RFID Tag System for Precise Asset Tracking & Localization

Commonly used RFID protocols are widely accepted because they are inexpensive and easy to implement. However, the associated low transmit power and narrow bandwidth typically result in coarse local-ization estimates. Often it is desirable to know the precise location of assets without reverting to an entirely different and more expensive protocol. Additionally, many industrial and other applications may desire technology that confirms the mating of components. This new program-mable sensor tag technology facilitates both precise localization and mating confirmation in-part by allowing the RFID sensor tag to become a type of distributed low-cost reader. To determine a tag attachment, this innovation utilizes a fixed location RFID sensor tag that incorporates a receptacle node to measure an electrical “influence” through resistance, capacitance, inductance, etc. Assets for which localization is desired are outfitted with “influence tags” – devices that produce a set of distinguishable responses when placed in the receptacle region of the RFID sensor tag. Mating or connections are confirmed when electrodes from an influence tag become attached to matching electrodes on a sensor tag’s receptacle node. Information obtained by the RFID sensor tag is stored in its local memory bank through which a dedicated reader can retrieve influence tag information. Potential applications exist for this technology where specific assets need to be precisely located and/or confirmation is needed when two parts have been correctly connected or attached. This RFID tag technology allows the retrieval of inventory status information in an energy efficient manner from inexpensive, small form factor hardware. Robotic retrieval of assets can be more easily facilitated with this innovation. Innovators at NASA Johnson Space Center have developed a low-cost means to refine localization and determine when specific assets have been attached or placed in set proximity of each other using radio frequency identification (RFID) technology. This innovation is comprised of both a novel RFID sensor tag that incorporates onboard microcontrollers and sensors to detect an influence, and a programmable influence tag that is attached to an asset for which RFID localization or attachment status is desired. Commercial RFID tags typically only communicate with a reader and utilize narrow spectrum frequency bands that can complicate the triangulation necessary for readers to determine an asset’s location. Additionally, an extreme radio frequency scattering environment further aggravates triangulation techniques commonly used in RFID. With this new RFID tag technology, an influence tag can provide data to a sensor tag which then feeds joint information to a reader. A proliferation of these tags in arrangement allows for precise localization of assets, is extensible to large distribution cells or monitored areas, and can provide confirmation of mated or associated parts. The RFID-Enabled Connections and Sensed Localization technology is at technology readiness level (TRL) 4 (component and/or breadboard validation in a laboratory environment) and is available for patent licensing. Please note that NASA does not manufacture products itself for commercial sale.