Origami for Tunable Soft Sensors and Actuators

Origami patterns have gained interest within the soft robotic and active materials communities for their programmable and tunable mechanical properties. This presentation will discuss two recent innovations in origami-patterned soft materials, in fabrication processes and in origami-patterned sensors. The applications of origami to mechanical sensors (such as in soft robotics) will be presented first. The sensors are cast in the desired pattern and foil electrodes are applied to the pattern faces to create a capacitive strain sensor. Definition of the as-fabricated pattern angles modifies the sensor’s compliance and strain sensitivity.<br/><br/>Fabrication innovations will also be discussed. Precisely defining pattern angles in compliant or stretchable materials is a challenge. Approaches to origami soft-material patterning using both elastomer casting and direct additive manufacturing processes will be presented. In the direct additive manufactured process, PLA filament is underextruded as the structure is fabricated [1], which creates a structure that is porous, strong, mechanically robust— and flexible. The performance and tunability of origami-patterned structures fabricated in this process will be presented.<br/><br/>[1] J. Forman, M.D. Dogan, H. Forsythe, and H. Ishii, "DefeXtiles: 3D Printing Quasi-Woven Fabric via Under-Extrusion," in <i>Proceedings of the 33rd Annual ACM Symposium on User Interface Software and Technology</i> (<i>UIST '20</i>), 2020.