Robotic Origami-Based Soft Endoscope (ROSE) for Minimally-Invasive Colonoscopy

Colonoscopy is crucial for early screening and treatment of colorectal lesions. Conventional colonoscopes are “back-wheel” actuated and semirigid devices, often resulting in time-consuming and invasive procedures for patients. In this article, the authors present the design, development, and preliminary validation of a “front-wheel” robotic origami-based soft endoscope (ROSE) for colonoscopy. ROSE (outer diameter: 26 mm; length: 100 mm) comprises two dumbbell-shaped anchoring actuators (AAs) connected at the ends of an origami-based central actuator (CA). Combining the radially-constrained origami structure of the CA (elongation of ∼43 mm at 25 kPa without external boundaries; expansion ratio > 350%) with AAs operating with an inflation and suction mechanism (inflation of chambers at 14 kPa and suction at −80 kPa), ROSE achieved a clinically-relevant target force ≥ 6 N with AAs’ low radial lumen expansion of ∼3 mm (∼18 N and ∼11 N for anchoring and pushing forces, respectively). Bending, aided by a cable-driven mechanism, achieves a maximum angle of ∼150° with 25 kPa. ROSE was preliminarily validated in three-dimensional in-vitro simulators and ex-vivo porcine colon, showing efficient navigation with an average speed of ∼2.4 mm/s and ∼1.5 mm/s, respectively.