Conformal 3D printing of non-planar antennas on wrinkled and folded kapton films using point cloud data

We report a reverse engineering-driven method for conformal microextrusion three-dimensional (3D) printing of functional materials on complex 3D structures and thin films of near-arbitrary topography. A non-planar tool path programming algorithm for conformal microextrusion 3D printing based on point cloud data representations of object geometry is presented. We show that the optimal nozzle-substrate standoff distance for quality 3D printing depends on the substrate's local geometric features (i.e. slope and curvature) and the tool trajectory. The impact and utility of the novel conformal microextrusion 3D printing process were demonstrated by fabrication of 3D spiral and Hilbert-curve loop antennas on various non-planar substrates, including wrinkled and folded Kapton films and origami. 3D-printed conformal antennas exhibited resonant frequencies ranging from 1.5 to 2.7 GHz with S₁₁ less than 10 db. This work provides a new method for conformal 3D printing on one-of-a-kind objects and non-planar films.