Development of a Low-Cost, Open-Source Transcranial Direct-Current Stimulation Device (tDCS) for Clinical Trials

Transcranial Direct Current Stimulation (tDCS) has been the target of research in the search to understand its therapeutic effects on human health and the mechanisms by which these effects are mediated. The lack of standardization and the high cost of tDCS devices for clinical trials are some of the bottlenecks in the progress of tDCS research. The development of low-cost open-source devices, adaptable to research questions and that encourage innovation in the area are important. These devices can contribute to the understanding of tDCS mechanisms and effectiveness. Thus, this project presents a development of a tDCS prototype for clinical trials, consisting of hardware for electric stimulation, and a mobile app as a human–machine interface. The hardware is based on a direct current source and a microcontroller (ESP32), which communicates via Bluetooth® with the app. The mobile app was developed collaboratively with researchers. The built prototype had its performance evaluated through bench testing, showing a current production accuracy of 96.53%. It is expected that this project will facilitate access to tDCS devices to research groups that want to explore their effectiveness in most health conditions, following the methodological rigor of clinical trials.