Print Email Facebook Twitter Design and evaluation of the pneumatic leg prosthesis ERiK to assist elderly amputees with sit-down and stand-up movements Title Design and evaluation of the pneumatic leg prosthesis ERiK to assist elderly amputees with sit-down and stand-up movements Author Vallery, H. (TU Delft Biomechatronics & Human-Machine Control; Erasmus MC) Lachmann, F. (TU Delft Biomechatronics & Human-Machine Control) van der Helm, S.G. (Student TU Delft) Pennycott, A. (TU Delft Biomechatronics & Human-Machine Control) Smit, G. (TU Delft Medical Instruments & Bio-Inspired Technology) Date 2023 Abstract Standing up using one leg is a challenging task for those with a transfemoral amputation, particularly for elderly users with a low activity level. Active prostheses are generally not accessible to this group and available passive prostheses do not support standing up. This article presents the design and evaluation of the “Energy Restoring Intelligent Knee” (ERiK), which stores energy during sit-down in a pneumatic cylinder and returns it during stand-up. We hypothesized that the system would reduce the time needed to perform transitions and also enable higher load sharing by the prosthetic leg. However, the results of an experimental study with seven participants with transfemoral amputation contradict these hypotheses: the participants could neither move faster nor make more use of the prosthetic leg to share their body weight during transitions. We observed that a major obstacle to the useful functionality of the leg was the absence of ankle dorsiflexion – the foot tended to slip during stand-up initiation, such that only low pre-pressures and therefore support levels could be set. The rather binary action of the pneumatics also complicated movement initiation. The lessons learned from this study may be helpful to those seeking to create better designs in the future. Subject Knee exoprosthesissit-to-standlightweight pneumatic actuatortransfemoral amputation To reference this document use: http://resolver.tudelft.nl/uuid:8d484c86-5071-4ad8-867d-8501f55dcc71 DOI https://doi.org/10.1017/wtc.2023.8 ISSN 2631-7176 Source Wearable Technologies, 4 Part of collection Institutional Repository Document type journal article Rights © 2023 H. Vallery, F. Lachmann, S.G. van der Helm, A. Pennycott, G. Smit Files PDF design_and_evaluation_of_ ... ements.pdf 1.17 MB Close viewer /islandora/object/uuid:8d484c86-5071-4ad8-867d-8501f55dcc71/datastream/OBJ/view