Powered prosthetic hands are frequently abandoned due to limited dexterity and unintuitive control. Most commercial devices rely on surface electromyography (sEMG) and support only grasping gestures, falling short of the fine, continuous finger motions required for everyday tasks such as typing on a keyboard or playing a musical instrument.
In this talk, we present a series of studies addressing this gap from three complementary angles. First, we introduce an end-to-end system that infers fine finger motions in real time by modeling the hand as a robotic manipulator and encoding muscle dynamics from ultrasound video. Second, we present a low-cost, 3D-printed prosthetic hand engineered for enhanced dexterity, featuring adjustable finger spacing, a two-degree-of-freedom wrist, and independent finger pressing. Third, we propose SonoRank, a step towards calibration-free finger flexion detection from forearm ultrasound.
SonoRank learns to rank ultrasound sequence pairs by relative motion magnitude, then fine-tunes using a rest reference to classify active flexion across all five fingers without user training data. Together, these papers advance prosthetic control toward practical, calibration-free deployment with fine-finger activation, bringing us closer to restoring native hand function for individuals with upper-limb amputation.
