Reflector deployment techniques for satellites
View Patent ↗A high capacity satellite having a launch configuration in which one or more antenna reflectors may be stored forward of a forward surface of the spacecraft and an on-orbit configuration in which a reflector boom may be rotated to displace the one or more antenna reflectors a substantial distance from the main body in the yaw axis direction and in a direction orthogonal to the yaw axis direction.
1. A spacecraft, the spacecraft being reconfigurable between a launch configuration and an on-orbit configuration, the spacecraft comprising:
a forward surface and an aft surface, each substantially orthogonal to the spacecraft yaw axis;
a main body disposed between the forward surface and the aft surface;
a first rigid antenna reflector, the first rigid antenna reflector coupled with a first positioning mechanism and associated with a first antenna feed, the first antenna feed configured to illuminate the first rigid antenna reflector when the spacecraft is in the on-orbit configuration; and
a first reflector boom with a first proximal end and a first distal end, the first proximal end coupled with the main body via a first pivot mechanism and the first distal end coupled with the first rigid antenna reflector via the first positioning mechanism, wherein:
the first reflector boom is configured to rotate about a rotational axis of the first pivot mechanism,
in the launch configuration, the aperture plane of the first rigid antenna reflector is substantially normal to the rotational axis of the first pivot mechanism, and a substantial portion of the first rigid antenna reflector is forward of the forward surface and inboard of a side of the main body, and
in the on-orbit configuration, the first reflector boom is at a substantial angle with respect to the main body, the aperture plane of the first rigid antenna reflector is substantially parallel to the rotational axis of the first pivot, the first rigid antenna reflector is illuminated by the first antenna feed, and the first rigid antenna reflector is displaced a substantial distance from the main body in the yaw axis direction and in a direction orthogonal to the yaw axis direction.
2. The spacecraft of claim 1 , wherein the first positioning mechanism is configured to rotate the first antenna reflector relative to the first reflector boom.
3. The spacecraft of claim 1 , wherein, in the launch configuration, the first reflector boom is substantially proximate to and substantially parallel to the main body.
4. The spacecraft of claim 1 , wherein, in the launch configuration, the aperture plane of the first rigid antenna reflector is substantially normal to the rotational axis of the first pivot mechanism.
5. The spacecraft of claim 1 , further comprising:
a second rigid antenna reflector, the second rigid antenna reflector coupled with a second positioning mechanism and associated with a second antenna feed, the second antenna feed configured to illuminate the second rigid antenna reflector when the spacecraft is in the on-orbit configuration; and
a second reflector boom with a second proximal end and a second distal end, the second proximal end coupled with the main body via a second pivot mechanism and substantially opposite of the first pivot and the second distal end coupled with the second rigid antenna reflector via the second positioning mechanism, wherein:
the second reflector boom is configured to rotate about a rotational axis of the second pivot mechanism,
in the launch configuration, the aperture plane of the second rigid antenna reflector is substantially normal to the rotational axis of the second pivot mechanism, and a substantial portion of the second rigid antenna reflector is forward of the forward surface and inboard of a side of the main body, and
in the on-orbit configuration, the second reflector boom is at a substantial angle with respect to the main body, the aperture plane of the second rigid antenna reflector is substantially parallel to the rotational axis of the second pivot, the second rigid antenna reflector is illuminated by the second antenna feed, and the second rigid antenna reflector is displaced a substantial distance from the main body in the yaw axis direction and in a direction orthogonal to the yaw axis direction.
