Annotation: The article gives the analysis results for the servo drives dynamics, obtained from the theoretical calculations and during the development testing of the high power electric drives. Theoretical research was conducted, using the complete mathematical model of the servo drive, which included the equations of the control signal shaping path, electric motor, reducer and load. The equations of the control signal shaping network include only the characteristics of the compensating element in the assumption that all other delays in the transformation path are minimized. The electric motor equations are assumed in the classical form, taking into account the influence of the following main parameters on the motor dynamics: inductance and stator winding resistance, torque and armature reaction coefficients and rotor moment of inertia. Interaction of the motor with the multimass system of the reducer and load is presented in the form of force interaction of two masses – a reduced mass of the rotor and mass of the load through the certain equivalent rigidity of the kinematic chain. To describe the effect of gap in the kinematic connection the special computational trick, which considerably simplifies its mathematical description, is used. Efficiency of the reducer is presented in the form of the internal friction, proportional to the transmitted force. Calculation results with the application of the given mathematical model match well with the results of the full-scale testing of different specimens of servo drives, which makes it possible to use it for the development of new servomechanisms, as well as for the correct flight simulation when testing the aircraft control systems. In particular, based on the frequency response calculations of the closed circuit with the application of the given mathematical model, it is possible to define optimal parameters of the correcting circuit. Reaction on the step action with the various values of circular amplification coefficient in the circuit gives complete information on the stability regions of the closed circuit and influence of various drive parameters on these regions. Based on the conducted theoretical and experimental studies, the basic conclusions and recommendations were obtained and presented, accounting and implementation of which will provide high dynamic characteristics of the newly designed servo drives.

Annotation: The use of servo drives on flying vehicles determines the requirements to their dynamic characteristics. The problems of dynamics of drive with jet motor are not practically covered in publications. The task arises of selection of structure and parameters of devices consisting of several subsystems whose dynamic characteristics must be brought into agreement with each other in optimal way. The purpose of this work is to develop mathematical dependences for calculation of dynamic characteristics. The functional arrangement of the drive is considered consisting of jet motor based on Segner wheel with de Laval nozzle, mechanical transmission, pneumatic distributing device – jet pipe controlled by electromechanical converter. The layout is presented of mechanical segment of servo drive with jet motor with screw-nut transmission. The dynamic model is presented and the algebraic relations to determine natural frequencies of the drive are given. The motion equations of output rod at full composition of load are given. Using Lagrange transformation as applied to ball screw transmission, the expression for reduced mass of output element was derived. The reduced mass of load depends on the jet motor design and exerts basic influence on the drive’s natural frequencies. The evaluation is given of reduced mass change from the jet motor moment of inertia and reducer transmission coefficient. Based on the proposed algorithms, the dynamic characteristics of servo drive were constructed: transient process and amplitude-frequency characteristic. The drive has relatively low pass band, which is explained by the value of reduced mass of load.

Annotation: The basic mathematical relations are considered to construct static characteristics of nozzle-shutter twostage piston pneumatic drive with the working medium – powder combustion products.

Annotation: For monitoring rocket flight and determining accuracy of spacecraft injection into the planned orbit, it is necessary to ensure the reception of telemetry data from the launch vehicle. Telemetry data receiving stations may be located either on land or on shipboard. When the antenna system of such station is placed on shipboard, ship roll and ship drift have the most considerable impact on the antenna guidance accuracy. To ensure the guidance accuracy of the telemetry receiving antenna set, placed on shipboard, the control algorithm was designed. It was offered to use triaxial rotary support with axis of reflector inclination angle to meet the requirements specified. In the article, the connection between kinematic parameters of the antenna rotary support drives and parameters of the space launch vehicle motion were identified, rotation angles of the antenna drives along the three axes were determined, and the law of angular velocity variation along the azimuthal axis, including the maximum feasible angular velocity provided by the azimuthal axis drive, was chosen. Numerical simulation of antenna guidance algorithms that provide stable signal receiving under conditions of ship roll was carried out in the visual development environment of Embarcadero RAD Studio XE6. Several variants for operation of the rotary support drives of the antenna set were chosen for mathematical simulation; disturbing conditions of ship roll and ship drift were analyzed and chosen for ships with small displacement. The simulation validated the designed antenna control algorithm and showed that the requirements for the cinematic parameters of the antenna drives were reduced under conditions of ship roll when the axis of reflector inclination angle was introduced; and accelerometer unit or GPS receiver installed in the antenna structure additionally increased the accuracy of target designation of the antenna and improved its guidance accuracy

Annotation: Contemporary trends in developing space-rocket hardware indicate the increased demand for light and ultra-light rockets. The first trend in developing the up-to-date light and ultra-light rocket hardware includes improving accuracy of cargo delivery to the specified area; the second trend covers the enhancement of energetic properties and the reduction of production and operational costs. Spinning about the longitudinal axis of symmetry may be one of the ways to improve the light and ultra-light rocket hardware in these trends. Spinning significantly increases stability of a moving object and partially evens out the negative impact of external and internal disturbing factors (skewness and eccentricities of propulsion system and control elements, wind). Refusal to use systems that provide stabilization about the longitudinal axis of symmetry leads to reduction in mass of the control system equipment, thus increasing energetic perfection of the rocket hardware. Hence, rotation of the rocket about the longitudinal axis may be caused by the spinning elements on purpose as well as by disturbing impacts in case of control failure in the roll channel. This article considers suggestions on algorithmic realization of light rocket control methods under conditions of rapid rotation about the longitudinal axis for each of the options mentioned above. This article offers control methods for the rocket, rotating about the longitudinal axis, that provide angular stabilization, improve the transient quality, and determine the angle of roll after program stop of rotation about the longitudinal axis.

