Biomimicry Inspired Robotic Cat Leg Fabrication through Subtractive Rapid Prototyping in Plywood

Abstract:

The development of a robotic cat leg inspired by biomimicry was executed with subtractive rapid prototyping technique. The design emulates the proportions and functions of a natural cat's hind leg, with the femur, tibia, and metatarsal scaled for relative precision. Plywood was selected as the principal material due to its lightweight and economical characteristics, making it appropriate for iterative prototyping. The manufacturing method entailed accurate 2D schematics converted into tangible components via CNC routing. The constructed robotic leg exhibited fundamental locomotor abilities, emulating the lifting, extending, and retracting motions characteristic of a cat's normal walk. Although the prototype demonstrated functionality, issues such as joint rigidity and material degradation underscored opportunities for enhancement. This study demonstrates the promise of subtractive prototyping in the development of biomimetic robotic systems and establishes a basis for future improvements in joint flexibility, material selection, and movement accuracy.

• Periodical: Engineering Headway (Volume 41)
• Pages: 47-61
• DOI: https://doi.org/10.4028/p-vq4Ihh
• Online since: July 2026
• Authors: S. Idhayaraja*, Ajithkumar Sitharaj, J. Pradeep Kumar
• Keywords: Biomimetic, CNC Routing, Locomotion Mechanism, Plywood, Robotic Cat Leg, Subtractive Rapid Prototyping

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