Generation of a Personalized Headcap 3D Model for Encephalography with Dry Electrodes

Abstract

The article presents a method for generating a 3D model of a collapsible headcap for dry electrodes of an electroencephalograph based on the parameters of a human head. A headcap for electrodes that precisely fits the head of a particular person is essential in the development of personalized human-machine brain-computer interfaces. A mathematical model is proposed, based on the approximation of the head shape using an ellipsoid and the placement of sockets for electrodes according to the international universal system 10-20. 3D bridges based on Bezier curves are used to connect sockets. The proposed method is implemented in the FreeCAD computer-aided design environment using the Python programming language. The headcap model has been generated. The accuracy of electrode placement on the headcap was verified using a 3D scan of a head obtained with a Calibry Mini scanner. The physical characteristics of the headcap are verified by printing it on a consumer-grade 3D printer. The resulting headcap is better suited for the person whose head parameters were taken than standard headcaps and requires less material and time for 3D printing.