Spatial sEMG Pattern-Based Finger Motion Estimation in a Small Area Using a Microneedle-Based High-Density Interface

Abstract

The human finger exhibits fine motor skills that are widely used in daily activities. Thus, the motion estimation of a moving finger has several potential applications. Several surface electromyography interfaces have been proposed to estimate finger motion by analyzing finger-related muscles. However, due to the characteristics of the muscles, they are time-consuming to operate, require precise electrode placement, or are impractical to use. In this letter, a high-density spatial pattern-based finger motion estimation method is proposed that uses a microneedle-based high-density interface. Microneedles penetrate the highly resistive dead skin layer and make direct contact with the living epidermis, without requiring an additional medium. Therefore, the sensitivity of the proposed interface exceeds that of other conventional interfaces based on traditional electrodes. Additionally, a spatial pattern that aids in motion estimation can be obtained in a small area by using the proposed interface. Grasping motion estimation, finger joint angle estimation, and finger flexion classification are performed to demonstrate the usefulness of the proposed interface and the spatial pattern-based approach.