Evaluating Gait Symmetry with a Smart Robotic Walker: A Novel Approach to Mobility Assessment
Mahdi Chalaki, Abed Soleymani, Xingyu Li, Vivian Mushahwar, Mahdi Tavakoli
TL;DR
The paper tackles gait asymmetry in populations affected by aging, stroke, or limb differences by deploying a Smart Walker that records interaction-torque signals and applies a seasonal-trend decomposition to extract stride-level patterns and a symmetry index. It introduces an MSTL-based framework to estimate stride durations and define the symmetry index, with the SA index given by $SA = (45° - arctan(X_{left}/X_{right})) * (100%/90°)$, and demonstrates an 84.9% accuracy in identifying asymmetric gait in controlled experiments. It further shows clustering of gait patterns via PCA and Gaussian Mixture Models, illustrating potential rehabilitation pathways through a simulated improvement trajectory. Overall, the approach enables real-world, continuous gait monitoring and supports targeted, personalized interventions using assistive robotics data.
Abstract
Gait asymmetry, a consequence of various neurological or physical conditions such as aging and stroke, detrimentally impacts bipedal locomotion, causing biomechanical alterations, increasing the risk of falls and reducing quality of life. Addressing this critical issue, this paper introduces a novel diagnostic method for gait symmetry analysis through the use of an assistive robotic Smart Walker equipped with an innovative asymmetry detection scheme. This method analyzes sensor measurements capturing the interaction torque between user and walker. By applying a seasonal-trend decomposition tool, we isolate gait-specific patterns within these data, allowing for the estimation of stride durations and calculation of a symmetry index. Through experiments involving 5 experimenters, we demonstrate the Smart Walker's capability in detecting and quantifying gait asymmetry by achieving an accuracy of 84.9% in identifying asymmetric cases in a controlled testing environment. Further analysis explores the classification of these asymmetries based on their underlying causes, providing valuable insights for gait assessment. The results underscore the potential of the device as a precise, ready-to-use monitoring tool for personalized rehabilitation, facilitating targeted interventions for enhanced patient outcomes.
