Automatically detecting fluid intake using conductivity measurements of beverages in a cup

This contribution presents an automated approach to generate drinking protocols. This documentation process is used in nursing homes in order to prevent dehydration in elderly people. Smart cups are used to deduce fluid intake from filling levels. Electrodes at different vertical positions allow to detect discrete filling levels depending on the amount of beverage in the cup. A conductive sensor is combined with an inductive charging unit and a radio module in order to build a functional prototype with regard to food compliance, dishwasher compatibility and subtle appearance. An evaluation of the sensor has shown a strong influence of the beverage type. While water and most soft drinks result in unambiguous measurements, remnants, especially of milk, disturb an interpretation of sensor values severely. However, the prototype offers a reliable way to automatically monitor fluid intake of those unproblematic beverages.