Multisensoric

Electronic tongue to “taste” concrete

Figure: Horst Ahlers

The Jena electronic tongue (“Multiionen-Sensoriccard”) is composed of a measuring head with ten electrodes for eight measurement channels to determine the vector components, an electronic unit, a USB cable and a computer

Figure: Horst Ahlers

The vector components provided by the individual measurement channels are shown as characteristic curves to distinguish the individual concrete mixes, or as a fingerprint

Figure: Horst Ahlers

About ten years ago, a concrete specimen 12 x 8 x 4 cm in size was produced with embedded electrodes made from metal wires consisting of various materials to evaluate the setting behavior of the concrete. To demonstrate the influence of moisture, three different types of water exposure were triggered and analyzed, as shown in the spider diagram

Figure: Horst Ahlers

One of the principles that can be applied to the design of an electronic tongue is to generate an electrochemical voltage, just like in a galvanic cell but also similar to the human or animal tongue. Both the biological and the engineered tongue generate an electrical voltage using the presence of ions. A minute amount of moisture makes substances dissociate so that they are present in ionized condition. Thanks to the research of Prof. Walther Nernst, it has been known for about 100 years that different electrodes that consist of conductive materials generate an electrical voltage from the...