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In nature, click-beetles use a unique hinge structure between their prothorax and mesothorax that acts as a latch-mediated spring actuation system to produce a high acceleration that can result in a jump. This mechanism enables them to jump a height of several times their body length without using their legs when the beetle is unconstrained. To study the beetle jump trajectory, we designed simplified beetle-inspired prototypes and a launching platform. The simplified prototypes are fundamentally two masses connected by a spring. The masses simulate the portion of a click beetle’s body located anteriorly (M1) and posteriorly (M2) to the clicking mechanism, and the spring simulates the elastic energy storage element. The launcher uses a quick-reaction release mechanism and magnetic actuator to simulate the unlatching process. In trajectory analysis, the parameters that are most important are initial velocity at take-off and the take-off angle since both the click beetles and the prototypes are governed by ballistic motion. We determined that morphological features such as elytra (body) curvature and the ratio of the two body masses affect these two dynamic parameters. Our findings provide further insight into the design and fabrication of legless jumping robotic mechanisms and apply engineering models and experimental tools to answer key biological questions.
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Design and Fabrication of Concentric Tube Robots: A Survey
Concentric tube robots (CTRs) have drawn significant research attention over the years, particularly due to their applications in minimally invasive surgery (MIS). Indeed, their small size, flexibility, and high dexterity enable several potential benefits for MIS. Research has led to an increasing number of discoveries and scientific breakthroughs in CTR design, fabrication, control, and applications. Numerous prototypes have emerged from different research groups, each with their own design and specifications. This survey paper provides an overview of the state-of-the-art of the mechatronics aspects of CTRs, including approaches for the design and fabrication of the tubes, actuation unit, and end effector. In addition to the various hardware and associated fabrication methods, we propose to the research community, a unifying way of classifying CTRs based on their actuation unit architecture, as well as a set of specification details for evaluation of future CTR prototypes. Finally, we also aim to highlight the current advancements, challenges, and perspectives of CTR design and fabrication.
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- PAR ID:
- 10402474
- Date Published:
- Journal Name:
- IEEE transactions on robotics
- ISSN:
- 1941-0468
- 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
- Journal Article:
- https://doi.org/10.1109/TRO.2023.3255512
