Aerotech's new ALAR large aperture rotary stages combine brushless direct-drive motor technology and integral precision encoders with angular contact bearings for backlash-free, fast and ultra precise positioning with a high payload capacity. Vacuum versions up to 10-6 are available.
Featuring compact space saving housings with aperture sizes of 100mm, 150mm, 200mm, 250mm and 325mm, the range is aimed at high throughput single and multi-axis testing and alignment applications across manufacturing and research where the process calls for payloads that must be at the centre of rotation such as photonic component alignment or where it is desirable to work through the aperture.
Accuracy through the range is 3.9 arc sec (calibrated) and repeatability is 0.3 arc sec. Resolution is dependant upon a wide choice of encoders and multiplier options with the fundamental stage resolution before encoder multiplication between 4.3 arc sec and 10.3 arc sec. With Aerotech controls, the resolution is increased between 1000x to 8000x making the useable stage resolution as low as 0.00054 arc sec. Equally impressive specifications include wobble at 2.0 arc sec.
The range is available in continuously rotating or limited travel versions and each aperture size is offered in two height configurations. The standard height profile unit (SP) is designed for the highest payload and moment load stiffness for offset and cantilevered loading. The low profile unit (LP) has a height reduction of around 60 percent for even better space saving in installations where the load is centralised and its axis of rotation is parallel to gravity. The stage height is between 65mm (for the 100mm aperture low height version) and 160mm (for 325mm aperture standard height unit). The resulting load characteristics for the range are impressive with axial loads between 1500N to 5840N and maximum moment loads from 267Nm to 2670Nm. The stage has integral connectors for simplified and uncomplicated installation and throughout the range compactness in design has been of key importance; the maximum wall thickness measured from the exceptionally large aperture to the outer housing is between 75mm to 100mm.
With zero backlash, excellent accuracy and repeatability, low wobble and bearing run out, extremely smooth motion and exceptional positioning stability, the ALAR range is a much superior alternative to traditional large aperture worm-wheel based stages with over five times the speed capability, greatly improved reliability and a considerably extended life. With a faster, increased accuracy system customers are able to produce improved products at higher throughput rates making the total cost of ownership significantly lower over the extended life of their manufacturing system.
