Matching the rich multimodality of natural organisms, i.e., the ability to transition between crawling and swimming, walking and jumping, etc., represents a grand challenge in the fields of soft and bio‐inspired robotics. Here, a multimodal soft robot locomotion using highly compact and dynamic bistable soft actuators is achieved. These actuators are composed of a prestretched membrane sandwiched between two 3D printed frames with embedded shape memory alloy (SMA) coils. The actuator can swiftly transform between two oppositely curved states and generate a force of 0.3 N through a snap‐through instability that is triggered after 0.2 s of electrical activation with an input power of 21.1 ± 0.32
Light has been recently intensively explored to power robots. However, most existing light‐driven robots have limited locomotion modalities, with constrained locomotion capabilities. A light‐powered soft robot with a bioinspired design is demonstrated, which can crawl on ground, squeeze its way through a small channel, and jump over a barrier. The arch‐shaped robot is made up of liquid crystal elastomer–carbon nanotube composite. When a light source with a power intensity of around 1.57 W cm−2is scanned over the surface of the robot, it deforms and crawls forward. With an increase in the light scanning speed, it can deform sufficiently to pass through a channel 25% lower than its body height. Subjected to light irradiation, it can also deform to a closed loop, gradually store elastic energy, and suddenly release it to jump over a wall or onto a step quickly, with a jumping distance around eight times its body length and jumping height around five times its body height. Mathematical models for quantitatively understanding the multimodal locomotion of this light‐powered soft robot are also presented.
more » « less- NSF-PAR ID:
- 10457133
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials Technologies
- Volume:
- 4
- Issue:
- 7
- ISSN:
- 2365-709X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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