Ori-Sense: origami capacitive sensing for soft robotic applications

TL;DR

Ori-Sense is a novel origami-inspired capacitive sensor that provides soft robotic systems with proprioceptive feedback by translating torsional deformation into measurable capacitance changes, fabricated via dissolvable-core molding.

Contribution

This work introduces Ori-Sense, a compliant origami-inspired capacitive sensor with integrated fabrication, mechanical characterization, and validation for soft robotic applications.

Findings

Capacitance varies up to 30% with twist angle.

Low stiffness and minimal impedance suitable for soft robotics.

Finite-element simulations match experimental torque-rotation data.

Abstract

This work introduces Ori-Sense, a compliant capacitive sensor inspired by the inverted Kresling origami pattern. The device translates torsional deformation into measurable capacitance changes, enabling proprioceptive feedback for soft robotic systems. Using dissolvable-core molding, we fabricated a monolithic silicone structure with embedded conductive TPU electrodes, forming an integrated soft capacitor. Mechanical characterization revealed low stiffness and minimal impedance, with torque values below 0.01 N mm for axial displacements between -15 mm and 15 mm, and up to 0.03 N mm at 30 degrees twist under compression. Finite-element simulations confirmed localized stresses along fold lines and validated the measured torque-rotation response. Electrical tests showed consistent capacitance modulation up to 30%, directly correlated with the twist angle, and maximal sensitivity of S_theta ~ 0.0067 pF/deg at 5 mm of axial deformation.