Modeling and Analysis of a Soft Endoluminal Inchworm Robot Propelled by a Rotating Magnetic Dipole Field

Abstract

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 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 (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.