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Updated: Feb 24, 2026
11:16
Engineering Platform and Experimental Protocol for Design and Evaluation of a Neurally-controlled Powered Transfemoral Prosthesis
Published on: July 22, 2014
16.7K
Modeling and control of a transfemoral prosthesis embedding two infinitely variable transmissions
Summary
This study introduces a novel transfemoral prosthesis actuation concept using a single motor and mechanical components to manage power flow, reducing motor strain during locomotion. Simulations confirm its effectiveness in filtering load power and highlight the need for mechanical efficiency.
Area of Science:
- Biomedical Engineering
- Robotics
- Biomechanics
Background:
- Transfemoral prostheses aim to restore natural gait.
- Existing designs often struggle with managing power fluctuations during different locomotion phases.
- A need exists for more efficient and robust actuation systems.
Purpose of the Study:
- To present an original actuation concept for transfemoral prostheses.
- To develop and simulate a closed-loop controller for this novel actuation system.
- To evaluate the system's ability to manage power flow and reduce motor load.
Main Methods:
- A novel actuation mechanism combining a single motor, compliant element, mechanical differential, and two transmissions.
- Development of a preliminary closed-loop controller.
- Simulations of the prosthesis controller for level-ground walking, stair ascent, and stair descent.
Main Results:
- The proposed actuation concept effectively manages bidirectional mechanical power flow (energy production and dissipation).
- The system successfully filters sharp load power fluctuations experienced by the motor.
- Simulation results demonstrate the controller's viability for various locomotion tasks.
Conclusions:
- The novel actuation principle shows promise for transfemoral prostheses by mitigating motor power fluctuations.
- Maximizing the mechanical efficiency of all components is crucial for optimal performance.
- Further research and development are warranted for practical implementation.
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