Integration of structurally embedded vascular antenna (Seva) in a complex curved composites

Recently, a reconfigurable structurally embedded vascular antenna (SEVA) has been demonstrated in flat epoxy/quartz fiber composite panels based on the transport of liquid metal within embedded microchannels. The liquid metal is a non-toxic eutectic gallium-indium alloy which remains liquid down to -19°C, has low viscosity, and has high electrical conductivity. Patterned microchannels are created using fused deposition printing of sacrificial catalyzed poly(lactic acid) cPLA followed by transfer, composite lamination, composite cure, and then thermal removal of the sacrificial cPLA during post-cure. It has been previously demonstrated that when the resulting embedded channel are progressively filled with liquid metal and electromagnetically connected, their resonant frequency can be tuned over a large frequency range depending on the resulting shape of the liquid metal trace. The large frequency response, small footprint, low volume of the metal (<2%), and retention of an aerodynamically efficient shape makes SEVA attractive for reconfigurable aircraft antenna. Mechanical modeling and experimental testing of the microvascular panels has shown modest decreases in tensile strength due to the microchannels. This paper will describe the composite fabrication of a multi-element SEVA antenna array within a complex curved article that resembles an aircraft leading-edge.