The myokinetic control interface: tracking implanted magnets as a means for prosthetic control

Area of Science:

• Biomedical Engineering
• Neuroscience
• Robotics

Background:

• Upper limb amputation significantly impacts object manipulation abilities.
• Current human-machine interfaces (HMIs) for prosthetic control often rely on electrophysiological signals, with limitations in achieving naturalistic control.
• There is a need for advanced HMIs that offer intuitive and comprehensive control over dexterous prosthetic devices.

Purpose of the Study:

• To introduce and demonstrate a novel myokinetic control interface for prosthetic limb restoration.
• To enable direct and simultaneous control over multiple digits of an artificial hand through a new HMI.
• To validate the precision, linearity, and responsiveness of the proposed myokinetic control system.

Main Methods:

• Developed a myokinetic control interface utilizing implanted permanent magnets and magnetic field sensors to track muscle contractions.
• Integrated six 3-axis magnetic sensors to precisely localize four implanted magnets within a forearm mockup.
• Utilized the sensor data to generate motor commands for controlling a dexterous hand prosthesis.

Main Results:

• The myokinetic control system demonstrated high linearity (R² = 0.99) and precision (1% repeatability).
• The system exhibited a short computation delay of 45 ms.
• Cross-talk errors were minimal, recorded at 10% of the mean magnet stroke.
• The prototype successfully controlled a dexterous hand prosthesis, enabling multi-digit actuation.

Conclusions:

• The myokinetic control interface presents a viable and promising approach for restoring upper limb function in amputees.
• This HMI facilitates direct and simultaneous control over multiple digits of an artificial hand, enhancing prosthetic dexterity.
• The demonstrated precision and low latency suggest significant potential for improving the quality of life for individuals with upper limb loss.