Wrist autonomy based on upper-limb synergy: a pilot study.

Area of Science:

• Biomedical Engineering
• Robotics
• Human-Machine Interaction

Background:

• Electrically powered prosthetic wrists enhance dexterity but increase operational complexity due to additional degrees of freedom (DOFs).
• Human multi-joint synergy offers a potential solution for managing complex prosthetic control.
• Understanding and replicating natural movement synergies is crucial for intuitive prosthetic control.

Purpose of the Study:

• To develop and validate a synergy-based wrist autonomy control strategy for prosthetic hands.
• To investigate the effectiveness of predicting wrist rotation from shoulder and elbow joint angles.
• To evaluate the impact of this method on activities of daily life (ADLs) for both healthy and amputee subjects.

Main Methods:

• Collected and analyzed 10 upper-limb joint angles during four typical ADLs to identify synergistic movement patterns.
• Established a linear regression model to predict wrist rotation angle based on shoulder and elbow joint movements.
• Conducted experimental tests with healthy and amputee subjects using the developed control strategy and evaluated task completion time and compensatory movements.

Main Results:

• The synergy-based wrist autonomy method effectively improved the completion efficiency of multiple ADLs.
• The proposed method did not increase the overall control complexity for prosthetic hand operation.
• Significantly reduced compensatory movements in multiple joints compared to traditional prostheses with an inactive wrist.

Conclusions:

• Synergy-based wrist autonomy is a viable strategy for enhancing prosthetic hand functionality.
• This approach offers a more intuitive and efficient control scheme for users with prosthetic limbs.
• The findings suggest a promising direction for developing advanced prosthetic devices that mimic natural human movement.