Non-contact, capacitive, portable presence sensing

Abstract

A movement-sensitive capacitive sensor includes a first conductive element and a second conductive element positioned adjacent to the first conductive element. The sensor also includes a first protective insulator and a second protective insulator sealed to the first protective insulator with the first conductive element and the second conductive element positioned between the first protective insulator and the second protective insulator. The sensor further includes a circuit configured to calculate, over time while a person is occupying the movement-sensitive capacitive sensor and moving while occupying the movement-sensitive capacitive sensor, capacitance values between the first conductive element and the second conductive element. The circuit also is configured to determine an occupancy state of the movement-sensitive capacitive sensor based on the calculated capacitance values, determine movement-sensitive measurements based on the calculated capacitance values, and transmit output based on the determined occupancy state and the determined movement-sensitive measurements.