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In clinical practice, therapeutic and diagnostic endoluminal procedures of the human body often use a scope, catheter, or passive pill-shaped camera. Unfortunately, such devices used in the circulatory system and gastrointestinal tract are often uncomfortable, invasive, and require the patient to be sedated. With current technology, regions of the body are often inaccessible to the clinician. Herein, a magnetically actuated soft endoluminal inchworm robot that may extend clinicians’ ability to reach further into the human body and practice new procedures is described, modeled, and analyzed. A detailed locomotion model is pro- posed that takes into account the elastic deformation of the robot and its interactions with the environment. The model is validated with in vitro and ex vivo (pig intestine) physical experiments and is shown to capture the robot’s gait characteristics through a lumen. Utilizing dimensional analysis, the effects of the mechanical properties and design variables on the robot’s motion are investigated further to advance the understanding of this endoluminal robot concept.
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Design and Fabrication of a Deployable Tensegrity Millirobot for Next-Generation Gastrointestinal Diagnostics and Treatment
Abstract The advent of robotics in medicine has brought about a paradigm shift, enabling minimally invasive interventions for in-vivo practices. Pill-based robots, specifically designed at the millimeter scale, have emerged as a viable alternative to traditional endoscopic methods for gastrointestinal tract diagnostics and treatment. These millirobots, capable of navigating the complex and constrained environments of the human body, offer a significant advantage by enabling thorough visualization or targeted drug delivery in a single session without the need for sedation. We previously developed a novel deployable tensegrity robot, designed for gastrointestinal diagnostics and treatment, which addresses the limitations of conventional capsule endoscopes through its unique structure and locomotion mechanism. Tensegrity structures, characterized by a network of components in tension and compression, provide an innovative solution to the challenges of designing robots for in-vivo applications. Our millimeter-scale tensegrity robot leverages the inherent advantages of such structures — lightweight, high stiffness, and adaptability — to navigate through densely packed tissues and high-pressure environments within the GI tract. Inspired by the locomotion of earthworms, the movement mechanism of the robot enables efficient navigation and precise positioning, significantly reducing the risk of retention and ensuring patient safety. This paper investigates the design and fabrication process of the tensegrity robot, focusing on achieving a high folding ratio to facilitate its deployment as a pill-based robot. Through a comparison of the robot’s fabricated dimensions with the theoretical design, we evaluate the accuracy of the fabrication process, highlighting the potential of this innovative approach in transforming GI tract diagnostics and treatment. The deployment of such tensegrity-based millirobots marks a new era in medical devices, promising enhanced patient safety and comfort through non-invasive methods.
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- PAR ID:
- 10556595
- Publisher / Repository:
- American Society of Mechanical Engineers
- Date Published:
- ISBN:
- 978-0-7918-8841-4
- Format(s):
- Medium: X
- Location:
- Washington, DC, USA
- 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/DETC2024-142947
