Soft robots struggle with terrestrial locomotion
due to their inherent lack of rigidity, specifically
along axes not in line with the direction of actuation
(side loads). We present a method for improved
stiffness in a 3D printed, tendon-driven soft actuator.
We show, both mathematically and experimentally, that
our method leads to improved stiffness to these side
loads. Additionally, we demonstrate the use of complex
tendon routing schemes to achieve various trajectories
with a single actuator morphology. Finally, we demonstrate
that these two tendon routing strategies lead to
improved locomotion speed and gait efficiency in a 3-
legged, 3D printed, soft robot.
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A Multimodal Climbing-Swimming Soft Robotic Lamprey
Here, we present a multimodal, lamprey-inspired, 3D printed soft fluidic robot/actuator based on an antagonistic pneunet architecture. The Pacific Lamprey is a unique fish which is able to climb wetted vertical surfaces using its suction-cup mouth and snake-like morphology. The continuum structure of these fish lends itself to soft robots, given their ability to form continuous bends. Additionally, the high gravimetric and volumetric power density attainable by soft actuators make them good candidates for climbing robots. Fluidic soft robots are often limited in the forces they can exert due to limitations on their actuation pressure. This actuator is able to operate at relatively high pressures (for soft robots) of 756 kPa (95 psig) with a −3 dB bandwidth of 2.23 Hz to climb at rates exceeding 18 cm/s. The robot is capable of progression on a vertical surface using a compliant microspine attachment as the functional equivalent of the lamprey’s more complex suction-cup mouth. The paper also presents the details of the 3D-printed manufacturing of this actuator/robot.
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- Award ID(s):
- 1935278
- PAR ID:
- 10385204
- Date Published:
- Journal Name:
- BATH/ASME 2022 Symposium on Fluid Power and Motion Control
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1115/FPMC2022-89984
