Tapered Circular Cross Section Driving Mechanisms and the Omnidirectional Base Equipped with Units

In this study, we propose and develop an improved model of the tapered circular cross-section mechanism, which exhibits high step-and gap-climbing capabilities by reducing the running resistance of its passive crawler. Using four of these improved mechanisms, we constructed an omnidirectional mobile base and evaluated its performance. We first describe the basic principle and the first prototype of the proposed mechanism, followed by step and gap traversal tests using a single unit. Next, based on observed issues, we designed and fabricated a second prototype with several improvements. Subsequently, we developed a four-unit omnidirectional mobile platform equipped with the mechanism, and conducted mobility experiments including omnidirectional movement, step climbing, and gap traversal. The results confirmed that the proposed mechanism functions effectively as a locomotion unit for omnidirectional mobility over uneven terrain.