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
Design of a Biologically Inspired Water-Walking Robot Powered by Artificial Muscle
The agile and power-efficient locomotion of a water strider has inspired many water-walking devices. These bioinspired water strider robots generally adopt a DC motor to create a sculling trajectory of the driving leg. These robots are, thus, inevitably heavy with many supporting legs decreasing the velocity of the robots. There have only been a few attempts to employ smart materials despite their advantages of being lightweight and having high power densities. This paper proposes an artificial muscle-based water-walking robot capable of moving forward and turning with four degrees of freedom. A compliant amplified shape memory alloy actuator (CASA) used to amplify the strain of a shape memory alloy wire enables a wide sculling motion of the actuation leg with only four supporting legs to support the entire weight of the robot. Design parameters to increase the actuation strain of the actuator and to achieve a desired swing angle (80°) are analyzed. Finally, experiments to measure the forward speed and angular velocities of the robot are carried out to compare with other robots. The robot weighs only 0.236 g and has a maximum and average speed of 1.56, 0.31 body length per second and a maximum and average angular velocity of 145.05°/s and 14.72°/s.
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- NSF-PAR ID:
- 10338004
- Date Published:
- Journal Name:
- Micromachines
- Volume:
- 13
- Issue:
- 4
- ISSN:
- 2072-666X
- Page Range / eLocation ID:
- 627
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract W (i.e., electrical energy input of 4.22 ± 0.06J . The consistency and robustness of the snap‐through actuator response is experimentally validated through cyclical testing (580 cycles). The compact and fast‐responding properties of the soft bistable actuator allow it to be used as an artificial muscle for shape‐reconfigurable soft robots capable of multiple modes of SMA‐powered locomotion. This is demonstrated by creating three soft robots, including a reconfigurable amphibious robot that can walk on land and swim in water, a jumping robot (multimodal crawler) that can crawl and jump, and a caterpillar‐inspired rolling robot that can crawl and roll. -
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.3390/mi13040627
