Development and Performance Verification of a Motorized Prosthetic Leg for Stair Walking.

Area of Science:

• Biomedical Engineering
• Robotics
• Mechanical Engineering

Background:

• Developing advanced prosthetic limbs is crucial for improving the mobility and quality of life for amputees.
• Mimicking natural human gait, especially during complex activities like stair climbing, remains a significant challenge in prosthetic design.

Purpose of the Study:

• To optimally design and evaluate the performance of a motorized prosthetic leg for effective stair walking.
• To integrate a DC motor for knee joint motion and a spring system for ankle joint torque, enhancing gait imitation.

Main Methods:

• Utilized a virtual product development process for designing a prosthetic leg with two degrees of freedom (knee and ankle).
• Employed topology optimization to reduce unnecessary mass and selected materials like aluminum alloy and 3D-printed nylon for specific components.
• Validated structural integrity using finite element analysis under various walking conditions.

Main Results:

• Achieved an optimal design for the motorized prosthetic leg, ensuring structural safety under defined boundary conditions derived from human walking data.
• Successfully synchronized the prosthetic knee's motion with normal human gait patterns using a Proportional-Derivative (PD) controller.
• Demonstrated the prosthetic leg's capability for improved stair walking performance.

Conclusions:

• The developed powered transfemoral prosthesis offers a viable solution for enhanced mobility in amputees, potentially aiding their rehabilitation process.
• The design principles and control strategies employed can be applied to the development of biped robots aiming to replicate human-like motion.