Bionic Technology in Prosthetics: Multi-Objective Optimization of a Bioinspired Shoulder-Elbow Prosthesis with...

Area of Science:

• Biomedical Engineering
• Robotics
• Biomechanics

Background:

• Upper-limb prostheses face challenges like limited dexterity, restricted workspace, and bulkiness, leading to high user abandonment.
• Proximal joint limitations (shoulder, elbow) significantly impact prosthetic functionality and user satisfaction.

Purpose of the Study:

• To develop a novel, bioinspired, and integrated prosthetic system to overcome existing limitations in upper-limb prostheses.
• To enhance prosthetic performance through advanced joint mechanisms and optimization techniques.

Main Methods:

• Designed a shoulder joint using an asymmetric 3-RRR spherical parallel mechanism (SPM) with embedded actuators.
• Developed an elbow joint actuated by low-voltage Shape Memory Alloy (SMA) springs.
• Utilized Multi-Objective Particle Swarm Optimization (MOPSO) to optimize workspace, dexterity, and joint torque.

Main Results:

• Achieved 85% coverage of the natural shoulder's workspace.
• Demonstrated structural integrity with a maximum von Mises stress of 3.4 MPa under a 40 N load.
• Obtained a sub-0.2 s response time for the SMA-driven elbow at 6 V and 6°/s, validating smooth, anthropomorphic motion.

Conclusions:

• The developed prosthetic system offers a lightweight, high-performance solution for upper-limb prosthetics.
• This framework lays the foundation for next-generation wearable robotics and bionic devices.
• Future work will integrate neural interfaces for intuitive prosthetic control.