Computational Design and Single-Wire Sensing of 3D Printed Objects with Integrated Capacitive Touchpoints

Producing interactive 3D printed objects currently requires laborious 3D design and post-instrumentation with off-the-shelf electronics. Multi-material 3D printing using conductive PLA presents opportunities to mitigate these challenges. We present a computational design pipeline that embeds multiple capacitive touchpoints into any 3D model that has a closed mesh without self-intersection. With our pipeline, users define touchpoints on the 3D object’s surface to indicate interactive regions. Our pipeline then automatically generates a conductive path to connect the touch regions. This path is optimized to output unique resistor-capacitor delays when each region is touched, resulting in all regions being able to be sensed through a double-wire or single-wire connection. We illustrate our approach’s utility with five computational and sensing performance evaluations (achieving 93.35% mean accuracy for single-wire) and six application examples. Our sensing technique supports existing uses (e.g., prototyping) and highlights the growing promise to produce interactive devices entirely with 3D printing.

S. Sandra Bae, Takanori Fujiwara, Danielle Szafir, Ellen Yi-Luen Do, Michael L. Rivera. 2025. "Computational Design and Single-Wire Sensing of 3D Printed Objects with Integrated Capacitive Touchpoints". In: SCF '25: Proceedings of the ACM Symposium on Computational Fabrication. (Cambridge, MA, November 19, 2025)