In the last three decades, after the first discovery of conductive polymers made by Shirakawa et al.[1], a great deal of interest has been devoted to the use of those materials because of their flexibility, the low cost processability, the light weight, the easiness of tailoring their properties in order to obtain the needed characteristics.udThere are different types of conductive polymers, such as polyacetylene, polypyrrole, polythiophene, polyphenylene, polyaniline, etc. Polythiophenes, in particular, represent an important class of conducting polymers due to their solubility, processability, and environmental stability, beside possessing excellent electrical conductivity, electroluminescent property, and non-linear optical activity.udThis activity is based on the Poly(3,4-ethylenedioxythiophene)/Poly (Sodium 4-Styrene Sulphonate) (PEDOT:PSS) that shows high conductivity, transparency and possesses great environmental stability [2]. PEDOT:PSS have been used successfully in different types of applications, including various types of sensors.udThis work is focused on the realization of piezoresistive sensor based on PEDOT:PSS. These devices change their electrical resistance when they are bent. The substrate is totally flexible, low cost, customizable, based on Poly (Trimellitic-udanhydride-chloride copolymerized with 4,4-methylenedianiline) in N-methylpyrrolidone.udAn ad-hoc measurement was realized in order to obtain an electrical resistance sensor measure. The idea is to replicate as really as possible the human finger flexion/extension movements. The set-up consists of three hinges controlled by three step-by-step motor to measure an array up to three different sensors. All the system is remotely controlled by Labview NI Interface and the resistive response of the sensor is read by a 5.5 digits 34405A Agilent digital multimeter.udAmong several possibilities to adopt these sensor, my first aim is a glove-based system realization. An instrumented-glove (called Hiteg Glove) is the ensemble of mechanical to electrical transducers, a support (usually Lycra based), conditioning electronics plus power supply, transmission system, all useful to measure the 23 degree of freedom [3] of finger joint movements. Thanks to their lightness, cheapness and the fact that I experienced a novel way of their application which, the bend sensors was utilized ad transducers. Each sensor was mounted on the glove in correspondence of one human hand joint so to permit the flexion/extension movements registering. Moreover ad-hoc projected sensors were utilized for the abduction/adduction movements.udThe last step of this works provides to realize a 3D Virtual Model of the glove. The basic model of the virtual hand was realized starting from Blender, which is an open source multiplatform software for 3D graphical applications. It has a robust feature set and has the interesting capabilities of texturing, skinning, animating, rendering. Virtual Hand permits a real-time replay of the hand movements obtained with the glove.udThe instrumental glove including virtual reality represents a lot of opportunity for several significant fields: social, as sign language recognition and as alternative support to actual general purpose pc input devices; medical, for functional analysis, for rehabilitation follow up on patients with damaged upper/lower limbs and for medical staff training; working, for staff training in dangerous conditions or gesture recognition; sport, in order to recording movement and posture monitoring during activity or effect of external parameters evaluation on physical performances; entertainment, as games, multimedia or music.
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