Dynamic modeling technique for the deployment of large satellite antennas
A method for modeling a structure deployed on a spacecraft. The method includes determining a geometric shape that resembles the structure in a fully deployed configuration; generating time functions for a change in shape of at least one structural component of the structure, the change in shape occurring as the structure expands into the fully deployed configuration; and calculating mass properties of the geometric shape as a function of the time functions.
1. A method for modeling a structure deployed on a spacecraft comprising:
selecting a representative one-body geometric shape which resembles a deployed structure; and
generating time-varying mass properties of said geometric shape as a function of a physical parameter of said deployed structure that describes the degree of the deployment as one body.
2. The method of claim 1 , wherein said deployed structure comprises a flexible large reflector.
3. The method of claim 2 , wherein said flexible large reflector compnses an L-band antenna.
4. The method of claim 1 , wherein said geometric shape is taken from the group consisting of spherical, cylindrical and elliptical shapes.
5. The method of claim 1 , wherein said generating comprises calculating the rotational and translation variation of a center of mass of said deployed structure as one body.
6. The method of claim 1 , wherein said physical parameter of said deployed structure comprises at least one mechanical member having a variable length.
7. The method of claim 1 , wherein said physical parameter of said deployed structure comprises at least one mechanical member which has a variable orientation relative to other mechanical members of said deployed structure.
8. A method for modeling a structure deployed on a spacecraft comprising:
determining a one-body geometric shape that resembles the structure in a fully deployed configuration;
generating time functions for a change in shape of at least one structural component of said structure, said change in shape occurring as said structure expands into said fully deployed configuration; and
calculating mass properties of said geometric shape as a function of said time functions.
9. The method of claim 8 , wherein said structure comprises an antenna structure.
10. The method of claim 9 , wherein said antenna structure comprises an L-band antenna.
11. The method of claim 8 , wherein said one-body geometric shape comprises an elliptical cylindrical shell.
12. The method of claim 8 , wherein said one-body geometric shape is taken from the group consisting of spherical, cylindrical and elliptical shapes.
13. The method of claim 8 , wherein said calculating comprises calculating the rotational and translation variation of a center of mass of said one-body geometric shape.
14. The method of claim 8 , wherein said structural component comprises a plurality of truss members configured to support a mesh-like screen, wherein at least one of said truss members comprises a variable length and wherein at least one of said truss members changes orientation relative to said other truss members.
15. A method for modeling a structure deployed on a spacecraft comprising:
generating time functions for a structural component located on a periphery of an antenna structure as said structural component varies from a first length to a second length and as said structural component varies between a first orientation and a second orientation; and
calculating mass properties of a one-body elliptical cylindrical shell as a function of said time functions.
16. The method of claim 15 , wherein said antenna structure comprises an L-band antenna.
17. The method of claim 15 , wherein said calculating comprises calculating the rotational and translation variation of a center of mass of said elliptical cylindrical shell.
18. A method for modeling an expandable structure deployed on a spacecraft comprising:
determining a one-body geometric shape that resembles the expandable structure in a fully expanded configuration;
generating time functions for a length of a structural component of said expandable structure, said length configured to vary as said expandable structure expands; and
calculating mass properties of said one-body geometric shape as a function of said time functions for said length.
19. The method of claim 18 , wherein said expandable structure compnses an antenna structure.
20. The method of claim 19 , wherein said antenna structure comprises an L-band antenna.
21. The method of claim 18 , wherein said one-body geometric shape comprises an elliptical cylindrical shell.
22. The method of claim 18 , wherein said geometric shape is taken from the group consisting of spherical, cylindrical and elliptical shapes.
23. The method of claim 18 , wherein said calculating comprises calculating the rotational and translation variation of a center of mass of said geometric shape.
24. The method of claim 18 , wherein said structural component comprises a plurality of truss members configured to support a mesh-like screen, wherein at least one of said truss members comprises a variable length and wherein at least one of said truss members changes orientation relative to said other truss members.