Research on the Range of Stiffness Variation in a 2D Biomimetic Spinal Structure Based on Tensegrity Structures

Area of Science:

• Robotics and Mechanical Engineering
• Biomimetic Design
• Tensegrity Structures

Background:

• Biological spinal structures exhibit remarkable compliance and stiffness adaptability.
• Tensegrity structures offer unique mechanical properties, including compliance and load distribution.
• Variable stiffness mechanisms are crucial for advanced robotic applications requiring adaptability.

Purpose of the Study:

• To introduce a novel variable stiffness mechanism, the Spinal Biomimetic Two-Dimensional Tensegrity Structure (SBTDTS).
• To establish a method for determining the torsional stiffness of the SBTDTS.
• To optimize the SBTDTS for maximum stiffness ratio and compare its performance with existing mechanisms.

Main Methods:

• Bioinspiration from spinal structures integrated with T-Bar tensegrity design.
• Application of parallel mechanism theory to determine torsional stiffness.
• Utilizing Particle Swarm Optimization (PSO) for parameter optimization.
• Comparative analysis with Rotational Parallel Mechanisms (RAPRPM).

Main Results:

• A method for calculating SBTDTS torsional stiffness around a virtual rotational center was developed.
• Analysis revealed relationships between structural parameters and stiffness.
• PSO successfully identified optimal parameters maximizing the stiffness ratio (Kθ_time).
• The optimized SBTDTS demonstrated distinct advantages over RAPRPM under varying conditions.

Conclusions:

• The SBTDTS represents a novel and effective variable stiffness mechanism.
• The developed methodology enables precise stiffness determination and optimization.
• The bioinspired design and optimization strategy offer significant potential for advanced robotic systems.