A System for Electrotactile Feedback Using Electronic Skin and Flexible Matrix Electrodes: Experimental Evaluation.

Area of Science:

• Biomedical Engineering
• Neuroscience
• Rehabilitation Technology

Background:

• Myoelectric prostheses restore motor function via muscle electrical activity but lack somatosensory feedback.
• Existing sensory substitution methods use simple sensors and discrete stimulation, limiting feedback sophistication.

Purpose of the Study:

• To develop and evaluate a novel system for sophisticated electrotactile feedback in prosthetic devices.
• To integrate advanced distributed sensing (electronic skin) with matrix electrode stimulation for enhanced sensory substitution.

Main Methods:

• A novel electrotactile feedback system combining electronic skin with matrix electrodes was designed.
• Eight healthy subjects performed recognition tasks involving dynamic movement patterns (lines, geometries, letters) presented on the electronic skin.
• Performance was evaluated based on the subjects' ability to recognize shape, trajectory, and direction of stimuli.

Main Results:

• The system successfully translated mechanical interactions into recognizable moving electrotactile profiles.
• High shape recognition rates were achieved: 86±8% for lines, 73±13% for geometries, and 72±12% for letters.
• Subjects demonstrated high confidence in identifying the direction of movement stimuli.

Conclusions:

• The developed system provides sophisticated tactile feedback, crucial for advancing closed-loop myoelectric prostheses.
• This technology facilitates improved control and embodiment of artificial limbs by providing comprehensive sensory information.
• Results support the potential for advanced sensory substitution to bridge the gap in prosthetic feedback.