JPH025640B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a mechanism for deploying deployable objects of a spacecraft, such as antennas and solar battery panels, which are folded at the time of launch and are deployed at the time of entering or in a predetermined orbit. When unfolding a folded unfolded object, the conventional concept is to connect the flat bodies of the unfolded object with a hinge that can rotate freely on one axis.
1b shows the state before development, FIG. 1b shows the state during development, and FIG. 1c shows the state after development.
Hinge 2a~2 that can rotate ~1d by one axis, respectively
In the case of the secondary deployment method, which is connected to satellite 3 by e and expands in two directions 4a and 4b when deployed like a loosely expandable double corrugation surface, a hinge that can rotate freely on one axis is used. The conventional method used has the following problems. In other words, FIG. 2a shows the configuration of a hinge that can freely rotate on one axis. Planar bodies 1a and 1b of plate thickness T are rotatable on one axis with a diameter D and a clearance H between the hinge rotation center 5 and the end of the plane body. It shows a hinge.
FIG. 2b is a diagram illustrating the variation in the distance between plane bodies when unfolded when a uniaxially rotatable hinge is used.
d and the satellite 3 are connected by hinges 2a to 2d that can rotate freely on one axis, and the length of the side of each plane is P1, and the apex angle of the smaller one is θa, then the opposing plane 1a,
We will describe how the distance L1 between 1d changes during development. Figure 2c is a diagram explaining the deployment angle θ ₁ 6a between the plane body 1a and the satellite 3. When the deployment angle θ ₁ is 0°, it is before deployment, and when the deployment angle θ ₁ is 90°, it is after deployment. It is. Now, when the planar body 1a is unfolded in FIG.
and expand symmetrically. Similarly, the planar bodies 1c, 1
Since the development position of d is determined, the flat body 1 is automatically
The distance L1 between a and 1d is determined. Now (X, Y, Z) coordinate system is X axis 7
a, the Y axis 7b and the X axis, and the Y axis and the Z axis constituting the right-handed orthogonal coordinate system, the
The inclination α of the straight line projected in the straight line X-Y plane connecting the vertices 8a and 8b is determined by the following equation. α=-cos(θa)/sin(θa)×sin( _θ1 )...(1) The slope α' of a straight line perpendicular to the above straight line is expressed by the following equation. α'=-1/α ...(2) Also, passing through the midpoint of vertices 8a and 8c of the plane body,
A straight line perpendicular to the straight line connecting the two vertices above and vertex 8
The intersection angle θ ₃ 6b formed by the straight line connecting d and 8a is expressed by the following equation. θ ₃ =ARCTAN(−α) (3) At this time, the coordinates X5, Y5, and Z5 of the vertex 8a are defined by the following equation. FIG. 2d shows the shapes of the second planar body 1b and the third planar body 1c in a straight line that passes through the vertex 8e and is perpendicular to the straight line connecting the vertices 8a and 8b. Two points 8f, 8 on opposing planar bodies 1b, 1c
Coordinates of g (XM, YM, ZM), (XMM, YMM)
The rotation angle θ ₂ 6c formed by the planar body 1b can be expressed as shown in the following equations. however It is Using these, the coordinates of vertices 8h and 8d (X1
3, Y13, Z13) and (X3, Y3, Z3) can be expressed as shown in the following equations. Since the distance L1 between the opposing planar bodies 1a and 1d is the distance between the vertices 8h and 8d, L1 can be found as follows. L1=√(3−13) ² +(3−13) ² +
(3-13) ² ...(7) Now H = 2mm, D = 5mm, P1 = 100mm, θa =
Table 1 shows the relationship between the development angle θ ₁ and the distance L1 when the angle is 60° and T=5 mm.

[Table] As explained above, in the conventional method of connecting the planar bodies of the deployable objects with hinges that can rotate freely on one axis, in the case of a deployment mechanism that deploys two-dimensionally, the distance between the planar bodies changes during deployment. Therefore, it has the disadvantage that smooth unfolding movement cannot be achieved. This invention proposes a deployable object deployment mechanism for a spacecraft that can deal with such problems, and this invention will be explained in detail below using FIG. 3. Figure 3a shows three hinges 2a that can rotate on one axis,
It is a figure showing the hinge 9 which combined 2b and 2c, and is connected to two plane bodies 1a and 1b.
As a result, the shaft length can be changed and the shaft can be freely rotated on one axis. Third
FIG. b is a diagram showing the state before deployment, in which the satellite 3 and the planar bodies 1a to 1d are connected by hinges 2a to 2d that are rotatable in one axis and a hinge 9 that is variable in axis length and rotatable in one axis. Figure 3c is a diagram showing the satellite 3 after deployment.
The planar bodies 1a to 1d are connected by hinges 2a to 2d that are rotatable on one axis and a hinge 9 that has a variable axial length and is rotatable on one axis. Therefore, according to the present invention, it is possible to absorb changes in the distance between plane bodies that occur in the case of a two-dimensional unfolding mechanism, and achieve smooth unfolding motion. It can also absorb distortions such as thermal deformation that occur in outer space.

[Brief explanation of drawings]

Figure 1a is a diagram showing the unfolded object before development according to the conventional concept, Figure 1b is a diagram showing the unfolded object in the middle of expansion according to the conventional concept, and Figure 1c is after the expansion of the unfolded object according to the conventional concept. Figure 2a is a diagram showing a conventional concept of a uniaxially rotatable hinge, and Figure 2b is a diagram showing changes in the distance between planar bodies during deployment when a uniaxially rotatable hinge is used. Figure 2c is a diagram explaining the deployment angle between the flat body and the satellite.
Fig. 2 d is a diagram illustrating the unfolding angle of a planar body, Fig. 3 a is a diagram showing a hinge that is variable in axis length and rotatable on one axis according to the present invention, and Fig. 3 b is a diagram before unfolding of the deployable object according to the present invention. FIG. 3c is a diagram showing the deployable product according to the present invention after it is deployed, where 1 is a planar body, 2 is a hinge that can freely rotate on one axis, 3 is a satellite, 4 is a deployment direction, and 5 is a hinge rotation. The center, 6 is the rotation angle, 7 is the coordinate system, 8 is the position of the planar body, and 9 is a hinge whose axial length is variable and can be freely rotated on one axis. In addition, the same reference numerals are given to the same or corresponding parts in the figures.

Claims (1)

[Claims] 1. In a deployable object deployment mechanism of a spacecraft configured to deploy deployable objects attached to a spacecraft two-dimensionally in outer space, a single axis is used between the flat bodies of the deployable object consisting of a plurality of flat bodies. By using a rotatable first hinge and a second hinge that is a combination of a plurality of uniaxially rotatable first hinges, the distance between the plane bodies that occurs when the above-mentioned expandable object is expanded two-dimensionally can be reduced. A deployable object deployment mechanism for a spacecraft, characterized in that a smooth deploying movement of the deployable object can be achieved by absorbing fluctuations in the amount by the second hinge.