Figure eight linear dispenser

Abstract

A figure eight linear dispenser (10) having an optical fiber winding configuration adapted to dispense an optical fiber waveguide (14) at high speed. The dispenser (10) is built up of a series of flat winding layers, with each layer comprising an interlaced figure eight pattern. More particularly, the dispenser (10) comprises a housing having a pair of bobbins (12a, 12b) respectively centered on a pair of half-circular outer guides (13a, 13b). The optical fiber waveguide (14) is wound around the bobbins (12a, 12b) inside the outer guides (13a, 13b) in a series of layers (15a-15e) of figure eight loops (16a-16e). An optional cover may be disposed over the bobbins (12a, 12b) and the guides (13a, 13b) in order to enclose the waveguide (14). The waveguide pay-out of the dispenser (10) through a properly spaced eyelet (17) is nearly helix-free and linear as a result of cancellation of the angular momentum in the paired figure eight loops (16a-16e). The dispenser (10) permits linear (helix-free) payout at higher speeds than other types of linear dispensers. This is accomplished by a reduction in the waveguide tension for a given payout velocity. The dispenser (10) increases the applicability of fiber tethered links to a wider range of high performance missiles and vehicles because of its increased payout speed and linear payout capability. Linear payout allows ducting of the paid out fiber to avoid a direct thrust missile plume. The dispenser also uses a relative small exit aperture or eyelet (17) for the fiber waveguide (14) which reduces aerodynamic drag and radar cross section of the carrying vehicle.