Presentation description

Noninvasive sensory feedback has the potential to significantly improve rehabilitation technologies such as prosthetic limbs, while also enhancing immersive experiences in virtual and augmented reality. However, a key challenge remains that wrist motion affects the intensity and location of referred sensations on the distal limb, complicating the delivery of consistent feedback. Up to half of upper-limb prostheses are abandoned, often due to unreliable or inconsistent sensory feedback, highlighting the need for more stable, intuitive solutions. This study investigates how wrist motions, specifically flexion and extension, affect the perceived intensity of transcutaneous electrical stimulation.
Electrical stimulation was applied to the wrist of healthy participants as they moved through different joint angles. A camera-based tracking system recorded wrist flexion/extension, while participants used an interactive interface to adjust stimulation parameters in real time at different wrist positions. Initial findings suggest that the wrist angle significantly alters sensation intensity and localization. Extension typically produced stronger, more distal sensations than flexion.
To counteract this, participants tuned the stimulation amplitude to maintain a consistent intensity across wrist angles. Data collection is ongoing, but preliminary trends show that there are common trends in how people perceive the change. Many participants need less stimulation during extension and more stimulation during flexion. Some people are also outliers and perceive the change in stimulation differently, resulting in graphs that don't follow common trends. One participant even had the inverse effect, needing more stimulation at extension and less at flexion to keep the sensation consistent.
These results could be used to help develop algorithms that provide consistent intensity corresponding to wrist motion. Paving the way for more intuitive, stable sensory feedback in prosthetic limbs and augmented reality systems.