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Mobile millimeter and centimeter scale robots often use smart composite manufacturing (SCM) for the construction of body components and mechanisms. The fabrication of SCM mechanisms requires laser machining and laminating flexible, adhesive, and structural materials into small-scale hinges, transmissions, and, ultimately, wings or legs. However, a fundamental limitation of SCM components is the plastic deformation and failure of flexures. In this work, we demonstrate that encasing SCM components in a soft silicone mold dramatically improves the durability of SCM flexure hinges and provides robustness to SCM components. We demonstrate this advance in the design of a flapping-wing robot that uses an underactuated compliant transmission fabricated with an inner SCM skeleton and exterior silicone mold. The transmission design is optimized to achieve desired wingstroke requirements and to allow for independent motion of each wing. We validate these design choices in bench-top tests, measuring transmission compliance, kinematics, and fatigue. We integrate the transmission with laminate wings and two types of actuation, demonstrating elastic energy exchange and limited lift-off capabilities. Lastly, we tested collision mitigation through flapping-wing experiments that obstructed the motion of a wing. These experiments demonstrate that an underactuated compliant transmission can provide resilience and robustness to flapping-wing robots.
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Squishy Volumes: Evaluation of Silicone as Camera-less Pressure-Based Input for 3-Dimensional Interaction
Low cost sensors and materials are increasingly of interest to de- signers for developing new ways to gather 3-Dimensional input. Silicone is a low cost material with capabilities of a variety of forms and sizes, thereby facilitating flexible construction. Given these properties, users can construct unique input solutions for a variety of applications. However, aside from other existing methods of measuring volume deformation, molded silicone (without added components inside the silicone and without added external cameras) for volumetric input has not been largely explored. In this paper we present an evaluation that investigated the parameters of silicone as volumetric input. The silicone volume has no added components inside making it easy to construct and use, however some external but small, flexible, and portable low-cost components are used for deformation measurement. We present the 3-dimensional input re- sults as a function of the physical pressure on the silicone by the volume of silicone. Researchers can use these input metrics to design a silicone-based device with desired size and thickness to achieve the desired sensitivity and resolution of input for their application.
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- Award ID(s):
- 1852579
- PAR ID:
- 10163533
- Date Published:
- Journal Name:
- In 2020 IEEE Conference on Virtual Reality and 3D User Interfaces
- Page Range / eLocation ID:
- 29 to 34
- 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/10.1109/VRW50115.2020.00013
