, being adequate to the nature of terminal problems. Theoretical and practical problems in on-board terminal systems design for liquid-propellant carrier rockets are discussed. The establishment and further development of research in the field of fuel consumption control systems under the supervision of Academician B.N. Petrov for liquid-propellant carrier rockets (from R-7 rocket till modern carrier vehicles) are considered. [ABSTRACT FROM AUTHOR]

Long- and medium-range artillery rockets are used for indirect fire on distant targets. As they have a large impact-point dispersion, they are considered to be area weapons. Nevertheless, a control system is required in order to reduce the dispersion and increase hit probability. The pulse-jet control system is simple and efficient enough to produce acceptable impact-point dispersion. However, it is necessary to perform an optimization of the control logic in order to obtain a satisfactory performance with the minimum number and intensity of control pulses. A new two-phase guidance scheme named trajectory tracking with pulse-frequency modulation is presented, considering the fact that an artillery rocket flies through different atmospheric environments. Simulation studies have been conducted in order to perform parametric and performance analyses. It is shown that the presented guidance scheme achieves excellent accuracy even in the case of a small number of pulse jets. In the case of a large number, it tends to nullify the impact-point dispersion. It is also shown that in comparison with the window-based trajectory-tracking guidance, the proposed method achieves significantly better results. [ABSTRACT FROM AUTHOR]

To improve firing dispersion of Multiple Launch Rocket System (MLRS), the launching dynamic model of MLRS and the simulation system of firing dispersion of MLRS were established by using transfer matrix method of multibody system. The simulation results were validated by the modal test results of the vibration characteristic for MLRS. The vibration characteristic, dynamics response and firing dispersion of MLRS under different firing environments were simulated, and the influencs of firing dispersion of MLRS with different firing orders and firing intervals was researched, the optimal firing orders and firing intervals for improving firing dispersion of MLRS was obtained. A smaller firing device with variable firing orders and intervals for MLRS were designed and actualized, and the firing technology with higher firing dispersion of MLRS by the optimal firing orders and firing intervals could be realized. In some firing dispersion test, the firing dispersion of MLRS is improved over twenty percent by using the firing technology. [ABSTRACT FROM AUTHOR]

Certain problems arising in operation of pressure sensors used in rockets and aircrafts are considered. The role and position of thin-film tensoresistive pressure sensors (PRPS) are discussed; these sensors are based on thin-film nano-and microelectromechanical systems. The basic research directions in the field of PRPS are analyzed and presented. The relevance of solving the problem to improve the accuracy and performance characteristics of the sensors and sensing devices (to the level of best-in-class products) is shown; certain ways to solve it are proposed. The basic research directions in the field of PRPS are identified allowing to design the pressure sensors being stable to external influence of nonstationary temperatures and increased vibroaccelerations. [ABSTRACT FROM AUTHOR]

Presented were the main results of improving the principles and algorithms of the onboard control systems of the objects of rocket-and-space technology in the normal and abnormal conditions of flight service. [ABSTRACT FROM AUTHOR]

The control system design and experimental investigation of the gas regulating system for a ducted rocket are studied in this article. First, the dynamic model of the gas regulating system for the ducted rocket was established, and comparison of the two regulating modes regarding non-linearity and uncertainty was done. In contrast with the area-regulated mode, the non-linearity of the pressure-balanced mode is smaller and the robustness is stronger. Then, the study of the the gas control system is performed based on the model established in this article. The introduction of high-gain feedback suppresses the effects of non-linearity and uncertainty in the pneumatic servo system. Also, a proportional-integral controller for the gas regulating system based on linear matrix inequality is designed. Lastly, an experimental investigation of the gas flow control system is done to verify the validity of the gas control system. The experimental result shows that the gas flow control system has good performance. The turndown ratio of mass flow through the control valve was up to 3.7:1. [ABSTRACT FROM AUTHOR]

An attitude determination and in-flight calibration extended Kalman filter and the corresponding smoother have been developed to estimate three-axis attitude of spinning sounding rockets. The attitude determination system uses low-accuracy commercial microelectromechanical system rate gyros, coupled with a three-axis magnetometer and a one-axis sun sensor. Because only postflight analysis is necessary, the improved performance of a smoother is used in the attitude reconstruction because postflight computation allows the use of a noncausal algorithm. Gyro misalignment and scale-factor errors are proportional to the angular rate, and spin-stabilized rockets without a despin unit usually have a large angular velocity in the range of 4-6 cycles per second about the spin axis. Therefore, gyro misalignment and scale-factor errors can have a significant effect on the attitude propagation, which is based on the gyro measurements. In this work, in-flight calibration is carried out, estimating sensor relative misalignments in addition to bias and scale-factor errors. To ensure filter convergence, an initialization algorithm suitable for producing an initial attitude estimate from a vector measurement and a scalar measurement has been developed. The initialization algorithm uses an attitude representation based on the minimum quaternion combined with a search method. The filter and smoother have been tested using a truth-model simulation, and the accuracy is shown to be dependent on the rocket motion. A rich motion time history makes the parameters more observable and thereby the estimates more accurate. Simulation results indicate that an attitude accuracy on the order of 0.5-1 degrees (3 sigma) can be achieved with a low-cost suite of sensors. [ABSTRACT FROM AUTHOR]

The simple, ballistic time-of-flight equation for the maximum altitude of a vertically launched rocket neglects the effects of atmospheric drag. We show that the error introduced by using this equation to estimate the maximum altitude is typically less than 1% because of the effective cancellations of timing errors during the ascent and descent of the rocket. [ABSTRACT FROM AUTHOR]

Regeneratively cooled nozzle structures of Reusable Launch Vehicles (RLV) belong to the most critical components of a space shuttle main engine. The so-called doghouse effect is a failure mode in the rocket combustion chamber wall, which has been observed experimentally. Within the Collaborative Research Centre SFB-TR 40 of the German Research Foundation (DFG), new technologies for the future space-transport-systems are being developed. By using a new continuum mechanical approach, motivated by a rheological model, we are able to reproduce the doghouse effect. Moreover we intend to give reliable lifetime predictions for rocket combustion chamber structures so that in future components can be tested virtually instead of conducting real experiments. (© 2014 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

This article reports that a conference on the control theory in memory of Academician Boris Nikolaevich Petrov, was held at the Trapeznikov Institute of Control Sciences, Russian Academy of Sciences in Moscow, Russia. At the morning session, presented were the papers "Life and Work of Academician B.N. Petrov" by Yu.P. Portnov-Sokolov and V.Yu Rutkovskii and "Academician B.N. Petrov and Rocket-and-Space Technology" by N.A. Anfimov. Petrov collaborated with S.P. Korolev since the 1950's. He undertook the responsibility for the philosophy of the terminal systems for control of fuel consumption of the liquid-propellant rocket engines and adaptive control systems for some classes of rockets of the principal designer I.S. Seleznev. The third session discussed a construction procedure and algorithms of digital processing for the on-board systems of control of fuel-tank pressurization of liquid-propellant rockets.