Novel postural control algorithm for control of multifunctional myoelectric prosthetic hands.

Area of Science:

• Biomedical Engineering
• Rehabilitation Technology
• Human-Computer Interaction

Background:

• Myoelectric controllers (MECs) are crucial for prosthetic hand function but face limitations in intuitive control and clinical effectiveness.
• Current MECs often require unnatural user commands, hindering seamless integration and performance.
• Postural control schemes offer a promising alternative by translating surface electromyography (sEMG) signals into hand movements.

Purpose of the Study:

• To introduce and evaluate a novel algorithm for a postural controller designed for multifunctional prosthetic hands.
• To assess the efficacy of the new controller in enabling intuitive and effective prosthetic hand operation.
• To determine the impact of different cursor-control techniques and electrode configurations on system performance.

Main Methods:

• Developed and implemented a novel postural control algorithm for myoelectric control.
• Conducted two experiments with 11 subjects to test the system's performance.
• Compared velocity versus position cursor-control techniques and evaluated the use of 3, 4, and 12 surface electrodes.
• Assessed the ability of subjects to command a six degree-of-freedom virtual hand into seven functional postures without prior training.

Main Results:

• The velocity cursor-control technique significantly improved performance compared to the position cursor-control technique.
• The number of surface electrodes (3, 4, or 12) did not affect controller performance.
• Subjects achieved high completion rates (82% ± 4%), efficient movement times (3.5s ± 0.2s), and good path efficiencies (45% ± 3%) in commanding a virtual hand.
• High-level performance was retained across multiple days after a single hour of training.

Conclusions:

• The novel postural controller algorithm is a robust and advantageous design for myoelectric control of multifunctional prosthetic hands.
• The system demonstrates potential for intuitive and effective prosthetic hand operation, overcoming limitations of current MECs.
• The controller's efficacy and user retention suggest a significant advancement in prosthetic technology.