An Origami-Based Soft Robotic Actuator for Upper Gastrointestinal Endoscopic Applications

Area of Science:

• Soft robotics
• Biomedical engineering
• Materials science

Background:

• Existing soft pneumatic actuators face challenges in fabricating complex geometries for endoscopic use.
• Integrating cameras or tool channels often increases actuator diameter and complexity.
• Strain-limiting methods increase fabrication complexity, hindering translation into functional endoscopes.

Purpose of the Study:

• To present a novel multi-channel, single-material elastomeric actuator with a corrugated origami design for endoscopic applications.
• To overcome limitations of existing soft actuators, including radial expansion and fabrication complexity.
• To enable integration of endoscopic cameras within a compact actuator.

Main Methods:

• Fabrication of a multi-channel monolithic structure with an 8.5 mm diameter using a single elastomeric material.
• Incorporation of a corrugated (origami) design to limit radial expansion and improve bending efficiency.
• Evaluation of two actuator variants (30 mm and 40 mm length) under varying volumetric feed rates and pressures.

Main Results:

• Achieved a maximum bending angle of 150° with controlled volumetric and pressure inputs.
• Demonstrated a maximum bending angle of 200° when integrated with a manually driven endoscope.
• The origami design promotes low-pressure bending by opening corrugations while maintaining a small diameter and central lumen.

Conclusions:

• The developed origami soft pneumatic actuator offers a scalable, single-material solution for endoscopic applications.
• The design facilitates camera integration and provides efficient, low-pressure bending.
• This innovation simplifies fabrication and enhances the functionality of soft robotic endoscopes.