Photothermal and Magnetic Actuation of Multimodal PNIPAM Hydrogel-Based Soft Robots

Area of Science:

• Robotics
• Materials Science
• Biomimicry

Background:

• Soft robot motion is a key research area.
• Existing soft robots face challenges in mimicking biological motion.
• Novel materials are needed for advanced soft robot performance.

Purpose of the Study:

• To investigate the motion capabilities of soft robots using enhanced poly(N-isopropylacrylamide) (PNIPAM) hydrogels.
• To develop PNIPAM hydrogels with photothermal response properties for controllable deformation.
• To create and test various soft robot prototypes for complex tasks.

Main Methods:

• Optimized PNIPAM hydrogel formulation with molybdenum disulfide (MoS2) for photothermal response.
• Developed flytrap-inspired, hexapod crawling, and magnetically driven rolling soft robot prototypes.
• Systematically explored hydrogel motion characteristics through prototype testing.

Main Results:

• Achieved muscle-like controllable contraction and expansion in PNIPAM hydrogels.
• Demonstrated rapid opening-closing movements in a flytrap-inspired robot.
• Enabled stable directional crawling in a hexapod robot and multimodal movement (1.8 cm/s rolling, 1.5x obstacle surmounting) in a magnetic rolling robot.

Conclusions:

• Validated the potential of PNIPAM hydrogel-based soft robots for complex motion tasks.
• Provided insights into developing multimodal soft robotic systems.
• Paved the way for future innovations in adaptive and bio-inspired robotics.