JPH021720B2 - - 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 deployable object, the conventional concept is to connect the planar bodies of the deployable object with a hinge that can freely rotate on one axis, and to expand it, like a so-called developable double corrugated surface. In the case of a two-dimensional deployment method in which the device is deployed in two directions during deployment, the conventional method using a hinge that can freely rotate in one axis has the following problems. Fig. 1a shows the unfolded object before it is developed, Fig. 1b shows the unfolded object during its development, and Fig. 1c shows the unfolded object after it is developed. 1a-1d and satellite 2
are connected using hinges 3a to 3e, each of which is rotatable on one axis. When the rotation angle θ ₁ of the parallelogram plane 1a is 90 degrees, it is the state before development shown in Figure 1 a, and when it is 0 degrees, it is the state after development shown in Figure 1 c, and when it is 0 degrees, it is the state after development shown in Figure 1 b. Planar bodies 1a and 1b are connected via a hinge 3b that can freely rotate on one axis when unfolded.
The respective rotation angles θ ₁ and θ ₂ always vary equally, and the same conditions apply to the planar bodies 1b, 1c and the planar body 1.
c and 1d, and the positional relationship of the planar bodies 1a to 1d at the time of development is determined from these conditions. As will be described later, the distance L between the plane bodies 1d and 1a
changes before, during, and after the unfolding of the developable object, so the conventional method of connecting the two planar objects of the developable object with a hinge that can freely rotate on one axis is difficult to achieve smoothly in the case of a two-dimensional unfolding mechanism. It has the disadvantage of not being able to achieve unfolding motion. This invention proposes a deployable object deployment mechanism for a spacecraft that can deal with such problems, and the invention will be explained in detail below using FIG. 2. Figure 2a is a diagram showing a hinge that can rotate freely on one axis, and is a diagram showing a hinge that can rotate freely on one axis, and is
The shape specifications are defined by the plate thickness T of a and 1b, the hinge diameter D, and the hinge clearance H from the hinge rotation center 4a to the end of the plane body. Figure 2b shows three hinges 3a, which can rotate freely on one axis.
3b and 3c are diagrams showing a combined hinge 5, which connects two planar bodies 1a and 1b. FIG. 2c is a diagram showing the proposed deployable object deployment mechanism after deployment, with hinges 3a to 3a rotatable on one axis attached to the satellite 2.
Parallelogram planar bodies 1a to 1i are attached via 3i. Here, hinges 3b, 3 that can freely rotate on one axis
d, 3f, 3h are attached below the plane body, 1
Hinge 3a, 3c, 3e, 3g, 3 that can rotate freely
i is attached above the flat body. Since each planar body unfolds symmetrically via hinges 3a to 3i that are rotatable on one axis, the planar bodies 1a to 1 when unfolded
The positional relationship of i is determined. At this time, the plane body 1a,
Let us find the distance L ₁ between 1f and the distance L ₂ between planar bodies 1d and 1i. FIG. 2d shows the rotation angle θ ₁ formed by the satellite 2 and the first planar body 1a. FIG. 2e shows the rotation angle θ ₂ formed by the third planar body 1c and the fourth planar body 1d.
FIG. 2f shows an angle θ ₃ formed by the first plane body 1a, the second plane body 1b, the fifth plane body 1e, and the sixth plane body 1f. FIG. 2g shows the rotation angle θ ₄ formed by the first planar body 1a and the sixth planar body 1f. In Fig. 2C, axis 6
Let us consider a z-axis (not shown) that constitutes a right-handed coordinate system orthogonal to the a, y-axes 6b, and the above two axes. In the above coordinate system, let us assume that the coordinates of the vertex 7a are (x _c , y _c ,
z _c ) and the coordinates of the intersection 7d between the straight line passing through the vertex 7a and having an inclination perpendicular to the slope of the straight line composed of the vertices 7b and 7c, and the straight line composed of the vertices 7b and 7c, as (x _M , y _M , z _M ), the rotation angle θ ₂
is defined as follows. Here, N indicates the number of stages, that is, the number of plane bodies arranged in the x-axis direction. If the coordinates (x _c , y _c , z _c ) are the coordinates (x _A , y _A , z _A ) of the vertex 7b, they have the following relationship. x _c = x _A y _c = y _A − P ₁ ...(2) z _c = z _A where P ₁ is the length of the side of each planar body in the y-axis direction. The coordinates (x _A , y _A , z _A ) can be written as: Here, H is the hinge clearance, θ is the hinge diameter, P ₂ is the length of the side of each planar body in the x-axis direction, T is the thickness of the planar body, and θ _a is the smaller apex angle of the planar body. Further, if the slope of the straight line connecting the vertices 7b and 7c is α and the slope perpendicular to it is α', they can be expressed as in the following equation. Therefore, the coordinates (x _M , y _M , z _M ) can be expressed by the following equation. From the above, θ ₂ was defined. θ ₃ is defined as follows. θ ₃ = ARCTAN (−α) ... (6) The rotation angle θ ₄ is the coordinate of the vertex 7e (x ₂ , y ₂ , z ₂ ) and the slope of the straight line that passes through the vertex 7e and consists of the vertices 7f and 7g. If the coordinates of the intersection point 7h of a straight line having orthogonal inclinations and a straight line formed from the vertices 7f and 7g are (x _N , y _N , z _N ), it is defined as follows. The coordinates (x ₂ , y ₂ , z ₂ ) are the coordinates (x ₁ ,
