Design and Testing of a Prosthetic Foot With Interchangeable Custom Springs for Evaluating Lower Leg Trajectory Error, an Optimization Metric for Prosthetic Feet
An experimental prosthetic foot intended for evaluating a novel design objective is presented. This objective, called the lower leg trajectory error (LLTE), enables the optimization of passive prosthetic feet by modeling the trajectory of the shank during single support for a given prosthetic foot a...
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| Format: | Article |
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ASME International
2019
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| Online Access: | http://hdl.handle.net/1721.1/120084 https://orcid.org/0000-0002-1680-5108 https://orcid.org/0000-0002-2940-2383 https://orcid.org/0000-0002-4151-0889 |
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| author | Brett Johnson, W. Major, Matthew J. Prost, Victor Olesnavage, Kathryn Winter, Amos G. |
| author2 | Massachusetts Institute of Technology. Department of Mechanical Engineering |
| author_facet | Massachusetts Institute of Technology. Department of Mechanical Engineering Brett Johnson, W. Major, Matthew J. Prost, Victor Olesnavage, Kathryn Winter, Amos G. |
| author_sort | Brett Johnson, W. |
| collection | MIT |
| description | An experimental prosthetic foot intended for evaluating a novel design objective is presented. This objective, called the lower leg trajectory error (LLTE), enables the optimization of passive prosthetic feet by modeling the trajectory of the shank during single support for a given prosthetic foot and selecting design variables that minimize the error between this trajectory and able-bodied kinematics. A light-weight, fully characterized test foot with variable ankle joint stiffness was designed to evaluate the LLTE. The test foot can replicate the range of motion of a physiological ankle over a range of different ankle joint stiffnesses. The test foot consists of a rotational ankle joint machined from acetal resin, interchangeable U-shaped nylon springs that range from 1.5 N· m/deg to 24 N· m/deg, and a flexible nylon forefoot with a bending stiffness of 16 N·m2. The U-shaped springs were designed to support a constant moment along their length to maximize strain energy density; this feature was critical in creating a high-stiffness and highrange of motion ankle. The design performed as predicted during mechanical and in vivo testing, and its modularity allowed us to rapidly vary the ankle joint stiffness. Qualitative feedback from preliminary testing showed that this design is ready for use in large scale clinical trials to further evaluate the use of the LLTE as an optimization objective for passive prosthetic feet. |
| first_indexed | 2024-09-23T08:07:29Z |
| format | Article |
| id | mit-1721.1/120084 |
| institution | Massachusetts Institute of Technology |
| last_indexed | 2024-09-23T08:07:29Z |
| publishDate | 2019 |
| publisher | ASME International |
| record_format | dspace |
| spelling | mit-1721.1/1200842022-09-30T07:41:59Z Design and Testing of a Prosthetic Foot With Interchangeable Custom Springs for Evaluating Lower Leg Trajectory Error, an Optimization Metric for Prosthetic Feet Brett Johnson, W. Major, Matthew J. Prost, Victor Olesnavage, Kathryn Winter, Amos G. Massachusetts Institute of Technology. Department of Mechanical Engineering Prost, Victor Olesnavage, Kathryn Winter, Amos G. An experimental prosthetic foot intended for evaluating a novel design objective is presented. This objective, called the lower leg trajectory error (LLTE), enables the optimization of passive prosthetic feet by modeling the trajectory of the shank during single support for a given prosthetic foot and selecting design variables that minimize the error between this trajectory and able-bodied kinematics. A light-weight, fully characterized test foot with variable ankle joint stiffness was designed to evaluate the LLTE. The test foot can replicate the range of motion of a physiological ankle over a range of different ankle joint stiffnesses. The test foot consists of a rotational ankle joint machined from acetal resin, interchangeable U-shaped nylon springs that range from 1.5 N· m/deg to 24 N· m/deg, and a flexible nylon forefoot with a bending stiffness of 16 N·m2. The U-shaped springs were designed to support a constant moment along their length to maximize strain energy density; this feature was critical in creating a high-stiffness and highrange of motion ankle. The design performed as predicted during mechanical and in vivo testing, and its modularity allowed us to rapidly vary the ankle joint stiffness. Qualitative feedback from preliminary testing showed that this design is ready for use in large scale clinical trials to further evaluate the use of the LLTE as an optimization objective for passive prosthetic feet. 2019-01-16T16:02:15Z 2019-01-16T16:02:15Z 2018-03 2017-12 2019-01-11T16:19:51Z Article http://purl.org/eprint/type/JournalArticle 1942-4302 http://hdl.handle.net/1721.1/120084 Prost, Victor et al. “Design and Testing of a Prosthetic Foot With Interchangeable Custom Springs for Evaluating Lower Leg Trajectory Error, an Optimization Metric for Prosthetic Feet.” Journal of Mechanisms and Robotics 10, 2 (March 2018): 021010 © 2018 ASME https://orcid.org/0000-0002-1680-5108 https://orcid.org/0000-0002-2940-2383 https://orcid.org/0000-0002-4151-0889 http://dx.doi.org/10.1115/1.4039342 Journal of Mechanisms and Robotics Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use. application/pdf ASME International ASME |
| spellingShingle | Brett Johnson, W. Major, Matthew J. Prost, Victor Olesnavage, Kathryn Winter, Amos G. Design and Testing of a Prosthetic Foot With Interchangeable Custom Springs for Evaluating Lower Leg Trajectory Error, an Optimization Metric for Prosthetic Feet |
| title | Design and Testing of a Prosthetic Foot With Interchangeable Custom Springs for Evaluating Lower Leg Trajectory Error, an Optimization Metric for Prosthetic Feet |
| title_full | Design and Testing of a Prosthetic Foot With Interchangeable Custom Springs for Evaluating Lower Leg Trajectory Error, an Optimization Metric for Prosthetic Feet |
| title_fullStr | Design and Testing of a Prosthetic Foot With Interchangeable Custom Springs for Evaluating Lower Leg Trajectory Error, an Optimization Metric for Prosthetic Feet |
| title_full_unstemmed | Design and Testing of a Prosthetic Foot With Interchangeable Custom Springs for Evaluating Lower Leg Trajectory Error, an Optimization Metric for Prosthetic Feet |
| title_short | Design and Testing of a Prosthetic Foot With Interchangeable Custom Springs for Evaluating Lower Leg Trajectory Error, an Optimization Metric for Prosthetic Feet |
| title_sort | design and testing of a prosthetic foot with interchangeable custom springs for evaluating lower leg trajectory error an optimization metric for prosthetic feet |
| url | http://hdl.handle.net/1721.1/120084 https://orcid.org/0000-0002-1680-5108 https://orcid.org/0000-0002-2940-2383 https://orcid.org/0000-0002-4151-0889 |
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