Amongst the large-sized transformable space antennas, the most attention is currently paid to developing of antennas with hoop-shaped reflectors. The developers are faced with the necessity of looking for optimal design concepts. This paper shows the various concepts of building of the reflectors of the cable-rod scheme, containing a circular load-bearing framework (load-bearing rim) with a deployment drive set on it and the reflecting surface shape-generating structure, assembled into a single construction by the cable and rod elements. The difference between the proposed design concepts of the reflectors is the various structures of the controllable unfolding mechanisms. In the first alternative of the reflector structure, the unfolding process is supported by the cable, which restrains relative displacements of the tips of the initially compressed springs. The second alternative supposes the cable not to be the restraining element, but an active unit of the unfolding mechanism. This paper also describes various alternatives for connection between tension tie cables and the load-bearing rim. It is shown that the alternative of connection of the tension tie cables to the middles of the load-bearing rim edges allows to perform stress analysis of the structure elements and to obtain required characteristics of the spring drive. The numerical calculations for optimal angular position of the deployment drive pulleys holder relative to the sections of the load-bearing rim for the second alternative of the reflector design, which provides the most force effect on shape-generating structure of the reflector, when the knitted mesh fabric is being pulled, are under consideration in this article. The calculations are confirmed by experimental investigations.

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This paper presents the surface shaping numerical investigations results of truss space constructions mesh reflectors, such as antennas and calibration and adjustment satellites. Shape-generating structure of mentioned constructions adds up to set of triangular facets, made in the form of spatio-curvilinear bar frames, bearing reflecting knitted mesh fabric pulled on it. This work proposes the algorithm of calculation of step-by-step reflecting mesh pulling on the bearing frame’s bars process, using finite elements method. Numerical execution of the developed algorithm involves for resolving the linear elasticity theory first-type boundary value problem, which implies integration of elastic body equilibrium equations without taking into account mass forces when kinematic boundary conditions are given. Analyzing when having done numerical calculations, it's possible to determine what grade obtained shapes of reflecting surfaces are precise with, and to find possible for developing variants of the antenna structure, which would allow to obtain the reflector surface shape with required accuracy by using flexible cables as a part of shape-generating structure. Comparing results of numerical investigations with experimental data received using full-scaled model of spherical calibration and adjustment satellite shows satisfactory qualitative and quantitative matching of both results.