Centripetal Force Technique

One main design concept was to use centripetal forces to deploy thearray. These forces would be a result of the inertia of the structure due to its rotation around a central axis. The centripetal forces would also be a source of stiffness for the structure. .The centripetal force deployment design concept consisted of a central hub, spokes (guy wires), and an outer rim. This concept was an adaptation of the bicycle wheel design by Dr. Seth Potter of New York University. Dr. Potter's design is shown in Figure 5.

Figure 5: Centripetal Design

Two rocket launches would be utilized in placing the materials for this design in space. One launch would deliver the hub, rim, and spoke elements into a LEO. The second launch would contain the solar array material. Once in space the solar array could be attached to the hub, rim, and spokes. The rim and spokes would be in a compacted state. The rim and spoke elements would be manufactured like a retractable car antennae with smaller elements collapsing inside the next larger element. The attachment of the solar array to the collapsed element would prove less difficult than trying to attached the solar array to a fully deployed one kilometer diameter circle. The attachmentof the solar array to the structure could be accomplished manually by astronauts or automatically using robots or remote control.

Once assembled, the collapsed structure would then be boosted to its operational geostationary Earth orbit. A force will then be applied to the design to initialize a spinning motion. This force must be initially large enough to cause an inertial force that will begin to pull the rim outward. The rim's expansion will pull the spokes and solar array along with it. The satellite will continue spinning and thus pull the entire design out to its maximum length. Once fully deployed the spinning will continue, causing tension in the spokes and adding stiffness to the array.7