An instrumented fastener (e.g., a “tack” fastener) includes one or more light sources (e.g., light-emitting diodes) configured to produce a light beacon that includes encoded information regarding the instrumented fastener (e.g., part number), wherein the direction of the light beacon can be used...http://www.google.es/patents/US7937817?utm_source=gb-gplus-sharePatente US7937817 - Methods and apparatus for an instrumented fastener
Methods and apparatus for an instrumented fastener
