Smallsat payload configuration
Techniques for deploying a plurality of smallsats from a common launch vehicle are disclosed where a structural arrangement provides a load path between an upper stage of the launch and the plurality of spacecraft. Each spacecraft is mechanically coupled with the launch vehicle upper stage only by the structural arrangement. The structural arrangement includes at least one trunk member that is approximately aligned with the longitudinal axis of the launch vehicle upper stage, a plurality of branch members, each branch member being attached to the trunk member and having at least a first end portion that is substantially outboard from the longitudinal axis; and a plurality of mechanical linkages, each linkage coupled at a first end with a first respective spacecraft and coupled at a second end with one of the plurality of branch members, the trunk member or a second respective spacecraft.
1. A system comprising:
a payload including a plurality of spacecraft configured for deployment in an orbit; and
a tree-like structural arrangement providing a load path between a launch vehicle upper stage and the plurality of spacecraft; wherein
each spacecraft is mechanically coupled with the launch vehicle upper stage only by the tree-like structural arrangement; and
the tree-like structural arrangement includes:
at least one trunk member that is approximately aligned with a longitudinal axis of the launch vehicle upper stage;
a plurality of branch members, each branch member having at least a first end portion that is substantially outboard from the longitudinal axis and a second end portion attached to the trunk member; and
a plurality of mechanical linkages, each mechanical linkage having a first respective end and a second respective end, wherein:
the first respective end of each mechanical linkage is detachably coupled with a first respective spacecraft;
the second respective end of each of the mechanical linkages is attached to one of the plurality of branch members, or the trunk member;
each of the mechanical linkages includes a spring-like coupling that provides resistance to both compression and tension, wherein:
the deployment of at least one spacecraft of the plurality of spacecraft from the system, when disposed in the orbit, comprises one of:
(A) aligning the longitudinal axis in an orientation with respect to an orbital velocity vector, the orientation being transverse to the orbital velocity vector; detaching the at least one spacecraft from respective mechanical linkages; and rotating the structural arrangement about the longitudinal axis or translating the structural arrangement by imparting an impulse directed substantially parallel to the orbital velocity vector; or
(B) aligning the longitudinal axis in an orientation with respect to an orbital velocity vector, the orientation being parallel to the orbital velocity vector; detaching the at least one spacecraft from respective mechanical linkages; and rotating the structural arrangement about an axis transverse to the longitudinal axis or translating the structural arrangement by imparting an impulse directed substantially parallel to the orbital velocity vector.
2. The system of claim 1 , wherein each spacecraft is coupled directly only with one or both of at least one of the branch members and the trunk member of the tree-like structural arrangement and not with another spacecraft such that each of the mechanical linkages is attached to one of the plurality of branch members, or the trunk member.
3. The system of claim 2 , wherein, when the at least one spacecraft is detached, each respective mechanical linkage is configured to retract toward a respective branch member, or the trunk member, to which the respective mechanical linkage is attached.
4. The system of claim 1 , wherein the orientation is transverse to the orbital velocity vector.
5. The system of claim 4 , wherein the deployment comprises rotating the structural arrangement about the longitudinal axis.
6. The system of claim 4 , wherein the deployment comprises translating the structural arrangement by imparting an impulse directed substantially parallel to the orbital velocity vector.
7. The system of claim 1 , wherein the orientation is parallel to the orbital velocity vector.
8. The system of claim 7 , wherein the deployment comprises rotating the structural arrangement about an axis transverse to the longitudinal axis.
9. The system of claim 7 , wherein the deployment comprises translating the structural arrangement by imparting an impulse directed substantially parallel to the orbital velocity vector.
10. A method comprising:
deploying, from an orbiting system including a plurality of spacecraft, a first spacecraft of the plurality of spacecraft; and
deploying, from the orbiting system, a second spacecraft of the plurality of spacecraft; wherein
a tree-like structural arrangement provides a load path between a launch vehicle upper stage and the plurality of spacecraft;
each spacecraft is mechanically coupled with the launch vehicle upper stage only by the structural arrangement; and
the tree-like structural arrangement includes at least one trunk member that is approximately aligned with a longitudinal axis of the launch vehicle upper stage, a plurality of branch members, each branch member having at least a first end portion that is substantially outboard from the longitudinal axis and a second end portion attached to the trunk member, and a plurality of mechanical linkages, each mechanical linkage having a first respective end and a second respective end, wherein:
each of the mechanical linkages includes a spring-like coupling that provides substantial resistance to both compression and tension;
the first respective end of each mechanical linkage is detachably coupled with a first respective spacecraft;
the second respective end of at least one of the mechanical linkages is attached to one of the plurality of branch members or the trunk member; and
each deploying includes detaching one of the first spacecraft or the second spacecraft from respective mechanical linkages and one of:
(A) aligning the longitudinal axis in an orientation with respect to an orbital velocity vector, the orientation being transverse to the orbital velocity vector; detaching the at least one spacecraft from respective mechanical linkages; and rotating the structural arrangement about the longitudinal axis or translating the structural arrangement by imparting an impulse directed substantially parallel to the orbital velocity vector; or
(B) aligning the longitudinal axis in an orientation with respect to an orbital velocity vector, the orientation being parallel to the orbital velocity vector; detaching the at least one spacecraft from respective mechanical linkages; and rotating the structural arrangement about an axis transverse to the longitudinal axis or translating the structural arrangement by imparting an impulse directed substantially parallel to the orbital velocity vector.
11. The method of claim 10 , wherein each spacecraft is coupled directly only with one or both of at least one of the branch members and the trunk member of the tree-like structural arrangement and not with another spacecraft.
12. The method of claim 10 , wherein, when the at least one spacecraft is detached, the respective mechanical linkages are configured to retract toward respective branch members to which they are attached.
13. The method of claim 10 , wherein the orientation is transverse to the orbital velocity vector.
14. The method of claim 13 , wherein the rotating comprises rotating the structural arrangement about the longitudinal axis.
15. The method of claim 13 , wherein the translating comprises imparting an impulse directed substantially parallel to the orbital velocity vector.
16. The method of claim 10 , wherein the orientation is parallel to the orbital velocity vector.
17. The method of claim 16 , wherein the rotating comprises rotating the structural arrangement about an axis transverse to the longitudinal axis.
18. The method of claim 16 , wherein the translating comprises, after detaching the at least one spacecraft, imparting an impulse directed substantially parallel to the orbital velocity vector.