Shape memory meta-laminar jamming actuators fabricated by 4D printing.

Area of Science:

• Robotics and Materials Science
• Soft Robotics
• Smart Materials

Background:

• Laminar jamming (LJ) enables the transition from rigid to soft robotic systems.
• Conventional LJ actuators require continuous negative air pressure for operation.
• There is a need for more sustainable and versatile soft robotic actuators.

Purpose of the Study:

• To introduce a novel conceptual design of meta-laminar jamming (MLJ) actuators.
• To utilize polyurethane shape memory polymer (SMP) meta-structures fabricated by 4D printing (4DP).
• To demonstrate MLJ actuators that function as soft/hard robots without continuous negative air pressure.

Main Methods:

• Fabrication of SMP meta-structures (circle, rectangle, diamond, auxetic shapes) using 4D printing.
• Evaluation of mechanical properties through three-point bending and compression tests.
• Investigation of shape memory effects (SMEs) and shape recovery via hot air programming and negative air pressure.

Main Results:

• MLJ actuators with auxetic meta-structure cores exhibited superior contraction and bending performance.
• Achieved 100% shape recovery after stimulation in MLJ actuators.
• Demonstrated shape recovery and shape locking capabilities with zero input power, holding up to 200 g.

Conclusions:

• The developed sustainable MLJ actuators offer a novel approach to soft robotics.
• These actuators eliminate the need for continuous negative air pressure, enhancing practicality.
• The versatility in lifting and gripping diverse objects showcases potential applications as end-effectors and grippers.