y ₁ , z ₁ ) and has the following relationship. x ₂ = x ₁ y ₂ = −y ₁ ...(8) z ₂ = z ₁ where the coordinates (x ₁ , y ₁ , z ₁ ) can be written as follows. x ₁ = H x sin (θ ₁ ) + D/2 x cos (θ ₁ ) Y ₁ = P ₁ /2 ...(9) z ₁ = H x cos (θ ₁ ) - D/2 x sin (θ ₁ ) Furthermore, the coordinates (x _N , y _N , z _N ) can be written as follows. x _N =2y ₁ + (α′−α)×x ₁ /α′−α Y _N =−y ₁ +α′ ₁ (x _N −x ₁ ) z _N =z ₁ +P ₂ sin(θ _a ) cos( θ ₁ )×(x ₁ −x _N ) ² + (Y ₁
−Y _N ) ² / (P ₂ sin (θ _a ) sin (θ ₁ ) ² + (P ₂ cos (θ _a )
) ² or more defined θ ₄ . Here, if the coordinates of vertex 7i are (x _p , y _p ), then L ₁
is expressed by the following equation. L ₁ = (x _P - x ₁ ) ² + (Y _P - y ₁ ) ² ... (11) However, x _p - x ₁ = [2 {D/2cos (θ ₁ ) + H×sin (θ ₁ )} (
N-1)+2Tcos( _θ1 )×N+(-1) ^N -1/2/2
]×{1 −cos(2θ ₃ )}+2[{D/2sin(θ ₂ )+H×cos
(θ ₂ )}+T×1−(−1) ^N /2×sin(θ ₂ )〕×1
/1+α′ ² …(12) Y _p −Y ₁ = [2{D/2cos(θ ₁ )+H×sin(θ ₁ )}(
N-1)+2Tcos( _θ1 )×N+(-1) ^N- 1/2/2×sin( _2θ3 )+2[{D/2sin( _θ2 )+H×cos(
θ ₂ )}+T×1−(−1) ^N /2×sin(θ ₂ )]×α′
/1+α′ ₂ ...(13). L ₂ is the straight line connecting vertices 7j and 7k and the vertex 7l,
Coordinates of the intersection point (x _Q , y _Q ) of a straight line that has an inclination parallel to the straight line connecting 7 m and that passes through the center of the above two straight lines and a straight line that passes through the apex 7 n and has an inclination perpendicular to the above straight line and the apex 7 n Distance to (x _B , y _B ) and point 7d
The distance between the coordinates (x _M , y _M ) of the vertex 7a and the coordinates (x _c , y _c ) of the vertex 7a can be expressed as shown in the following equation. L ₂ = 2×{√( _Q − _B ) ² +( _Q − _B ) ² −√( _M − _c ) ² +( _M − _c ) ² } ……(14) Here x _M −x _c = P ₁ /α′−α …(17) y _M −y _c = α′P ₁ /α′−α …(18). Now H = 2mm, D = 5mm, P ₁ = P ₂ = 100
Table 1 shows the changes in L ₁ and L ₂ corresponding to θ ₁ when θ _a =60°, T=5 mm, and N=3.

[Table] In this way, plane bodies 1a, 1f, plane bodies 1b, 1
e, the distance between the plane bodies 1e and 1h, and the distance between the plane bodies 1d and 1i has a maximum value and a minimum value. By using the hinges 5a to 5d explained in FIG. 2b to connect these, the plane bodies 1a, 1f, plane bodies 1b, 1e, plane bodies 1e, 1h, plane bodies 1d, 1 can also be used during deployment.
i can achieve smooth unfolding movement while being rigidly coupled. FIG. 2 is a diagram showing the proposed deployable object deployment mechanism before deployment, in which planar bodies 1a to 1i are connected to the satellite 2 via hinges 3a to 3i, which are rotatable in one axis, and are rotatable in one axis. The planar bodies are held together by hinges 5a to 5d, which are a combination of a plurality of hinges. Therefore, according to the present invention, it is possible to cope with the variation in the distance between plane bodies that occurs in the case of a two-dimensional unfolding mechanism by using a hinge that is a combination of a plurality of hinges that can freely rotate on one axis, and to smoothly rotate each plane. Symmetric expansion of planar bodies can also be achieved.

[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 according to the conventional concept during expansion, and Figure 1c is a diagram after the expansion of the unfolded object according to the conventional concept. FIG. 2a is a diagram showing a hinge that can freely rotate on one axis, FIG. Figure 2 d to g are views showing the unfolded product according to the invention after development; Figure 2 h is a diagram showing the unfolded product according to the invention before development; 1 is a parallelogram; 2 is a plane body, 2 is a satellite, 3 is a hinge that can rotate on one axis, 4 is the hinge rotation center, 5 is a hinge that is a combination of multiple hinges that can be rotated on one axis, 6 is a coordinate system, and 7 is a parallelogram plane body. Each vertex. 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, each of the planar objects of the deployable object consisting of a plurality of planar objects is on the same plane. Then, the planar bodies of the developed object are connected to each other using a first hinge that is rotatable on one axis and a second hinge that is a combination of a plurality of first hinges that are rotatable on one axis so as to form a predetermined arrangement. A deployable object deploying mechanism for a spacecraft, characterized in that the planar bodies are configured to expand two-dimensionally while maintaining mutual symmetry during the unfolding process due to the action of the first and second hinges.