An Energy-Based Personalized Gait Adjustment Approach for Individuals with Gait Abnormalities During Walking

This paper presents a novel energy-based gait adjustment approach for adapting assistance to individuals with different gait abnormalities to improve gait performance.

This paper first proposes a Lower-Limb Bidirectional Potential Energy Transmission (BPET) model combined the human leg and an elastic energy storage element (EESE). Then, the stiffness of the EESE is modeled based on the BPET model. A simplification model is derived using the least-squares method to obtain a personalized constant stiffness K, which can be utilized for personalized gait assistance. Finally, the BPET model based gait assistance module prototype was manufactured and evaluated in gait-adjustment experiments involving six healthy subjects with simulated gait abnormalities and one subject with cerebral palsy (CP). Nine indices were adopted to characterize gait performance.

In healthy subjects, module was associated with increases in lower-limb kinematic and spatial gait parameters. Under the different loading conditions, mean increases were observed in peak hip flexion (16.8% ± 6.5% and 17.3% ± 16.2%), hip range of motion (ROM, 16.4% ± 14.8% and 19.3% ± 6.9%), toe clearance (45.0% ± 53.5% and 61.5% ± 62.8%), step length (21.0% ± 14.7% and 22.9% ± 8.0%), and stride length (16.1% ± 14.0% and 20.9% ± 12.5%). Peak knee flexion increased in five of six subjects under each loading condition. In the CP subject, module increased peak hip flexion, hip joint ROM, toe clearance, step length, stride length, and peak knee flexion by 46.8%, 27.6%, 32.3%, 9.6%, 6.0%, and 10.7%, respectively. Across all subjects, temporal symmetry indices shifted toward the ideal value under module. Conclusion & Significance: This work provides preliminary evidence that personalized elastic assistance, governed by a user-specific model, may improve gait performance during rollator-assisted walking.