Unilateral Ankle Exoskeleton Assistance Reshapes Gait: Temporal Parameters, Load Distribution, and Inter-Limb...

Area of Science:

• Biomechanics and Rehabilitation Engineering
• Human-Exoskeleton Interaction
• Gait Analysis

Background:

• Wearable exoskeletons aid gait rehabilitation and enhance locomotion.
• Limited systematic research exists on how exoskeleton assistance impacts gait parameters.

Purpose of the Study:

• To investigate the effects of assistance timing and magnitude on gait parameters using a unilateral ankle exoskeleton.
• To analyze temporal parameters, ground reaction forces, and inter-limb symmetry.
• To explore the influence of walking speed and reverse-order testing.

Main Methods:

• Twenty-two healthy participants tested nine personalized assistance profiles (three peak times x three peak torques).
• Analysis included temporal gait parameters, vertical ground reaction forces, and inter-limb symmetry indices.
• Investigated walking speed effects and necessity of reverse-order testing.

Main Results:

• Peak assistance timing significantly modulated most gait parameters, especially with higher torque.
• Later peak timing altered load-bearing, prolonging single-support on the assisted limb and reducing impact on the unassisted limb.
• Peak torque showed varied effects depending on timing; reverse-order testing and walking speed had minimal impact on symmetry.

Conclusions:

• Unilateral ankle exoskeleton assistance can strategically modulate gait parameters and redistribute lower-limb loading.
• Findings offer guidance for designing personalized gait training and assistance strategies.
• Exoskeleton assistance timing and magnitude are crucial for effective gait modulation.