A flexible sensor for soft-bodied robots based on electrical impedance tomography

Soft robotics is a well established research field that is already making an impact on the robotic community in many different ways. Despite this, the paradigm of soft materials brings also enormous challenges and unique problems. One of the most challenging topics is providing sensing capability to the soft device. In this paper we present a flexible sensors made with the same material used to build soft robots (silicon rubbers) over which a tomographic technique known as Electrical Impedance Tomography has been used as transduction method. The technique can be used to develop a flexible sensor with arbitrary size and shape that does not suffer from the presence of wires within the sensing area. This allows to have distributed and continuous sensing without the need to include multiple sensing elements. We tested the developed system by analysing its respond to the elongation and bending of the sensor. The results are promising and provide sound basis for the development of novel sensor for soft robots.

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