The objective of this study is to extend the application of the spray-coated tactile sensor, ScoTacS, which is being developed by the authors and can be constructed simply by “coating” with a spray gun, from one dimension to two dimensions, and further to configure it into various shapes such as a ring. This sensor is constructed by coating three layers-conductive, piezoelectric, and resistive films-in sequence. It is based on a unique principle by which the contact position is detected from the delay time, i.e., the time difference between the arrivals of peaks in the output signals. As the delay time varies with the contact position, it can be used to estimate the contact position. In this paper, after analyzing the characteristics of one-dimensional sensors, such as linear and ring sensors, we present the equivalent circuit models and experimental results of a two-dimensional sensor fully coated on a cylinder.

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