Timing of intermittent torque control with wire-driven gait training robot lifting toe trajectory for trip avoidance

Area of Science:

• Robotics in Rehabilitation
• Biomechanics of Human Locomotion
• Gait Analysis and Training

Background:

• Gait training robots aid in modifying gait patterns and reducing trip risks.
• Efficient gait training benefits from reduced robot assistance duration.
• Optimal timing for robotic intervention to enhance toe clearance remains unclear.

Purpose of the Study:

• To investigate the effect of intermittent robotic control timing on toe clearance during gait.
• To optimize knee flexion torque application during the swing phase for improved gait.
• To develop a non-time-dependent parameter for adaptive gait robot control.

Main Methods:

• A wire-driven gait training robot applying knee flexion torque was designed.
• Intermittent control strategies were tested at four distinct swing phase time points.
• Torque control timing was determined using hip, knee, and ankle angle data for adaptability.

Main Results:

• Applying knee flexion torque at the onset of toe lift significantly increased toe clearance.
• This intervention proved effective across the entire swing phase.
• The developed timing detection method adapted to variations in gait speed.

Conclusions:

• The timing of robotic intervention is critical for enhancing gait parameters like toe clearance.
• Initiating knee flexion torque at toe-off is an effective strategy for gait training robots.
• Adaptive, non-time-dependent control parameters improve robot functionality for gait modification.