Extended Data Fig. 3: Finite element modelling of electromagnetic and solid mechanical processes.
From: Bioelastic state recovery for haptic sensory substitution
a, Demagnetization curve of an N48 neodymium magnet. Arnold Magnetic Technologies N48 from the ANSYS material library was used for the permanent magnet part of the armature with a modification of Br to 1 T in its B–H curve. b, B–H curve of iron–cobalt (VACOFLUX 50 Solid) and PDMS–MNP. The PDMS–MNP diaphragm used a self-defined material with a relative permeability of 1.04 and a bulk conductivity of 4 S m−1. c, Example quasi-magnetostatic simulation showing the magnetic field strength and direction as a colour map and quiver plot (Icoil = 400 mA) for the compressed and relaxed states (*||B|| = 7.4 mT, stray magnetic field at 6.6 mm radial distance from central axis). d, Model geometry and boundary conditions for solid mechanical processes. A downward displacement was applied to the armature and the corresponding reaction forces from the skin phantoms were evaluated. e, Example simulations showing strain distribution within a skin phantom (45:1, E = 43 kPa) for the relaxed and compressed states (2 mm effective indentation). f, Schematic of the mass–spring–damper vibration model for the transducer and the periodic loading force applied to it. g, Stress distribution within the kirigami structure in the relaxed state (PET yield stress, 80 MPa). h, Stress distribution within the kirigami structure in the compressed state. i, In-plane strain of the skin phantom in the compressed state. A stiff skin phantom was used here to evaluate the upper bound of stress in the structure (E = 5.1 MPa). j, In-plane deformation of the skin phantom in the compressed state.
