The invention is an instrument suitable for aeronautio and nautical staff training on ground, and for entertainment. It is composed of a base frame, three rings, hand/foot racks and shaft assemblies. The three rings are concentric whose three planes intersect perpendicularly each other within a coordinate system. Movable parts revolve round cordinate axes respectively while the three axes intersect at the center perpendicularly, so the result motions are only limited by one center and various motions, such as rotation, roll, equilibrium, location are implemented freely under the application of external forces.