Light-Driven Linear Inchworm Motor Based on Liquid Crystal Elastomer Actuators Fabricated with Rubbing Overwriting

Area of Science:

• Materials Science
• Robotics
• Optics

Background:

• Linear displacement is crucial for robotics and scientific instrumentation.
• Conventional linear motors rely on rotary drives, pressure, electromagnetic forces, or material shape changes (e.g., piezoelectrics, shape-memory materials).

Purpose of the Study:

• To present a novel centimeter-scale linear inchworm motor powered by light.
• To demonstrate the use of liquid crystal elastomer (LCE) accordion-like actuators for light-driven motion.

Main Methods:

• Fabrication of LCE actuators using the rubbing overwriting technique on elastomer films with patterned alignment.
• Utilizing a scanned green laser beam to induce traveling deformations in LCE actuators.
• Employing a gripper coupled to a shaft via friction to achieve linear movement.

Main Results:

• The prototype linear motor achieved an average speed in the order of millimeters per second.
• Demonstrated that LCE actuators with limited strain can drive complex mechanisms for large displacements.
• Showcased the potential for scaling down to sub-millimeter sizes.

Conclusions:

• Light-driven LCE actuators offer a viable method for creating inchworm motors.
• This technology enables remote control and power supply via light, advantageous for various applications.
• The developed motor overcomes the strain limitations of individual actuators for achieving macro-scale displacements.