Air Bearing Performance Without Air Bearings
Tue, 08/12/2008 - 8:14am
Steinmeyer's new PMT 160 series stages to acheive straightness and flatness runout of 50 nanometers or less. This decoupling arrangement is accomplished using mechanical cross roller bearings instead of large and expensive air bearings. Disturbance forces can elastically deform base plate, bearing, and saddle and interfere in the straightness and flatness of the whole stage system. By applying flexure designs well known in piezo micropositioning stages, a solution has been developed that eliminates these effects. The PMT 160 offers travels from 50 mm to 300 mm, with standard positioning accuracy of less than 10 µm and repeatability of +/- 0.5 µm when driven by either dc servomotor (with rotary encoder) or dc stepper motor.