  This paper introduces a cube-based reconfigurable robot that utilizes an
electromagnet-based actuation framework to reconfigure in three dimensions via
pivoting. While a variety of actuation mechanisms for self-reconfigurable
robots have been explored, they often suffer from cost, complexity, assembly
and sizing requirements that prevent scaled production of such robots. To
address this challenge, we use an actuation mechanism based on electromagnets
embedded into the edges of each cube to interchangeably create identically or
oppositely polarized electromagnet pairs, resulting in repulsive or attractive
forces, respectively. By leveraging attraction for hinge formation, and
repulsion to drive pivoting maneuvers, we can reconfigure the robot by
voxelizing it and actuating its constituent modules - termed Electrovoxels -
via electromagnetically actuated pivoting. To demonstrate this, we develop
fully untethered, three-dimensional self-reconfigurable robots and demonstrate
2D and 3D self-reconfiguration using pivot and traversal maneuvers on an
air-table and in microgravity on a parabolic flight. This paper describes the
hardware design of our robots, its pivoting framework, our reconfiguration
planning software, and an evaluation of the dynamical and electrical
characteristics of our system to inform the design of scalable
self-reconfigurable robots.

Robotics