Patent attributes
A device may include a flexible material defining an exterior of a cavity, an interior electrode located within the cavity, a first peripheral electrode peripherally located with respect to the interior electrode on a first side of the interior electrode, a second peripheral electrode peripherally located with respect to the interior electrode on a second side of the interior electrode where the interior electrode is between the first peripheral electrode and the second peripheral electrode, a controller electrically connected to the interior electrode, the first peripheral electrode, and the second peripheral electrode, and programmed instructions written into memory of the controller where the programmed instructions cause the controller, when executed to measure a first capacitance between the first peripheral electrode and the interior electrode and measure a second capacitance between the second peripheral electrode and the interior electrode.