Electrical Impedance Tomography for Artificial Sensitive Robotic Skin: A Review

Abstract

Electrical impedance tomography (EIT) is a nondestructive imaging technique used to estimate the internal conductivity distribution of a conductive domain by taking potential measurements only at the domain boundaries. If a thin electrically conductive material-that responds to pressure with local changes in conductivity-is used as a conductive domain, then EIT can be used to create a large-scale pressure-sensitive artificial skin for robotics applications. This paper presents a review of EIT and its application as a robotics sensitive skin, including EIT excitation and image reconstruction techniques, materials and skin fabrication techniques. Touch interpretation via EIT-based artificial skins is also reviewed.

Development of a High-Speed Current Injection and Voltage Measurement System for Electrical Impedance Tomography-Based Stretchable Sensors

“…A number of studies have been conducted regarding the best choice of the threshold factor [7,21], but still heuristic selection is very common. In our case, we choose f = 0.10, as it performed best in our experiments.…”

“…Recently, EIT has been also employed for showing the internal impedance distribution of conductive fabrics that respond to touch with local changes in conductivity, and was therefore used for developing an artificial skin as a large-area pressure sensor [7]. Such sensors have the advantage of being stretchable, and can be placed over surfaces with a different topology.…”

An Instrumental Electrode Configuration for 3-D Ultrasound Modulated Electrical Impedance Tomography

“…Consequently, sensing and imaging these properties noninvasively could play a role for diagnosing disease, for example cancer detection. Conventional electrical impedance tomography (EIT) reconstructs the conductivity distribution by injecting current into the imaging object and measuring the resulting voltage on its boundary [1–3]. EIT has merits for being safe, non-invasive, low-cost and portable.…”

Towards the Development of an EIT-based Stretchable Sensor for Multi-Touch Industrial Human-Computer Interaction Systems

“…The EIT method is mostly applied in clinical applications [1], but it can be used to create artificial sensitive skins by using thin, conductive and flexible fabric materials that respond to a mechanical solicitation by changing their internal resistance. The main advantage of such EIT systems is the possibility to achieve a stretchable sensor without internal wires, which can be easily mounted over 3D and deformable surfaces showing multi-touch sensing capabilities [2]. In literature, some other EIT applications are for damage detection [3] and pressure sore prevention [4].…”