RU2427949C2 - Transformable umbrella-type antenna of space vehicle - Google Patents

Abstract

FIELD: electricity.

SUBSTANCE: transformable umbrella-type antenna of space vehicle includes power spokes hidden by means of drives and fixed by means of hinges on hub of antenna reflector with their uniform distribution along its perimetre. Each spoke consists at least of two bends connected by means of intermediate hinges. Antenna mirror is made of radio reflecting net fixed on spokes. Antenna is equipped with additional hinges, each of which is provided with rotation axis in spoke opening plane. Connections of spoke hinges to antenna reflector hub are made through the above additional hinges. All antenna hinges are provided with their electric drives; at that, rotation axes of each hinge-electric drive pair coincide; antenna reflector hub like spokes can be made from graphite epoxy.

EFFECT: higher operating reliability, accuracy of antenna alignment during operation and providing the possibility of creating antenna with large diameters.

2 cl, 3 dwg

Description

The invention relates to space technology, in particular to deployable reflectors of space antennas, made on the basis of large-sized rod structures.

Currently, for spacecraft manufactured by ISS OJSC, it is proposed to use umbrella-type antennas with radial profiled spokes, on which a reflective surface of a metal knitted mesh is fixed, as promising large-sized transformable antennas. According to the overall mass characteristics, this design is most suitable for antennas with an aperture of 3-5 m.

At the stage of launching the spacecraft into the target orbit, the antenna is in a folded (transport) configuration. After the device is put into orbit, the antenna is transferred to the open (orbital) configuration. To accomplish this task, the antenna includes a precision positioning mechanism (MPP).

The main component of the MPP, providing the disclosure of the antenna from the starting position to the orbital, is the drive unit. The drive device ensures the fulfillment of the basic requirements for MPP, namely:

- providing the specified parameters for the kinematics and dynamics of the disclosure of the antenna, as well as the alignment of the antenna mirror in ensuring the specified reliability of the operation during its operation in orbit under severe conditions of large temperature differences;

- ensuring the placement of the antenna in the starting position in a given volume of the payload zone of the spacecraft;

- providing the required mass characteristics;

- ensuring the specified reliability of the disclosure of the antenna.

A typical drive arrangement is a spring drive for turning each antenna power spoke.

The main drawback in the development and manufacture of large transformable umbrella type antennas is the problem of synchronizing the disclosure of especially opposed masts or spokes. If one of the opposite masts or spokes is late in opening, and the other, on the contrary, is ahead, then the cable-stayed network supporting the radio-reflecting grid, and the grid itself become entangled about the cable-stayed network with a radio-reflecting grid that did not manage to start opening.

Known antenna for HALCA (AIAA 2003-1629 Optimal Design of Tension Truss Antennas. A.G. Tibert Royal Institute of Technology Stockholm, Sweden) with a hybrid tension truss. Six retractable masts support a five-belt tension truss. To improve the accuracy of the surface, each triangle of the tension truss is divided into nine smaller triangles using a cable-stayed network that supports a radio-reflective grid. The shape of the cable-stayed network is controlled by adjusting braces connected to the rear tension truss (not identical with the upper tension truss).

The disadvantages of this antenna are the complexity, the lack of reliability, the limited capabilities of this solution in creating antennas with large diameters, 24-50 m or more.

A transformable antenna was selected as a prototype (A.V. Ivanov. Choosing a drive device for the precision positioning mechanism of a transformable antenna of a spacecraft. Reshetnev readings: materials of the X International Scientific Conference dedicated to the memory of the general designer of rocket and space systems academician M.F.Reshetnev (8- November 10, 2006, Krasnoyarsk) / Siberian State Aerospace University. - Krasnoyarsk, 2006. - 414 p., Pp. 47 and 48).

A transformable antenna of the umbrella type of a spacecraft (KA) with an aperture (diameter of the opening of the antenna surface) 3-5 m contains: radial profiled spokes (for example, 18 spokes) pivotally mounted on the hub of the antenna reflector, a drive mechanism for opening radial profiled spokes, made in as a mechanism of precision positioning (MPP) using springs as actuators for turning (opening) each antenna spoke.

In the process of launching the spacecraft into the target orbit, the antenna is in a folded configuration, and after the launch of the spacecraft into the target orbit, it is transferred to the open orbital configuration using spring drives.

The disadvantages of this antenna are the low reliability of its operation due to the opening of each spoke with spring drives, each of which must be unfastened (stripped) before opening the antenna and locked (recessed) after opening the antenna, in the absence of the possibility of alignment (adjustment) of the mirror antennas during its operation in variable temperature conditions of outer space, which reduces the accuracy of the antenna, in the limited possibilities of its use for large-sized antennas etrom, e.g., more than 5 m and 50 m (since its construction is made for use odnokolennyh spokes of not more than 2.5 m, otherwise the conditions are not fulfilled its compactness in a folded state during injection spacecraft into orbit).

The objective of the invention is to increase the reliability and accuracy of antennas, including large ones with a diameter of up to 50 m.