6. The spacecraft of claim 5 , comprising:
a third rigid antenna reflector, the third rigid antenna reflector coupled with a third positioning mechanism and associated with a third antenna feed configured to illuminate the third rigid antenna reflector when the spacecraft is in the on-orbit configuration, wherein the third rigid antenna reflector is coupled with the first distal end via the third positioning mechanism; and
a fourth rigid antenna reflector, the fourth rigid antenna reflector coupled with a fourth positioning mechanism and associated with a fourth antenna feed configured to illuminate the fourth rigid antenna reflector when the spacecraft is in the on-orbit configuration, wherein the fourth rigid antenna reflector is coupled with the second distal end via the fourth positioning mechanism, wherein:
in the launch configuration, the aperture planes of the third rigid antenna reflector and the fourth rigid antenna reflector are substantially normal to the rotational axes of the first pivot mechanism and the second pivot mechanism,
repspectively, and a substantial portion of the third rigid antenna reflector and a substantial portion of the fourth rigid antenna reflector are forward of the forward surface and inboard of a side of the main body, and
in the on-orbit configuration, the aperture planes of the third rigid antenna reflector and the fourth rigid antenna reflector are substantially parallel to the rotational axes of the first pivot mechanism and the second pivot mechanism, respectively, the third rigid antenna reflector is illuminated by the third antenna feed, the fourth rigid antenna reflector is illuminated by the fourth antenna feed, and the third rigid antenna reflector and the fourth rigid antenna reflector are displaced a substantial distance from the main body in the yaw axis direction and in directions orthogonal to the yaw axis direction.
7. The spacecraft of claim 6 , further comprising:
a first crossboom, the first crossboom connected with the first positioning mechanism at a first end of the first crossboom, the first crossboom connected with the third positioning mechanism at a second end of the first crossboom, and the first crossboom connected with the first distal end between the first end and the second end of the first crossboom, wherein the first rigid antenna reflector and the third rigid antenna reflector are coupled with the first distal end via the first crossboom; and
a second crossboom, the second crossboom connected with the second positioning mechanism at a first end of the second crossboom, the second crossboom connected with the fourth positioning mechanism at a second end of the second crossboom, and the second crossboom connected with the second distal end between the first end and the second end of the second crossboom, wherein the second rigid antenna reflector and the fourth rigid antenna reflector are coupled with the second distal end via the second crossboom.
8. The spacecraft of claim 1 , wherein the first positioning mechanism is configured to provide dual-axis rotation.
9. The spacecraft of claim 1 , wherein:
in the launch configuration, the first rigid antenna reflector is forward of the first antenna feed, and
in the on-orbit configuration, the first rigid antenna reflector is aft of the first antenna feed.
10. The spacecraft of claim 1 , further comprising:
a first stiffener strut, wherein a first end of the first stiffener strut is coupled with the first reflector boom between the first distal end and the first proximal end and a second end of the first stiffener strut is coupled with the main body at a location other than where the first pivot is connected.
11. The spacecraft of claim 10 ,
wherein the first stiffener strut is selected from the group consisting of a bifold strut, a sliding strut with the first or second end slidably connected with a fixed pivot on the first reflector boom or the main body, respectively, and a fixed strut with the first or second end coupled with a sliding pivot on the first reflector boom or the main body, respectively.
12. The spacecraft of claim 1 , wherein, in the launch configuration, the first distal end extends forward of the forward surface.
13. The spacecraft of claim 1 , wherein the aft surface includes a launch vehicle mating interface, and wherein the spacecraft is configured to orient the forward surface in the nadir direction in the on-orbit configuration.
14. The spacecraft of claim 1 , wherein the aft surface comprises a launch vehicle mating interface, and wherein the spacecraft is configured to orient the aft surface in the nadir direction in the on-orbit configuration.
15. The spacecraft of claim 1 , wherein the spacecraft is configured to orient the first pivot mechanism and the first reflector boom west in the on-orbit configuration.
16. The spacecraft of claim 10 , wherein the first reflector boom includes a first hinge located between the first distal end and the first proximal end, wherein
an outboard portion of the first reflector boom is rotatable about the first hinge rotational axis with respect to an inboard portion of the first reflector boom,
in the launch configuration, the outboard portion of the first reflector boom between the first distal end and the first hinge forms an acute angle with respect to the inboard portion of the first reflector boom between the first proximal end and the first hinge, and
in the on-orbit configuration, the outboard portion of the first reflector boom forms an angle substantially greater than 90 ° with respect to the inboard portion of the first reflector boom and at least a substantial portion of the outboard portion is forward of the forward surface.
