This paper presents a layering approach for the manufacturing of pneumatic soft actuators as a coalesced solution to the diverse array of existing fabrication methods. While most research groups have developed their own (often tedious) fabrication strategies for soft actuators, these methods are usually based on available equipment and project-specific design requirements, making them impractical for use in other laboratories. In contrast, the layered substrate approach enables repeatable production of highly-capable pneumatic actuators that can be easily customized to suit a variety of applications. Here we propose layering fiber-reinforced silicone on both sides of a thin pneumatic chamber to directionally constrain expansion. Similar in concept to the Venus flytrap, pressurization of the chamber causes the module to deform and expand where unrestrained. Strategic orientation and patterning of the fiber reinforcement layers results in multiple unique shear and bending capabilities upon pressurization. Combinations of multiple reinforced pneumatic units in series or parallel could match the capabilities of most soft pneumatic actuators, while requiring only simple, universal fabrication methods that may be replicated by other research groups.
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Vision-based FDM Printing for Fabricating Airtight Soft Actuators
Pneumatic soft robots are typically fabricated by molding, a manual fabrication process that requires skilled labor. Additive manufacturing has the potential to break this limitation and speed up the fabrication process but struggles with consistently producing high-quality prints. We propose a low-cost approach to improve the print quality of desktop fused deposition modeling by adding a webcam to the printer to monitor the printing process and detect and correct defects such as holes or gaps. We demonstrate that our approach improves the air-tightness of printed pneumatic actuators while reducing the need for fine-tuning printing parameters. Our approach presents a new option for robustly fabricating airtight, soft robotic actuators.
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- Award ID(s):
- 2237506
- PAR ID:
- 10532014
- Publisher / Repository:
- IEEE
- Date Published:
- ISBN:
- 979-8-3503-8181-8
- Page Range / eLocation ID:
- 249 to 254
- Format(s):
- Medium: X
- Location:
- San Diego, CA, USA
- Sponsoring Org:
- National Science Foundation
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