A Bio-Inspired Arched Foot with Individual Toe Joints and Plantar Fascia

Area of Science:

• Biomimetics
• Biomechanics
• Robotics

Background:

• Human foot anatomy features complex arches and multiple joints enabling versatile movement.
• Existing bio-inspired foot designs often lack the full range of motion and flexibility of a natural human foot.

Purpose of the Study:

• To design and test a novel triple-arched foot incorporating biomimetic features like individual toe and midfoot joints.
• To analyze the mechanical properties and range of motion of the artificial foot in comparison to human feet.

Main Methods:

• Utilized adult female bone data to create a CAD model for accurate anatomical replication.
• Developed an analytical model to establish relationships between arch stiffness and optimize design parameters.
• Conducted experimental tests to measure vertical arch stiffness, range of motion, and ground contact patterns.

Main Results:

• The triple-arched foot demonstrated flexibility with up to 12 mm vertical deflection.
• Achieved a vertical arch stiffness of 76 N/mm, comparable to human feet.
• Replicated human foot range of motion in dorsi-plantarflexion, inversion-eversion, and abduction-adduction, with a three-point ground contact.

Conclusions:

• The biomimetic triple-arched foot successfully replicates key biomechanical features of the human foot.
• Individual toe joints allow for natural pronation, enhancing forefoot adaptability.
• This design represents a significant advancement in bio-inspired foot prosthetics and robotics.