17. The spacecraft of claim 5 , further comprising:
a third rigid antenna reflector, the third rigid antenna reflector coupled with a third positioning mechanism and associated with a third antenna feed configured to illuminate the third rigid antenna reflector when the spacecraft is in the on-orbit configuration;
a third reflector boom with a third proximal end and a third distal end, the third proximal end coupled with the main body via a third pivot mechanism and the third distal end coupled with the third rigid antenna reflector via the third positioning mechanism;
a fourth rigid antenna reflector, the fourth rigid antenna reflector coupled with a fourth positioning mechanism and associated with a fourth antenna feed configured to illuminate the fourth rigid antenna reflector when the spacecraft is in the on-orbit configuration; and
a fourth reflector boom with a fourth proximal end and a fourth distal end, the fourth proximal end coupled with the main body via a fourth pivot mechanism and the fourth distal end coupled with the fourth rigid antenna reflector via the fourth positioning mechanism, wherein:
the third reflector boom is configured to rotate about the third pivot mechanism, the third positioning mechanism is configured to rotate the third rigid antenna reflector,
the fourth reflector boom is configured to rotate about the fourth pivot mechanism, the fourth positioning mechanism is configured to rotate the fourth rigid antenna reflector,
in the launch configuration, the third reflector boom and the fourth reflector boom are substantially proximate and substantially parallel to the main body, the aperture planes of the third rigid antenna reflector and the fourth rigid antenna reflector are substantially normal to the rotational axes of the third pivot mechanism and the fourth pivot mechanism, respectively, and a substantial portion of the third rigid antenna reflector and a substantial portion of the fourth rigid antenna reflector are forward of the forward surface and inboard of a side of the main body, and
in the on-orbit configuration, the aperture planes of the third rigid antenna reflector and the fourth rigid antenna reflector are substantially parallel to the rotational axes of the third pivot mechanism and the fourth pivot mechanism, respectively, the third reflector boom is at a substantial angle with respect to the main body, the fourth reflector boom is at a substantial angle with respect to the main body, the third rigid antenna reflector is illuminated by the third antenna feed, the fourth rigid antenna reflector is illuminated by the fourth antenna feed, and the third rigid antenna reflector and the fourth rigid antenna reflector are displaced a substantial distance from the main body in the yaw axis direction and in a direction orthogonal to the yaw axis direction.
18. The spacecraft of claim 1 , wherein the first rigid antenna reflector is characterized by a focal length, the focal length being no less than an axial length of the main body along the yaw axis.
19. The spacecraft of claim 1 , wherein the first antenna feed is approximately midway between the forward surface and the aft surface.
20. A rigid antenna reflector deployment mechanism reconfigurable between a launch configuration and an on-orbit configuration, the deployment mechanism comprising:
a first rigid antenna reflector;
a reflector boom, the reflector boom including a proximal end and a distal end;
a first positioning mechanism connecting the first rigid antenna reflector to the distal end;
and
a pivot mechanism with a first portion and a second portion, the first portion configured to pivot relative to the second portion, the first portion coupled with the proximal end, and the second portion configured to attach to a main body of a spacecraft, wherein the rigid antenna reflector deployment mechanism is configured such that:
the pivot mechanism rotates the reflector boom about the pivot mechanism rotational axis,
in the launch configuration, the aperture plane of the first rigid antenna reflector is substantially normal to the rotational axis of the pivot mechanism, and the rigid antenna reflector deployment mechanism is configured such that a substantial portion of the first rigid antenna reflector is forward of a forward surface of the spacecraft and inboard of a side of the main body, and
in the on-orbit configuration, the rigid antenna reflector deployment mechanism is configured such that the reflector boom is at a substantial angle with respect to the main body, the first rigid antenna reflector is illuminated by a first antenna feed on the spacecraft, and the first rigid antenna reflector is displaced a substantial distance from the main body in the yaw axis direction and in a direction orthogonal to the yaw axis direction.
21. The rigid antenna reflector deployment mechanism of claim 20 , wherein the first positioning mechanism is a dual-axis positioning mechanism.
