Changes in the Determinism of the Gait Dynamics with the Intervention of a Robotic Walker

Abstract

(1) Robotic walkers have gradually been developed over the last decade, and their use has caused changes in gait. However, detailed gait analyses during robotic walker-assisted walking have not been performed. In this study, we aim to identify the changes in determinism of gait dynamics owing to the intervention of a robotic walker. (2) Eleven healthy subjects participated in walking experiments under normal walking, rollator-assisted walking, and robotic walker-assisted walking conditions. We analyzed the measured trunk acceleration to derive the gait parameters, local scaling exponent (LSE, from correlation sum), and percentage of determinism (%DET, from recurrence plot). (3) The walking speed during rollator-assisted walking was significantly lower than that during robotic walker-assisted walking. Changes in the shape of the LSE along the anterior–posterior direction revealed the influence of the robotic walker at an individual level. The changes in %DET along the anterior–posterior direction were also significantly different between normal walking and robotic walker-assisted walking. (4) The rollator decreased the walking speed in comparison to normal walking. The changed LSE and reduced %DET imply reduced deterministic patterns and disturbance to the gait dynamics. The robotic walker only affects the gait dynamics in the anterior–posterior direction. Furthermore, the burden on the subjects was reduced during robotic walker-assisted walking.

Keywords

• nonlinear time series analysis
• robotic walker-assisted walking
• gait analysis
• changes in the determinism of gait dynamics