Contents 1. INTRODUCTION
This paper extends the work reported at last year's IEEE Aerospace conference where the design principles and fabrication of Electronic Tongue No. 1 (E-Tongue 1) were described [1]. The E-Tongue 2 substrate contains a number of sensors but only the characterization of the REDOX electrodes and conductivity sensors are described in this paper. REDOX sensors were characterized using Cyclic Voltammetry (CV) [2] and Anodic Stripping Voltammetry (ASV) [3]. The additional sensors are ISEs (Ion Selective Electrodes) and GAL (Galvanic) Arrays composed of dissimilar metals such as Ni, Fe, Cu, and Zn and are intended for metal corrosion studies. The substrate also contains a thermometer and heater. The blue dots are dielectric material covering 39 pins used to connect the sensors via underside traces to the electronics board to be discussed later. Schematic view of E-Tongue 2 3.3-cm (1.3-inch) diameter ceramic substrate with 20 sensors and one heater.