22. The rigid antenna reflector deployment mechanism of claim 20 , further comprising:
a second rigid antenna reflector; and
a second positioning mechanism, the second positioning mechanism connecting the second rigid antenna reflector to the distal end, wherein the rigid antenna reflector deployment mechanism is configured such that:
the second positioning mechanism rotates the second rigid antenna reflector,
in the launch configuration, the aperture plane of the second rigid antenna reflector is substantially normal to the rotational axis of the pivot mechanism, and the rigid antenna reflector deployment mechanism is configured such that a substantial portion of the second rigid antenna reflector is forward of the forward surface and inboard of a side of the main body, and
in the on-orbit configuration, the rigid antenna reflector deployment mechanism is configured such that the second rigid antenna reflector is illuminated by a second antenna feed on the spacecraft and the second rigid antenna reflector is displaced a substantial distance from the main body in the yaw axis direction and in a direction orthogonal to the yaw axis direction.
23. The rigid antenna reflector deployment mechanism of claim 22 , wherein the first positioning mechanism and the second positioning mechanism are configured, in the launch configuration, to orient the first rigid antenna reflector and the second rigid antenna reflector, respectively, in opposite directions.
24. The rigid antenna reflector deployment mechanism of claim 22 , wherein the distal end includes a crossboom, wherein the crossboom is substantially orthogonal to the reflector boom, wherein the first positioning mechanism is coupled with a first end of the crossboom, and wherein the second positioning mechanism is coupled with the second, opposite end of the crossboom.
25. The rigid antenna reflector deployment mechanism of claim 20 , further comprising a stiffener strut, wherein a first end of the stiffener strut is coupled with the reflector boom between the distal end and the proximal end, and wherein the second end of the stiffener strut is configured to be coupled with the main body at a location other than where the pivot mechanism is configured to be connected.
26. The rigid antenna reflector deployment mechanism of claim 20 , wherein the reflector boom includes a first hinge located between the distal end and the proximal end, wherein, when the rigid antenna reflector deployment mechanism is in the launch configuration, the reflector boom is configured to be folded about the hinge such that a first portion of the reflector boom between the distal end and the hinge is drawn against a second portion of the reflector boom between the proximal end and the hinge, and wherein the reflector boom is configured, when the rigid antenna reflector deployment mechanism is in the on-orbit configuration, to be unfolded about the hinge such that the first portion of the reflector boom forms an angle substantially greater than 90° with the second portion.
27. The rigid antenna reflector deployment mechanism of claim 20 , wherein the first rigid antenna reflector is characterized by a focal length, the focal length being no less than an axial length of the main body along the yaw axis.
28. A method of reconfiguring a rigid antenna reflector deployment mechanism of a spacecraft from a launch configuration to an on-orbit configuration, the spacecraft including a main body, a forward surface, and an aft surface, the main body located substantially between the forward surface and the aft surface, and the deployment mechanism comprising:
a first rigid antenna reflector;
a reflector boom, the reflector boom including a proximal end and a distal end;
a first positioning mechanism connecting the first rigid antenna reflector to the distal end;
and
a pivot mechanism with a first portion and a second portion, the first portion configured to pivot relative to the second portion about a pivot mechanism rotational axis, the first portion coupled with the proximal end, and the second portion configured to attach to a main body of a spacecraft, wherein the rigid antenna reflector deployment mechanism is configured such that:
the reflector boom is rotatable about the pivot mechanism rotational axis,
in the launch configuration, the aperture plane of the first rigid antenna reflector is substantially normal to the pivot mechanism rotational axis, and the rigid antenna reflector deployment mechanism is configured such that a substantial portion of the first rigid antenna reflector is forward of the forward surface of the spacecraft and inboard of a side of the main body, and
in the on-orbit configuration, the rigid antenna reflector deployment mechanism is configured such that the reflector boom is at a substantial angle with respect to the main body, the first rigid antenna reflector is illuminated by a first antenna feed on the spacecraft, and the first rigid antenna reflector is displaced a substantial distance from the main body in the yaw axis direction and in a direction orthogonal to the yaw axis direction, wherein the method comprises:
rotating the first rigid antenna reflector away from the spacecraft yaw axis while the first rigid antenna reflector is positioned forward of the forward surface of the spacecraft;
rotating the reflector boom away from the main body; and
rotating the first rigid antenna reflector further away from the spacecraft yaw axis.