In this article, the mechanical design and the practical im plementation of a high-performance, three-degree-of-freedom, camera-orienting device is addressed. The agile eye, as it is referred to, is based on a spherical 3-DOF parallel mechanism, which leads to high-performance dynamics. The kinematics of such a mechanism is briefly recalled, and its mechanical prop erties are described. Then, experimental results obtained with the prototype are presented and commented upon. Because of its low-moving inertia and its inherent stiffness, the mechanism is capable of velocities larger than 1,000°ls and of accelera tions larger than 20,000°/s2.
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