PenduMorph: Development and Motion Analysis of Pendulum-Actuated Rolling Reconfigurable Spherical Robot with Magnetic-Coupling

2026-06-21

AI Summary

This work addresses the challenges of structural integrity, reliable reconfiguration, and stable rolling faced by modular robots in complex, contact-rich environments. To this end, the authors propose PenduMorph—a fully enclosed, spherical, reconfigurable rolling robot. The platform integrates a two-degree-of-freedom internal pendulum actuation mechanism, a magnetic coupling docking system, onboard control electronics, and wireless battery power, enabling both autonomous single-module rolling and coordinated multi-module locomotion. Notably, the design innovatively extends pendulum-based actuation to a fully sealed spherical architecture, ensuring hardware protection while simultaneously supporting independent mobility and robust inter-module connections. Experimental results demonstrate the system’s reliable operation and diverse reconfigurable rolling behaviors in both single- and dual-module configurations.

Abstract

This paper presents "PenduMorph", a wireless reconfigurable rolling spherical robot designed as a modular platform for enclosed locomotion and inter-module interaction in challenging environments. The proposed robot extends our previous pendulum-actuated rolling disk concept to a fully enclosed spherical architecture integrating a 2-DoF internal pendulum, onboard control, battery-powered operation, and magnetic docking. The design aims to combine independent rolling mobility with protected hardware and reliable reconfigurability. We first present the robot design and an analytical study of the magnetic coupling mechanism to evaluate retention and interaction between coupled modules. We then experimentally investigate key motion behaviors at both the single-module and dual-module levels, including independent rolling, magnetic coupling, and coordinated coupled motion. The results show that the proposed platform enables stable wireless operation and a set of distinctive reconfigurable rolling behaviors, providing a useful foundation for future modular spherical robots operating in contact-rich and demanding environments.

Problem

• reconfigurable spherical robot
• pendulum-actuated rolling
• magnetic coupling
• modular locomotion
• enclosed environment

Innovation

• reconfigurable spherical robot
• pendulum actuation
• magnetic coupling
• modular locomotion
• enclosed rolling platform