In the article experimental survey results of planetary roller screw drive for usage in high precision parallel structure mechanisms for space application are considered. The drive was developed in Academician M.F. Reshetnev Information Satellite System. Roller screw is perspective type of precision linear drives which excels in several characteristics extensively used in modern time ball screws. Ground tests conducting methodology, tests scheme of the developed roller screw are described. Key parameters of analyzed precision linear drive such as: transmission accuracy, repeatability, axial stiffness and operating lifetime are presented.

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The problems of designing a hexapod control system - a mechanism with parallel kinematics, designed for guidance and positioning of instruments and antennas of orbiting satellite platforms are considered. Based on the solution of the extended kinematics problem, the algorithm for controlling linear drives with a kinematic pair of screw-nut and two two-axis hinges is specified. The hexapod control scheme with the spatial load position sensor is given, the feasibility of positional control algorithms is estimated on the basis of the modern domestic element base. The estimation is made by the method of mathematical modeling. An algorithm for adaptive neural network control of a hexapod is proposed. An artificial neural network has been developed, which together with a nonlinear controller regulates the force acting on linear actuators by control error. To assess the quality of hexapod control, a dynamic model of the hexapod control system was created in the simulation package SimMechanics of the MATLAB Simulink system. A description is given of the hardware part of the digital control system-the hexapod control unit).

A large-sized transformable space-based reflector has been reviewed. Features of this design are compactness in transportation, a large ratio of volumes in the opened and folded states, low mass with substantial dimensions. Given these properties, there are some problems with reliable deployment of this system, with maintaining and regulating the required form of the radio-reflective net fabric. In this paper we demonstrate the application of the mechanics of flexible thread to find the shape and force of the pull in the space-based cable-stayed reflectors. Equations showing the dependence of the form of the net fabric on the tension force in a single have been obtained. A particular problem is considered for finding the tension force at a given position of the net fabric. There have been obtained appropriate solutions for three points, two rigidly fixed and adjustable, located between them. This approach is applicable for determining the tension force in the case of using different materials and different initial conditions.