Annotation: The conceptual engineering solution was examined to increase the unification and interchangeability of components in a vehicle that can regularly transport cargo and be operationally adapted to solving various problems on the surface of different planets. The difference between this engineering solution and the existing designs of planetary roving vehicles was described. The objective is achieved by assembling a selfpropelled modular platform from generic modules that are rigidly joined with each other to create a unified control system and a unified power supply system for the platform. The number of modules is chosen depending on the objective and equipment installed on the platform. Self-propelled modular platform can function as a unified remote-controlled unit with capability to adapt operationally to solving new problems on the surface of various planets. Novelty of the modular vehicle concept lies in creation of the generic vehicle that is capable of being rebuilt depending on the functional task and can be delivered by parts to the site of its direct operation.

Annotation: To support ignition of Taurus LV first stage core structure engine, an oxidizer dividing valve has been developed that ensures minimal hydraulic resistance, opening time and hydraulic impact. The paper considers the valve design, main phases of its ground development testing and basic critical comments on the design made in the process of manufacturing and testing.

Annotation: The article presents briefly the peculiarities of designing and ground development testing of dispensers turn drive system, the system composition and functioning principle are described.

Annotation: Gasars is a new type of porous cast materials manufactured on the basis of metals and their alloys, some types of ceramics. The basis of the process is gas-eutectic conversion in the system metal-hydrogen. The process of investigation and creation of gasars was commenced in 1979 in the National Metallurgical Academy of Ukraine and is currently continued in Ukraine, the USA, China, Japan, South Korea, Poland and others. The gasars production technological process consists in melting the specified material (metal, alloy, ceramics) in hydrogen (or other active gas) atmosphere at a certain pressure. After the melt is saturated with active gas to a certain concentration, the crystallization process begins at which the pore formation process is launched. As the pores growth occurs perpendicular to crystallization front, the orientation of heat withdrawal influences pores location. So, for example, to obtain radial porosity, radial heat withdrawal is required. To obtain various structures, along with directed crystallization process, the pressure in crystallization chamber is an important factor, which drives the gasar morphology. The porous structure of gasars is diverse, there are the gasars with longitudinal, cylindrical, spherical, conical pores. It is possible to alternate the porosity layers and monolithic metal layers. The dimensions of gasars pores are in the limits from 10 μm to 10 mm at total porosity from 7 to 55 (75%). However, there is a possibility to obtain the pores with smaller diameter. The mechanical properties of gasars have a number of advantages as compared with conventional porous materials produced by different methods. Subsequent processing of the gasars does not differ from analogous non-porous materials, which is also an advantage over conventional porous materials. And in case when the diameter of pores is less than 50 μm, the exceedance of mechanical properties of gasars as compared with monolithic materials of the same chemical composition is observed. This is caused by the fact that the pores were formed during crystallization and at the action of pressure on a gasar, local hardening occurs. At present, the gasars have already found application as light and strong structural materials, filters, heat exchangers, dampers, slide bearings, catalyst elements, friction materials, etc. The use of gasars in space hardware will help to considerably reduce the mass of launch vehicle structural elements without worsening strength properties. The possibility of welding and soldering the gasars allows finding their application in the structure of propellant systems, compressed gas and propellants supply systems, creating filtering elements based on the gasars, including propellant spraying and mixing systems.

Annotation: The basic results of the design calculations and mathematical modelling of the control processes in the precision high-speed servo drive are presented, as well as results of experimental studies of the functional mock-up of this servo drive’s movable gears of the throttle and fuel flow regulator of the ILV main engine. Major task of the studies was theoretical and experimental verification of the required static and dynamic accuracy of the servo drive in the process of try-out of the command signals reception from the main engine’s controller. In the phase of development, theoretical study of the linearized servo drive with application of transformations and theorems of Laplace passages to the limit is conducted. Analytical dependences between servo drive circuit parametres, its elements and characteristics of the control signals are obtained. Instrument errors and servostatic elasticity of the servo drive are calculated. Calculation model including the basic nonlinearities of this servo drive is prepared. Mathematical modelling of the control processes is conducted according to the computational model, varying the circuit and design parameters of the electric drive. Results of the theoretical studies were taken as input data for the requirements specification document to develop the executive unit with the electromotor, reduction gear and output shaft position sensor, and the control box. Functional mockups of the executive unit, control box, as well as the computer-controlled technological test console were manufactured on the basis of the requirements specification documents. The required scope of the laboratory-development tests of the functional mock-up of the servo drive was conducted. Results of the conducted activities confirm the achievement of the required accuracies of the servo drive in the laboratory environment.