The solution to this problem was achieved due to the fact that the transformable antenna of the umbrella type of the spacecraft, containing power spokes that are opened with the help of drives, fixed with hinges on the hub of the antenna reflector with their uniform distribution along its perimeter, each of which consists of at least two knees connected by means of intermediate hinges, an antenna mirror made of a radio-reflecting grid fixed on knitting needles; the joints of the hinges of the spokes with the hub of the antenna reflector are made through newly introduced additional hinges, each of which is made with the axis of rotation in the plane of the opening of the spoke, the axis of the hinge and their drives are made coaxial.

The proposed transformable antenna of the umbrella type is illustrated in figures 1, 2 and 3, in which it is shown, respectively, in the open, folded and half-open positions. The proposed transformable antenna of the umbrella type of the spacecraft contains: power spokes, which are opened by means of drives 1, each of which consists of at least two knees 2 and 3, connected by means of intermediate hinges 4, fixed by hinges 5 on the hub 6 of the antenna reflector with their uniform distribution along its perimeter, the antenna mirror 7 is made of a radio-reflective grid fixed to the needles; the joints of the 5-spoke hinges with the hub 6 of the antenna reflector are made through newly introduced additional hinges 8, each of which is made with a rotation axis in the plane of the spoke opening, all antenna joints are made with their drives 1, and the axis of rotation of each pair of the hinge-drive is coplanar; the hub 6 of the antenna reflector is made of carbon fiber, as are the spokes.

The proposed antenna operates as follows. During the launch of the spacecraft into orbit, the antenna is in a folded state under the fairing of the launch vehicle (figure 2). After putting the SC into orbit, a command is issued to open the antenna, through which a command is sent to the drives 1 of the hinges 4, 5 and 8, the spokes are deployed before the mirror 7 receives the antenna (radio-reflecting grid) of a given parabolic shape (Fig. 3). Typically, large diameter transformed antennas have a mirror alignment system 7 for the antenna so that during operation it meets the specified requirements for the standard deviation of the surface sections from the ideal theoretical surface of the parabola. This system, for example, by scanning (radio, optical, laser, etc.) the surface of the mirror 7 enters data on the real surface of the mirror into the on-board computer, which determines the areas with deviations in excess of their position from the given ones, after which a command is generated and issued to the nearest drive of the knuckle of the knitting needle in order to eliminate unacceptable deviations of the surface portion of the mirror 7. The antenna alignment system works with a given frequency of monitoring the surface of the mirror 7 of the antenna or any other signal deviation operation of the antenna from the desired accuracy of its operation.

The introduction of additional hinges 8 with drives 1 made it possible to provide additional regulation of the position of each spoke individually and together in directions orthogonal to the axis of the reflector, and thereby increase the degree of accuracy of regulation.

Since the accuracy of tuning the surface of the antenna mirror is influenced by outer space factors, for example, sharp temperature changes in the range of ± 150 ° C, to increase the accuracy of tuning the mirror 7 of the antenna, its additional adjustment is carried out using a cable-stayed system of braces (not shown in the drawings), debugging which, taking into account the elasticity of the radio-reflecting grid of the mirror 7, is carried out in the manufacture of the antenna.

The hub of the reflector 6 of the antenna is made of carbon fiber, as are the spokes. This allowed us to reduce the influence of negative factors in outer space, including in the spacecraft orbital launch site with large overloads, while ensuring the given accuracy of the antenna mirror alignment and its accuracy by selecting material with improved thermal and mass characteristics (carbon fiber).

Thus, due to the fact that the joints of the 5-spoke hinges with the hub 6 of the antenna reflector are made through newly introduced additional hinges 8, each of which is made with a rotation axis in the plane of the opening of the spoke, all antenna joints are made with their own drives, and the rotation axis of each pair the hinge drive coincide, the hub 6 of the antenna reflector is made of carbon fiber, like the spokes, an increase in the reliability of the antenna, an increase in the accuracy of alignment of the antenna during operation, the possibility of creating th antennas with large diameters.

The proposed antenna is considered as an alternative option for the design of promising spacecraft antennas developed by the enterprise.

Of the sources of information and patent materials known to the authors, the totality of features similar to the totality of features of the claimed solution is not known.

Claims (2)

1. Transformable antenna of the umbrella type of the spacecraft, containing power spokes opening with the help of drives, fixed with hinges on the hub of the antenna reflector with their uniform distribution along its perimeter, each of which consists of at least two knees connected by intermediate hinges, an antenna mirror made of a radio-reflective grid fixed to the needles, characterized in that the joints of the hinges of the spokes with the hub of the antenna reflector are made through newly introduced ell hinges, each of which is made with an axis of rotation in the plane of the opening of the spokes, all hinges of the antenna are made with their own electric drives, and the axis of rotation of each pair of hinge - electric drive coincide. 2. The device according to claim 1, characterized in that the hub of the antenna reflector is made of carbon fiber, as are the spokes.

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