Annotation: Being a final executive element of rocket control systems, a hydraulic actuator is at the same time the main source of various non-linear dependencies in rocket dynamic design whose availability dramatically com plicates theoretical analysis of their dynamics and control systems synthesis. The required accuracy and complexity of mathematical models of hydraulic servo mechanisms are different for different design phases of guided rockets. The paper deals with the simplest models of hydraulic servo actuators intended to calculate rocket controllability and to define requirements to response and power characteristics of the actuators. To calculate the rocket stability regions and to evaluate own stability of servo actuators, a linearized mathematical model of hydraulic servo actuator is used that takes into account the most important parameters having impact on stability of the servo actuator itself and on that of the rocket: hardness of working fluid, stiffness of elastic suspension of the actuator and control element, slope of mechanical characteristic of the actuator in the area of small control signals, which, as full mathematical model analysis showed, is conditioned only by dimensions of initial axial clearances of slide’s throats. The full mathematical model constructed based on accurate calculations of the balance of fluid flow rate through the slide’s throats allows, as early as at designing phase, determining the values of most important static and dynamic characteristics of a future hydraulic actuator, selecting optimal characteristics of slides based on specified degree of stability and response of servo actuator and conducting final modeling of rocket flight on the integrated control system test benches without using real actuators and loading stands. It is correct and universal for all phases of rockets and their control systems designing and testing. Using this mathematical model, the powerful actuators of a line of intercontinental ballistic missiles with swinging reentry vehicle and the main engines actuators of Zenit launch vehicle first stage were developed. The results of their testing separately and in rockets practically fully comply with the data of theoretical calculations.

Annotation: Mission control of the orbital space plane is one of the actual and complicated applied problems of the theory of mobile objects control. Dynamic configuration of this plane as an object of control is described by the system of non-linear differential equations of higher order. Research of stability of such system is a difficult problem. However, thanks to known theorems of Lyapunov, often stability of the real system can be estimated by the roots of the characteristic equation of the linearized system. Thereupon the stability analysis in the linear setting is the necessary link in the process of orbital space plane control system development. Among the methods of synthesis of the automatic control linear systems developed to date one can emphasize the trend, which has become widely-spread in the engineering area. According to this trend the issues of synthesis of the dynamic regulator, observability and controllability for the orbital space plane are considered. Procedure of selection of the dynamic regulator parameters at the early phase of development of the control system for the orbital space plane motion about the center of mass is suggested. Observability and controllability of the orbital space plane are considered. It is shown that the considered control system of the orbital space plane is observable and controllable, i.e. it is possible to develop the stable dynamic regulator, which provides the required speed and accuracy of the angular position of the orbital space plane during the orbital flight. Factors selection procedure is offered for the factors being the part of the control laws for the control system actuators.