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 completely reusable aerospace system based on subsonic carrier with the return of the first stages to the starting point

The concept of aerospace system based on air launch from subsonic twin-fuselage aircraft and the rocket launch into orbit is investigated. The scheme of aerospace system trajectory providing a return to the starting point both of the carrier and the first rocket stage with liquid-fuel motors is proposed. It was shown that the use of subsonic carrier as a launching platform of the rocket system increases the payload mass by 1.2% of the rocket segment MTOW as compared to autonomous ground take-off. The comparative analysis of three versions of carrier aircraft and three fuel options at the first rocket stage was carried out. Analysis showed that compared to kerosene variant the hydrogen hypersonic booster makes it possible to significantly increase the payload mass while the launching costs stay the same.

Analysis of properties of inertia regulator of thrust control system of liquid rocket engine

The quality of the flight task of a space rocket system is determined among other things by the accuracy of maintaining and regulating the thrust of the rocket engine. Improving the accuracy and reducing errors in the engine mode control system will reduce the cost of space launches or allow you to put a large payload into orbit. The article presents a mathematical model of a controller with an inertial booster of a liquid-propellant rocket engine, identifies parameters and values that affect its accuracy, and considers measures to reduce static error

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.