Design of a Rolling Capsule-Type Miniature Robot (RCMR) for Duct Inspection

Abstract

This study presents the design, static analysis, and manufacturing of a Rolling Capsule-type Miniature Robot (RCMR) for inspecting pipelines with inner diameters as small as 30 mm. The research addresses the challenges of miniaturization in robotics by developing a compact and efficient solution for traversing small ducts. The design process is carried out using Fusion 360, followed by a feasibility check through static analysis in FEASTSMT. The RCMR is constructed from a modular set of components held together by a combination of screws and various lock mechanisms, with an average device dimension of approximately mm2. Additive manufacturing, specifically 3D printing, is employed for fabricating the prototypes, offering design freedom and the ability to produce fully functional rigid miniature components with high accuracy and speed. The effectiveness of the RCMR is demonstrated through experimental results, showcasing its capability to traverse ducts with varying dimensions. This research lays the foundation for further advancements in miniature robotics for duct inspection, with potential future work focusing on wireless control systems, vertical movement capabilities, and the integration of advanced sensing technologies. © 2026 selection and editorial matter, Debanik Roy and Snehashish Chakraverty.