Abstract
This paper presents a novel methodology for estimating the gait phase of human walking through a simple sensory apparatus. Three subsystems are combined: a primary phase estimator based on adaptive oscillators, a desired gait event detector and a phase error compensator. The estimated gait phase is expected to linearly increase from 0 to 2\(\pi \) rad in one stride and remain continuous also when transiting to the next stride. We designed two experimental scenarios to validate this gait phase estimator, namely treadmill walking at different speeds and free walking. In the case of treadmill walking, the maximum phase error at the desired gait events was found to be 0.155 rad, and the maximum phase difference between the end of the previous stride and beginning of the current stride was 0.020 rad. In the free walking trials, phase error at the desired gait event was never larger than 0.278 rad. Our algorithm outperformed against two other benchmarked methods. The good performance of our gait phase estimator could provide consistent and finely tuned assistance for an exoskeleton designed to augment the mobility of patients.
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Acknowledgments
This work was supported by the EU within the CYBERLEGs Project (FP7-ICT-2011-2.1 Grant Agreement #287894), by Fondazione Pisa within the IUVO Project (prog. 154/11).
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This is one of several papers published in Autonomous Robots comprising the “Special Issue on Assistive and Rehabilitation Robotics”.
Marco Cempini was with The BioRobotics Institute, Scuola Superiore Sant’Anna, 56025 Pisa, Italy when coauthoring this work.
Tingfang Yan and Andrea Parri contributed equally to this work.
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Yan, T., Parri, A., Ruiz Garate, V. et al. An oscillator-based smooth real-time estimate of gait phase for wearable robotics. Auton Robot 41, 759–774 (2017). https://doi.org/10.1007/s10514-016-9566-0
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DOI: https://doi.org/10.1007/s10514-016-9566-0