Remotely actuated programmable self-folding origami strings using magnetic induction heating.

Area of Science:

• Materials Science
• Robotics
• Micro-engineering

Background:

• Manual folding of planar structures into volumetric objects is impractical at sub-centimeter scales.
• Smart materials offer solutions for automated folding but are limited by complexity and sequence control.
• Existing methods often require direct contact or are restricted in material variety and folding sequences.

Purpose of the Study:

• To propose and demonstrate a method for sequential self-folding of millimeter-scale origami using magnetic induction heating.
• To develop a magneto-thermal model for designing and predicting the folding sequence of self-folding structures, including overhand knots.
• To validate the methodology through the successful self-folding of various complex structures.

Main Methods:

• Utilized magnetic induction heating at kHz frequencies and 3.2 mT for remote, sequential folding.
• Developed a magneto-thermal model to predict and design folding sequences.
• Optimized surface, placement, and geometry of metal workpieces for controlled self-folding.

Main Results:

• Successfully demonstrated sequential self-folding of millimeter-scale origami structures.
• Validated the method with diverse examples: a croissant, a box, a Mimosa pudica leaf mimic, and an overhand knot.
• Achieved remote and tetherless self-folding within constrained environments.

Conclusions:

• The proposed method enables precise, sequential self-folding of miniature origami structures.
• The magneto-thermal model aids in the design and prediction of complex folding behaviors.
• This approach holds significant potential for developing miniature self-folding origami robots.