Adaptive Prothesen

Development of concepts to adapt the dynamic behaviour of external lower limb prostheses

 

Background

Humans with amputations desire prosthesis, which compensate their lost limb in every situation. The application of mechatronic approaches led to a crucial progress in prosthetics in the last two decades. In the meantime extensions of functionality and a gain in comfort for the users were created by new prosthesis concepts. Nevertheless there still is a big potential for future developments to optimize effort and comfort for the user. Especially in dynamic situations of gait previous prosthesis are unable to handle these challenges.

Challenges and Potential

Dynamic gait situations are often negotiable challenges for amputees
Dynamic gait situations are often negotiable challenges for amputees

During gait, a lot of parameter changes their values. E.g. several individual muscle or groups of muscles will be activated and modify biomechanical kinematics, joint ankles and stiffness, etc.. For a long time, the technical mimicking of the gait was limited by imitating the necessary mechanical behavior for normal gait. In the last years mechatronic systems become prevalent impact. Current prostheses are able to generate specific torques in knee or ankle to support users in their intention. These Systems are aimed on daily situations, e.g. climbing stairs/ ramps up and down as well as regular gait on even ground.

Currently, there aren’t big research or development objectives on dynamic gait situations, e.g. fast walking on uneven ground, turning and cornering or stumbling. To satisfy the users’ requirements to overcome these situations in security is the potential which offers the opportunity of research.

Adaptive prosthetic shank with rotational torsion stiffness and foot alignment
Adaptive prosthetic shank with rotational torsion stiffness and foot alignment

Objective and approach

The goal of this DFG-founded project is to identify relevant degrees of freedom for dynamic gait situations. Therefore the varying of biomechanical parameter during the special situations will be examined. The results give the opportunity for developing concepts and components, which are able to support the user and deliver feeling of security, comfort and efficiency. In this proposal Blatchford Product Limited, UK (manufacturer of prostheses) and the Institute for Mechatronic Systems in Mechanical Engineering of TU Darmstadt bundle their experiences.

Funding

This project was funded by Deutsche Forschungsgemeinschaft

  • Cooperation IMS – Blatchford
  • Components of development