A clear aperture improves product feed-through, laser-beam delivery, and cable clearance. Large air-bearing surfaces increase stiffness and load capacity, which improves axial, radial-error, and tilt-error motions. Reduced face-error motion boosts planar performance. The Series utilizes S-Series, slotless, brushless motors with advanced magnetic circuitry for high torque with minimal heat. The slotless design is zero cogging and torque-ripple-free. An optical encoder is standard. When coupled with the manufacturer's feedback multipliers and controls, resolutions of <0.03 arc-sec are possible.