Enhancing Connection Strength in Freeform Modular Reconfigurable Robots Through Holey Sphere and Gripper Mechanisms

Abstract

Freeform modular self-reconfigurable robot (MSRR) systems overcome traditional docking limitations, enabling rapid and continuous connections between modules in any direction. Recent advancements in freeform MSRR technology have significantly enhanced connectivity and mobility. However, limitations in connector strength and operational efficiency in existing designs restrict performance. This paper proposes a rigid freeform connector and a rigid magnetic track design to improve the connection and motion performance of the SnailBot. Each SnailBot is equipped with a multi-channel rope-driven gripper, a metal spherical shell with densely distributed circular holes on the back, and a rigid chain design conforming to the spherical surface. This combination allows each SnailBot to move precisely along the surface of a peer, facilitated by the ferromagnetic spherical shell and magnetic track. The integration of the gripper and spherical shell hole array provides robust inter-module connections in any position and orientation. The effectiveness of these designs has been validated through a series of experiments and analyses, demonstrating improved connection and motion performance in the SnailBot dual-mode connector system and expanding its potential applications and functional capabilities.