Human Collaborative Control of Lower-Limb Prosthesis Based on Game Theory and Fuzzy Approximation

Area of Science:

• Biomedical Engineering
• Robotics
• Human-Computer Interaction

Background:

• Prosthetic users experience discomfort and tissue damage due to pressure from robotic leg prostheses.
• Existing robotic prostheses lack adaptive control to manage interaction forces effectively.

Purpose of the Study:

• To develop a human-robot collaborative control scheme for robotic prostheses.
• To minimize interaction torque and pressure on the residual limb while preserving prosthesis trajectory.
• To enhance user comfort and reduce the risk of degenerative tissue ulceration.

Main Methods:

• A novel human-robot collaborative control scheme was designed, treating residual limb pressure as interaction force.
• Trajectory optimization using a dual-agent game control scheme under a cooperative framework.
• A fuzzy logic system was implemented to improve trajectory tracking accuracy for unknown dynamic parameters.

Main Results:

• Experiments with two amputee participants demonstrated significant reduction in interaction torque.
• Minimal trajectory tracking error was maintained during prosthesis operation.
• The control scheme effectively self-adjusted control weight to minimize pressure.

Conclusions:

• The proposed human-robot interactive control scheme successfully reduces interaction torque in robotic leg prostheses.
• This approach enhances user comfort and safety by minimizing tissue pressure.
• The technology holds potential for improving the dexterity and usability of leg prostheses for amputees.