ATLAS: A NOVEL KINEMATIC ARCHITECTURE FOR SIX DOF MOTION PLATFORMS

Abstract

Conventional training simulators commonly use the hexapod configuration to provide motion cues. While widely used, studies have shown that hexapods are incapable of producing the range of motion required to achieve high fidelity simulation required in many applications. This paper presents an overview of the Atlas platform: a novel six DOF motion platform architecture. Orienting is decoupled from positioning, and unlimited rotations are possible about every axis of the mechanism. The decoupling is accomplished by fixing a three DOF spherical orienting device, called the Atlas sphere, on a gantry with three linear axes. The key to the design is three omni-directional wheels in an equilateral arrangement, which impart angular motions to a sphere, thereby providing rotational actuation. The omni-wheels and their castor rollers provide virtually friction-free motion parallel to each omni-wheel rotation axis creating the possibility for unconstrained rotational motion. Since the Atlas sphere rests on these omni-wheels, there are no joints or levers constraining its motion, allowing full 360° motion about all axes. The motivation, architecture, and potential applications for this motion platform are described.