Equilibrium Conformation of a Novel Cable-Driven Snake-Arm Robot under External Loads

Area of Science:

• Robotics
• Mechanical Engineering
• Control Systems

Background:

• Snake-arm robots offer high dexterity in confined spaces.
• Existing designs often face challenges in precise motion control and kinematic modeling.
• Cable-driven mechanisms present opportunities for lightweight and flexible robotic systems.

Purpose of the Study:

• To propose a novel cable-driven snake-arm robot utilizing an anti-parallelogram mechanism.
• To establish the kinematics and simplify the actuator-to-joint space mapping.
• To develop and validate a static model for analyzing robot conformation under external forces.

Main Methods:

• An approximate cylindrical rolling joint based on the anti-parallelogram mechanism was designed.
• Kinematics were established, simplifying motion through bending decoupling.
• A static model was derived using the principle of minimum potential energy and Taylor expansion for cable constraints.
• A prototype was built and tested for free bending and external load experiments.

Main Results:

• A novel multi-DOF cable-driven snake-arm robot was successfully developed.
• Simplified kinematic mapping and bending decoupling were achieved.
• The static model accurately predicted robot conformation under external forces, validated by prototype experiments.

Conclusions:

• The proposed anti-parallelogram mechanism enables a feasible and controllable cable-driven snake-arm robot.
• The simplified kinematic and static models are effective for analyzing robot behavior.
• The developed prototype confirms the practical applicability of the design and models.