spherical robot 3d model

3D printable model asset of a 40cm mechanical sphere robot, sci-fi military drone aesthetic. Outer layer is a 400mm dual-hemisphere thin matte-black carbon-fiber shell, split evenly at the equator. The shell features hidden shingle-style overlapping tiers at the upper and lower quadrants forming concentric ventilation gaps. Suspended exactly at the geometric center (0,0,0) is a rigid 150mm metallic reaction cube chassis. The vertical axis of the cube is a wide 74mm completely hollow open air-duct tube. The cube frame is supported by two nested, concentric skeletal carbon-fiber rings: an inner gimbal loop at 330mm diameter and an outer gimbal loop at 350mm diameter. Rings are connected together via small cylindrical pivot pins and miniature bearing caps aligned perfectly at 90-degree offsets along the vertical North-South axis and horizontal East-West axis. Flat high-RPM reaction wheel disks are mounted flat against the left and right interior walls of the cube flanking the central vert