A mobile, spherical robot includes a spheroid shell, an internal assembly secured to the shell, and a head disposed atop the shell. The internal assembly is disposed within the shell for propelling the mobile robot. The internal assembly includes a base, a flywheel assembly rotatably secured to the base, a drive assembly rotatably secured to the spheroid shell and configured to propel the mobile robot by rotating the spheroid shell about the base a pivoting arm pivotably secured to the base, and the pivoting arm. The head is secured to the magnetized end of the pivoting arm through the spheroid shell. The head is configured to move relative to the spheroid shell and relative to the base by the pivoting of the pivoting arm.