Pneu-HTP based extrusion actuation in bio-inspired soft joint

Area of Science:

• Robotics
• Materials Science
• Biomimetics

Background:

• Traditional robotic joints often lack the compliance and dexterity of biological systems.
• Spider leg articulation offers a unique model for bio-inspired soft actuation.
• Pneumatic actuators provide inherent safety and adaptability for soft robotic applications.

Purpose of the Study:

• To design and model a novel pneumatic soft joint actuator inspired by spider leg mechanisms.
• To develop a mathematical model for pneumatic hyperelastic thin plate (Pneu-HTP) based extrusion actuation.
• To validate the proposed model through finite element analysis (FEA) simulations and experimental testing.

Main Methods:

• A novel pneumatic soft joint actuator was designed based on spider leg joint structure and actuation.
• A modeling method using pneumatic hyperelastic thin plates (Pneu-HTPs) was proposed for extrusion actuation.
• Mathematical models for parallel and angular extrusion actuation were derived.
• FEA simulations and experimental tests were conducted to evaluate model accuracy.

Main Results:

• The proposed Pneu-HTP model demonstrated high accuracy for parallel extrusion actuation with an average relative error of 9.27% and goodness-of-fit >99%.
• For angular extrusion actuation, the model achieved an average relative error of 12.5% and goodness-of-fit >99%.
• Actuating forces predicted by the model closely matched FEA simulation results for both parallel and rotational extrusion.

Conclusions:

• The developed Pneu-HTP based modeling method accurately predicts the behavior of pneumatic soft joint actuators.
• This approach offers a promising and reliable technique for the precise modeling of extrusion actuation in soft robotics.
• The bio-inspired design provides a foundation for developing more sophisticated and adaptable soft robotic systems.