Intelligent capacitive sensor array for removement detection from various surfaces of tagged equipment in hospitals

Knowing the location of special equipment is a big advantage in large hospitals. Active and intelligent removement detection helps to prevents theft and manipulation. Driven by just a coin battery, ultra low power modules extend the battery life to one month and more. An intelligent detection system could adapt on many different surfaces and materials. The main item of the application is an ultra low power Microcontroller from TI, which is driven 99.44% in “sleep mode”. Therefore a high efficient DC/DC converter provides voltage for the controller to work continuously. The sensor itself is build by four single, rectangular shaped capacitive sensor areas. It is possible to differ the change of material in front of its sensitive side and supplying it with only one coin battery one month or longer. With the four sensor elements it is possible to differ between replacement and slip. The component is small and weighs little, so it can be placed directly on skin like a watch or almost invisible on technical equipment. With an additional radio transceiver the replacement of the sensor can be transmitted wirelessly.