Design and evaluation of a voltage-controlled current source for galvanic vestibular stimulation research

Galvanic Vestibular Stimulation (GVS) is a non-invasive technique that stimulates the vestibular system, which is crucial for maintaining balance and processing spatial orientation. The integration between the visual and vestibular systems, known as Oculo-Vestibular Recoupling (OVR), has shown promising potential in reducing motion sickness and enhancing immersion in Extended Reality (XR). However, a noticeable challenge in GVS research is the lack of open-sourced devices, with most studies relying on self-made prototypes or constant current power supplies. The prototyping of such devices necessitates rigorous testing and calibration, processes that are both resource-intensive and time-consuming. These challenges are particularly pronounced for researchers with limited expertise in electronics, thereby increasing the safety risks and complicating the reproducibility of experimental results. To address these issues, this paper introduces an open-source voltage-controlled current source (VCCS) module specifically designed for GVS. The proposed module provides a safe, stable, and compact solution. This study details the hardware development, performance evaluation, and wireless integration of the module, as well as a simple control methodology. Furthermore, a small-scale user study is conducted to validate the feasibility and user perception of GVS using the proposed module. This comprehensive approach aims to offer an easily accessible solution for researchers engaged in GVS-related studies.