Electromagnetic state sensing devices

Abstract

A container includes a surface and a first resonance portion. The surface defines a volume of the container, and the first resonance portion includes an assembly of three-dimensional (3D) carbon-containing structures printed on the surface of the container using one or more first carbon-based inks. The first resonance portion is configured to indicate a presence of an item within the container by resonating at one or more predetermined frequencies in response to an electromagnetic radiation ping associated with a user device located a distance from the container. In some implementations, the container may include a second resonance portion including an assembly of 3D carbon-containing structures printed on the surface of the container using one or more second carbon-based inks, the one or more second carbon-based inks being different than the one or more first carbon-based inks.

Dependencies are inferred from the claim text.