Unmanned Systems Technology 036

89 Additive manufacturing | Focus initial printer for this new process is 25 x 25 x 25 cm but there is no limit on the size. The first way to scale up is to use 10 or 20 robot arms for parallel operation, and then make them faster and larger. Using industry-rated sheet materials of continuous carbon strands achieves strength-to-weight ratios well in excess of metals. They can also be used to integrate other materials into the composite, particularly for wireless charging, where the legs of a UAV can be built from SLS nylon with inserts that include the bottom charging pad so that they do not heat up the legs. SLS is also used with composite plastics that are filled with carbon or glass fibre, as these melt at a lower temperature than metal and so can be produced faster. They can also be CNC-milled in the same way as metal, and can meet the tolerance and surface finish requirements of aerospace and unmanned system component designs but with lower weight than metal. Combining materials One proprietary composite-based AM technology (CBAM) combines long-fibre fabrics of carbon or glass with high- performance polymer powders such as PEEK (polyether ether ketone) to make long fibre composite parts with a resolution down to 2 microns by using ultra-fine layers that are 5 microns thick. They can be used for the micro- connectors, fibre optic systems and lenses in unmanned systems, and are scalable for mass production. These new materials join carbon fibre and fibreglass sheets paired with PEEK, PA 6, PA 12 and most other thermoplastics. CBAM can produce parts up to 10 times faster than conventional AM systems, printing sheets measuring up to 25 x 25 cm. 3D printing with silicone is also emerging for producing custom flexible shapes, in particular for seals. This uses a spray technique where the silicone is set by heat or UV light; that can slow down the production rates though. Combining techniques The experience of one UAV maker gained from using conventional technologies and AM in plastic, metal and composite materials is that a combination of techniques is necessary. Different techniques are suitable for different needs, from prototyping to production and for different parts of an aircraft. So a new AM technique called Additive Moulding aims to combine several approaches. This combines a plastic AM Unmanned Systems Technology | February/March 2021 AUSTRALIA Evok3D +61 417 128 356 www.evok3d.com.au AUSTRIA Voestalpine High Performance Metals +49 211 522 0 www.bohler.de/en BELGIUM 3D Systems +32 16 94 64 00 www.3dsystems.com Materialise +32 16 39 66 11 www.materialise.be CANADA Burloak Technologies +1 905 592 0244 www.burloaktech.com FRANCE Pollen – www.pollen.am Poly-Shape +33 164 851 310 www.poly-shape.com GERMANY 3D Systems +49 6151 3570 www.3dsystems.com CITIM +49 39 203 51 060 www.citim.de Concept Laser +49 9571 16790 www.concept-laser.de EOS +49 89 893 36 134 www.eos.info ExOne +49 82 174 760 www.exone.com GKN Additive +49 228 9335 0 www.gknpm.com Oerlikon +49 39203 5106 0 www.oerlikon.com/am OWL Additive Manufacturing +49 176 427 82129 www.owl-additive-manufacturing.com ITALY 3NTR +39 0321 91528 www.3ntr.eu CRP Technology +39 059 821 135 www.crp.eu/www.windform.it Examples of additive manufacturing suppliers