JUL 2018


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NEWS 39 UAV Update around and between the spar caps, and the bottom skin was vacuum bagged in place against the construction. e top skin was then fitted to the bottom and wrapped in 12K tow. All fabrics were infused with West Systems 105, a low-viscosity epoxy supplied by Gougeon Bros. Inc. (Bay City, MI, US). All molds were CNC- machined from RenShape 440 polyurethane foam, provided by Freeman Manufacturing & Supply Co. (Avon, OH, US). To make the fuselage, which houses its gasoline engine (see the Side Story on p. 38) and fuel tank, the team used a simple cylindrical concrete mold, applied two plies of unidirectional fabric, one at 90° and one at 45°, to the inner diameter of the tube, then used a toroidal vacuum bag positioned through and around the tube, to vacuum infuse the fabric, with the outside layer of the laminate positioned against the inner wall of the tube. To fabricate the nosecone, which contains the communications electronics, an external conic-shaped mold was machined in two halves from foam. A single layer of 0° Kevlar fabric was laid up on the mold halves (which had been bonded together) and vacuum infused. FIG. 4 Production drone in action Researchers at the University of Stuttgart put theory into action, fabricating this long-span demonstrator "cantilever" structure by the novel fiber-winding process described in in Fig 3 (p. 38). The 12m long part, representative of long-span parts, such as roof sections or pedestrian bridges that could be built using the process, was wound from a combination of continuous glass roving and continuous carbon fiber tow, both pre-impregnated (epoxy) and dry fibers dipped in an epoxy resin bath. Source | University of Stuttgart High Density Urethane Tooling Board and Core Material (800) 845-0745 • • Custom Bonded Blocks • Large sheet sizes up to 5' x 10' • Any thickness to 24" • Turnaround time of DAYS, not WEEKS • No out-gassing • 15 standard densities to 75pcf Manufacturers of Precision Board Available in high-temp (<300º F) and low-temp (<200º F) YOUR PARTNER IN... COMPOSITE CURING OVENS B a t c h O v e n s • C o n v e y o r O v e n s • D r u m H e a t e r s Questions? We'd be happy to help and welcome the opportunity to do business together! So give our Engineers a call at 419.502.2780 or email us at Visit us online:

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