Projeto de eletromiógrafo miniaturizado com conexão wireless e integração com braço robótico

Abstract

Supported by the objective of designing an accessible, relevant, useful and easily reproducible product, this work contemplates the construction of a miniaturized electromyograph for Surface Electromyography or Surface Electromyogram (sEMG), with wireless connectivity, and its integration with a robotic arm made in 3D printing, in order to similarly illustrate the operation with an active prosthesis. In addition to the purpose already mentioned, many areas have the sEMG as an important tool: several clinical analyzes use measurements of biopotentials correlated, such as Electrocardiogram (ECG), Electroencephalogram (EEG), Electrogastrography (EGG), Electrooculogram (EOG), Electrocochleography (EcochG), etc.; and also tend to benefit from the scenario that fostered this work; in addition, of course, to physical therapy analyses, biomechanical and kinesiological studies that frequently use sEMGs for clinical or academic purposes. Even in the booming industries of video-games, wearable devices and remote medicine, there is a myriad of applications for sEMGs. The bias of accessibility proposed in this project also supported the choice of devices used, with the search for low-cost care, high diffusion rates, availability and materials for theoretical support, culminating in the choice of a conjunction between the electromyographic sensor Myoware with the ESP32 microcontroller, resulting in a final product with an excellent relation cost-effective, reduced dimensions, wireless connectivity and interesting computational potential — especially when considering the possibility of association with other devices such as computers or smartphones. With equal success, the InMoov robot arm manufactured in 3D printing to symbolize the production of an active prosthesis at a considerably lower cost and independently — has proven to be an excellent choice to illustrate the operation of the electromyograph in a more perceptible and material way. The capabilities of ESP32 proved to be oversized, and there may be a choice for another microcontroller that meets the requirements pertinent to an sEMG (such as minimum sample rate and wireless connectivity) while being smaller in size and requiring less power; as for the sensor (which is the main component), some features can be indisputably highlighted as positive, such as easiness to use, already enveloped or raw signal disposition, good resolution and physical dimensions, but it also lacks dynamism in its Inter-Electrode Distance (IED) (fixed in 30 mm), restricting the sEMGs only to muscles that require less specificity in the readings. To validate the performance of the designed equipment the diversification of scenarios was sought for the practice of sEMGs, as well as regions of analysis, individuals and types of stimuli. The results were shown to be in accordance with the theoretical references and other sEMGs practiced in similar parameters, validating thefunctioning of the electromyograph as well as the favorable impact on the advent of wireless communication, significantly increasing the patient’s freedom of movement while mitigate artifacts of various natures.