Inkjet-printed fully-customizable and low-cost electrodes matrix for gesture recognition

The use of surface electromyography (sEMG) is rapidly spreading, from robotic prostheses and, muscle computer interfaces, to rehabilitation devices controlled by residual muscular activities. In this context, sEMG-based gesture recognition plays an enabling role to control prosthetics and devices in real-life settings. The aim of our work was to develop a low-cost, print-and-play platform to acquire and analyse sEMG signals that can be arranged in a fully customized way, depending on the application and the users’ needs. We produced 8-channel sEMG matrices to measure muscular activity of the forearm using innovative nanoparticle-based inks to print the sensors embedded into each matrix using a commercial inkjet printer. Then, we acquired the multi-channel sEMG data from 12 participants, while they were repeatedly performing 12 standard finger movements (6 extension and 6 flexion). Our results showed that inkjet printing-based sEMG signals ensured significant similarity values across repetitions in every participant, a large enough difference between movements (dissimilarity index above 0.2), and an overall classification accuracy of 93%-95% for flexion and extension, respectively.