Design, Control and Evaluation of a Novel Soft Everting Robot for Colonoscopy
Jialei Shi, Korn Borvorntanajanya, Kaiwen Chen, Enrico Franco, Ferdinando Rodriguez y Baena
AI summary
Problem
Traditional colonoscopies cause significant patient discomfort and perforation risks due to rigid tube insertion, while existing soft robotic alternatives lack adequate steering, autonomy, or clinical practicality.
Approach
The authors designed a pneumatic soft everting robot that unfolds a compliant fabric tube up to 1.6 m, equipped with an elastomer-based tip manipulator for omni-directional steering and a control system for teleoperation or camera-guided autonomous navigation.
Key results
- Fabricated a 1.6 m compliant tube with 18 mm diameter and >180° omni-directional tip steering
- Achieved phantom locomotion with average contact forces below 0.3 N
- Validated joystick teleoperation and autonomous image-guided navigation control pipelines
- Characterized maximum growth speeds up to 308.9 mm/s and steering angles up to 201.8° under pneumatic actuation
Why it matters
Provides a safer, more comfortable, and potentially autonomous colonoscopy platform for patients and clinicians, advancing the clinical translation of soft growing robots.
Abstract
Colonoscopy is a medical procedure used to examine the inside of the colon for abnormalities, such as polyps or cancer. Traditionally, this is done by manually inserting a long, flexible tube called a colonoscope into the colon. However, this method can cause pain, discomfort, and even the risk of perforation. To address these shortcomings, advancements in technology are needed to develop safer, more intelligent colonoscopes. This article presents the design, control, and evaluation of a self-growing soft robotic colonoscope, leveraging the evertion principle. The device features a tube with an 18 mm diameter, constructed from stretchable fabric, which grows 1.6 m at the tip under pressurization. A pneumatically driven, elastomer-based manipulator enables omni- directional steering over 180° at the tip. An airtight base houses mo- tors and spools that control the material and regulate growth speed. The robot operates in two modes: teleoperation via joysticks and autonomous navigation using sensor inputs, such as a tip-mounted camera. Thorough in-vitro experiments are conducted to assess the system’s functionality and performance. Results illustrate that the robot can achieve locomotion in confined spaces such as a colon phantom, while exerting contact forces averaging less than 0.3 N. Our soft robot shows potential for improving the safety and autonomy of colonoscopies, while reducing discomfort to patients.