Self-sensing Elastomeric Membrane for Haptic Bubble Arrray.

Bubble arrays are new type of devices that can render forces to the user’s skin by pressurizing thin membranes. These devices are suitable for wearables due to being soft while having low encumbrance to the user body. In this manuscript, we describe a solution to tackle the major challenge towards controllability of this devices: state estimation of the membrane. This work describes the manufacturing of a self-sensing composite elastomeric membrane, device integration and the methods for state estimation using deep learning architectures. Additive manufacturing was used to fabricate the membrane and a pneumatic bubble actuator was operated at low pressures (10 psi). This membrane is thin $(700 \mu \mathrm{m})$, soft (3 MPa), and includes a matrix of elastomeric capacitors for distributed sensing of deformation. Our model predicted the magnitude of deformation with a mean absolute error MAE =0.321 mm corresponding to 13.1% accuracy.