Biohybrid Tendons Enhance the Power-to-Weight Ratio and Modularity of Muscle-Powered Robots

Area of Science:

• Bioengineering
• Robotics
• Biomaterials

Background:

• Traditional biohybrid robots use muscle actuators directly on skeletons, limiting design flexibility.
• Native musculoskeletal systems utilize tendons for efficient force transmission between muscles and skeletons.

Purpose of the Study:

• To design and validate a biohybrid muscle-tendon unit inspired by native musculoskeletal architecture.
• To enhance the performance and efficiency of biohybrid robots through improved actuator design.

Main Methods:

• Developed a mathematical model of the muscle-tendon-skeleton interface.
• Engineered muscle actuators coupled with tough hydrogel tendons.
• Tuned tendon stiffness, pre-tension, and skeleton stiffness to optimize performance.
• Assessed fatigue characteristics over 7000 cycles.

Main Results:

• Achieved an approximately 11-fold improvement in the power-to-weight ratio of muscle-tendon units.
• Demonstrated optimized actuator performance through tuning of tendon and skeleton properties.
• Validated the durability of the biohybrid actuators over extensive cycling.

Conclusions:

• The developed muscle-tendon unit offers a robust and efficient approach for biohybrid robot design.
• This biomimetic strategy enhances modularity and efficiency in biohybrid robotic systems.
• The findings pave the way for advanced biohybrid robots with improved performance characteristics.