Study of low-cost, flexible graphite-based sensor for human finger movement

Abstract

Paper-based sensor devices have grown prominently in recent decades owing to their flexibility, light weight, biodegradability, and low cost. Pencil traces on the paper are the protuberant component to sense the physical parameter variation, and the geometry on the paper substrate plays a vital role in sensing applications. This study used the commercially available pencil as an electrode on a paper substrate that senses the mechanical strain on human finger movements. Two different geometries of the paper substrate were considered, and the optimized geometry was identified. Two different grades (HB and 8B) pencils were used as the drawing instrument to draw the graphite on the paper. The repeated experimental results show a better version of the proposed sensor for measuring human finger movements. The grade HB pencil provides excellent results compared to the other grade pencils.