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Endoluminal devices are indispensable in medical procedures in the natural lumina of the body, such as the circulatory system and gastrointestinal tract. In current clinical practice, there is a need for increased control and capabilities of endoluminal devices with less discomfort and risk to the patient. This paper describes the detailed modeling and experimental validation of a magneto-electroactive endoluminal soft (MEESo) robot concept that combines magnetic and electroactive polymer (EAP) actuation to improve the utility of the device. The proposed capsule-like device comprises two permanent magnets with alternating polarity connected by a soft, low-power ionic polymer-metal composite (IPMC) EAP body. A detailed model of the MEESo robot is developed to explore quantitatively the effects of dual magneto-electroactive actuation on the robot’s performance. It is shown that the robot’s gait is enhanced, during the magnetically-driven gait cycle, with IPMC body deformation. The concept is further validated by creating a physical prototype MEESo robot. Experimental results show that the robot’s performance increases up to 68% compared to no IPMC body actuation. These results strongly suggest that integrating EAP into the magnetically-driven system extends the efficacy for traversing tract environments.

In clinical practice, therapeutic and diagnostic endoluminal procedures of the human body often use a scope, catheter, or passive pill-shaped camera. Unfortunately, such procedures in the circulatory system and gastrointestinal tract are often uncomfortable, invasive, and require the patient to be sedated. With current methods, 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 proposed 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 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.