A Rigid-Flexible Coupled Lower Limb Exoskeleton for Enhancing Load-Bearing Ambulation

Area of Science:

• Robotics
• Biomechanics
• Human Augmentation

Background:

• Lower limb exoskeletons aim to enhance human functionality.
• A key challenge is improving load capacity while minimizing metabolic cost.
• Existing designs often struggle to balance these competing requirements.

Purpose of the Study:

• To present a novel lower limb exoskeleton integrating rigid and flexible structures.
• To evaluate the exoskeleton's load transfer capabilities at the hip joint.
• To assess the reduction in metabolic costs with and without active assistance.

Main Methods:

• The study utilized a novel rigid-soft coupled lower limb exoskeleton design.
• Load transfer experiments were conducted with 10 kg and 15 kg loads during static standing and dynamic walking.
• Metabolic cost experiments were performed comparing exoskeleton-free (NE), assistance OFF (Assist OFF), and assistance ON (Assist ON) modes with a 15 kg load.

Main Results:

• Static load transfer rates reached 90.48% (10 kg) and 69.70% (15 kg).
• Dynamic walking load transfer rates were 62.07% (10 kg) and 43.69% (15 kg).
• Metabolic costs were reduced by 8.3% (Assist OFF) and 21.61% (Assist ON) compared to NE. Assist ON further reduced costs by 13.22% compared to Assist OFF.

Conclusions:

• The rigid-soft coupled exoskeleton demonstrates significant load transfer capabilities.
• The device effectively reduces metabolic costs during weight-bearing tasks.
• This technology holds potential for enhancing human performance in activities requiring load carriage.