The Design and Testing of a PEA Powered Ankle Prosthesis Driven by EHA

Area of Science:

• Biomedical Engineering
• Robotics
• Biomechanics

Background:

• Serial elastic actuators (SEAs) show potential in reducing power and energy use in ankle prostheses.
• Optimizing actuation concepts is crucial for maximizing the effectiveness of power sources in prosthetic devices.

Purpose of the Study:

• To propose an optimized design, mechanical structure, control strategy, and experimental validation for a new powered ankle-foot prosthesis.
• To investigate the feasibility of a parallel elastic actuator (PEA) concept for ankle prostheses.

Main Methods:

• Developed a parallel elastic actuator (PEA) using an electro-hydrostatic actuator (EHA) and a unidirectional parallel spring.
• Created a dynamic model of the PEA prosthesis based on biological data to determine optimal spring parameters.
• Designed and implemented the hydraulic, mechanical, and control systems for the prosthesis.
• Conducted bench experiments to evaluate the prosthesis's performance.

Main Results:

• The designed powered ankle-foot prosthesis successfully met the biomechanical dynamics requirements.
• Experimental results validated the performance of the PEA actuation concept.
• Demonstrated the viability of electro-hydrostatic actuators (EHAs) as a power source and actuator in prosthetics.

Conclusions:

• The proposed parallel elastic actuator (PEA) design is effective for powered ankle-foot prostheses.
• Electro-hydrostatic actuators (EHAs) are feasible for prosthetic applications.
• This research offers innovative approaches for the development of advanced ankle-foot prostheses.