A starfish robot based on soft and smart modular structure (SMS) actuated by SMA wires

Area of Science:

• Robotics
• Biomimetics
• Materials Science

Background:

• Starfish locomotion principles offer inspiration for novel robotic designs.
• Soft and smart materials enable advanced robotic functionalities.
• Controlling actuators like shape memory alloy wires is crucial for robotic performance.

Purpose of the Study:

• To design, fabricate, and test a starfish robot mimicking natural starfish locomotion.
• To develop and implement an adaptive regulation heating strategy for shape memory alloy actuators.
• To evaluate the robot's propulsion speed and efficiency in various aquatic environments.

Main Methods:

• Fabrication of smart modular structure (SMS) tentacles using soft and smart materials.
• Integration of shape memory alloy (SMA) wires for actuation within the SMS tentacles.
• Development of an adaptive regulation (AR) heating strategy based on SMA wire resistance.
• Establishment of a thermal dynamic model using the finite-segment method.
• Experimental testing of the starfish robot with varying control parameters.

Main Results:

• The starfish robot successfully propelled in semi-submerged and underwater conditions.
• The AR heating strategy effectively managed SMA wire temperature and bending range.
• Propulsion speeds achieved were significantly higher (at least an order of magnitude) than existing literature.
• The SMS tentacles demonstrated high-speed response actuation.

Conclusions:

• The developed starfish robot effectively mimics natural locomotion.
• The adaptive regulation strategy enhances the performance and safety of SMA actuators.
• This novel robotic design offers a promising platform for underwater exploration and other applications requiring efficient aquatic locomotion.