Comparative analysis of models capturing foot trajectory complexity across ambulation modes: application to robotic prosthesesShow others and affiliations
2026 (English)In: Applied intelligence (Boston), ISSN 0924-669X, E-ISSN 1573-7497, Vol. 56, no 9, article id 313Article in journal (Refereed) Published
Abstract [en]
Accurate prediction of foot pattern throughout various terrains is essential for achieving stable and adaptive control in powered lower-limb prostheses. In this study, a range of predictive models, including regression-based approaches, ensemble machine learning methods, and recurrent neural networks (RNNs), were systematically compared to determine their capability in generating oscillatory gait signals from tibial angular position while walking on varied terrain. The training and testing data were collected from ten healthy individuals while level-ground walking, ascending and descending stairs. Statistical models had poor accuracy and generalization, while ensemble methods (Gradient Boosting, Histogram-Based Gradient Boosting, and eXtreme Gradient Boosting) had moderate performance but remained sensitive to outliers and inter-subject variation. In contrast, recurrent architectures, i.e., long short-term memory networks (LSTM), had the highest predictive accuracy, with a mean correlation of 0.88, and a low root mean square error of 0.09 rad. Although the LSTM-based method provided slightly lower accuracy than some of the control methods inspired by the central pattern generators in the literature, it required only prosthesis-embedded sensors, avoiding the need for sensors on the intact or residual limb. Moreover, the compact network size and low computational load make it well-suited for embedded deployment, reducing cost, power consumption, and user burden. These findings place RNN-based approaches in line with ongoing research trends toward dynamic pattern generator–inspired controllers, offering robust, volitional-like control while maintaining practicality for real-world implementation.
Place, publisher, year, edition, pages
Springer , 2026. Vol. 56, no 9, article id 313
Keywords [en]
Powered prosthesis, Gait prediction, Oscillatory bio-signals, Regression models, Ensemble learning, Recurrent neural networks
National Category
Electrical Engineering, Electronic Engineering, Information Engineering Computer and Information Sciences
Research subject
Machine Learning
Identifiers
URN: urn:nbn:se:ltu:diva-118885DOI: 10.1007/s10489-026-07315-wISI: 001795359200001Scopus ID: 2-s2.0-105042046810OAI: oai:DiVA.org:ltu-118885DiVA, id: diva2:2082848
Note
Funder: Universiti Malaya special research grant (BKS004-2023);
Fulltext license: CC BY-NC-ND
2026-07-012026-07-012026-07-01Bibliographically approved