Trw Limited

Northrop Grumman Systems Corporation

Dean R Dailey

Lee E Elliott

Allen J Bronowicki

Jonathan W Arenberg

A Dale Parker

Martin Richard Flannery

Larry N Gilman

Nicholas B Dailey

Charles F Lillie

An exemplary starshade comprises a tensegrity truss structure having a central hub with radially extending, telescoping booms. Telescoping tension struts connected to the central hub and booms provide a compressive force on the booms during final truss deployment. Opaque petals, not supported by the tensegrity truss structure prior to its final deployment, are each sequentially placed on and attached to the tensegrity truss structure in side by side position to form a concentric ring of petals spaced apart from the central hub. A fan fold covering, not supported by the tensegrity truss structure prior to its final deployment, is placed on and attached to the tensegrity truss structure to form an opaque, concentric inner ring about the central hub. An outer edge of the inner ring is adjacent an interior edge of the concentric ring of petals to block light from the petals to the central hub.

Starshade with attributes facilitating assembly

A positioning boom disposed between a space-based observatory platform and its instrument payload provides thermal and dynamic isolation as well as fine pointing and momentum control. The inventive system isolates a sensitive payload from a warm, dynamically noisy spacecraft, which includes a sunshield. Isolation is required in terms of dynamics and heat flow, both in terms of the absolute level and its variance (thermal isolation). The present invention provides intrinsic control over momentum buildup (which is due to the separation of the center of pressure from the center of mass). The space-based platform also provides a view (field of regard) to at least half the sky (in the anti-sun direction).

Isolating positioning boom for instrument platform

The power to weight ratio obtained with a spacecraft's solar array ( ) is enhanced by a factor of at least two to five through use of support structure for individual solar panels or solar arrays ( ) containing a curved outwardly bowed surface as deployed that packs essentially flat for storage. Defining a D-shaped wing ( ) in cross-section as deployed, the support structure ( & ) for a string of solar cells ( FIG. ) provides greater inertia and thereby greater rigidity than prior designs. One member ( ) to the support structure is relatively flexible. One-hundred and eighty degree strain energy hinges ( ) carried by the other support member ( ) outwardly bows that flexible to define a curved sector when the support structure is released from the stowed condition in which the support structure is held relatively thin and flat.

D-wing deployable solar array

The power to weight ratio obtained with a spacecraft's solar array (3) is enhanced by a factor of at least two to five through use of support structure for individual solar panels or solar arrays (31a-17a) containing a curved outwardly bowed surface as deployed that packs essentially flat for storage. Defining a D-shaped wing (15a) in cross-section as deployed, the support structure (4 & 6) for a string of solar cells (10, FIG. 3) provides greater inertia and thereby greater rigidity than prior designs. One member (4) to the support structure is relatively flexible. One-hundred and eighty degree strain energy hinges (19) carried by the other support member (6) outwardly bows that flexible to define a curved sector when the support structure is released from the stowed condition in which the support structure is held relatively thin and flat.

A precision deployable boom assembly 10 for terrestrial and celestial applications comprises an extendable and retractable boom 12 having a fixed end 14, a movable distal end 20 and three or more cables 30 attached to the distal end to form a tripod configuration of the deployed boom. The boom is spring biased to urge extension of the boom and to produce a tensile pre-load in the cables. The cables are wound and unwound by cable drums 28 selectively driven by precise motors such as stepping motors 33. The cables are preferably formed of graphite which provides high stiffness, light weight and a very low coefficient of thermal expansion. The position of the distal end is highly stable at all deployed lengths of the boom and is also precisely repeatable.

Growing community of inventors

Torrance, CA, United States of America

Dean R Dailey