Description
The objective of the activity is to develop, manufacture and test a latch to enhance the deployed stiffness of an existing array, by means of a slight repositioning of panels. Targeted Improvements: Increase the frequencies of the deployed array by 30%.Description: Most telecommunication solar arrays comprise in-line panels, arranged in a row. Some include lateral panels, forming a cross configuration. In the case of the latter, the frequency of the first deployed mode is increased, since the offset of the array centre of mass from the spacecraft sidewall is reduced, while maintaining array surface area and consequently power. At system level, deployed appendages need to be of sufficient stiffness to avoid dynamic coupling with the Attitude Orbit Control System. The stiffness of conventional deployed solar arrays is determined by the bending of the panel substrates and hinges. A vastly more effective concept would be one in which the panels act as membranes. This can be achieved by forming a shallow concave (or convex) faceted surface, byintroducing shallow angles between in-line and lateral panels. Extra triangular panels would be needed, to convert cross configurations into oval array shapes. The array would then resemble a spoon, albeit of very shallow depth. For such a concept to work, there would have to be effective load transfer between all panels. While existing hinges could be adapted to provide suitably stiff links between in-line/in-line and in-line/lateral panel junctions, a novel latching mechanism would have to be developed for lateral/lateral panel junctions. Any degradation in power performance, resulting from inter-panel view factors and/or non-optimal incidence angles, would have to be analysed and monitored accordingly. The required triangular panels would not pose a problem, since these can be manufactured in the same manner as flat panels, then cut diagonally. This activity will require a preliminary design, a test plan, the manufacture of a solar array latch breadboard and validation by test. Footnote: On Delegation Request activities will only be initiated on the explicit request of at least one National Delegation.