AML has developed a custom high-resolution rotation stage for a customer application requiring precise rotational positioning in ultra-high vacuum. 
The principal requirement was a full-step resolution of 0.001° across a complete 360° range. This was achieved through a combination of custom bevel gearing and a 50:1 planetary gearhead fitted to an AML D42.2 UHV stepper motor.

Vacuum: 1x10^-10 mbar
Travel: 0-360°
Full-step resolution: 0.001°
Bidirectional repeatability: better than resolution
Motor and gearhead: D42.2 with PG42-050
Positional feedback: absolute encoder
Design: Partially enclosed design 

The application also required that the stage feature an absolute encoder. To reduce the risk of the encoders digital light pulses interfering with other components inside the customer’s vacuum chamber, a partially enclosed design was requested. A small opening was incorporated into the casing to allow the encoder readhead cable to exit. The base was also widened and manufactured with customer-specified mounting holes to simplify installation within the system. 

The absolute encoder leadout terminates with AML’s VC9DF connector and VC9DB strain relief backshell. This UHV-compatible connector enables the encoder to be connected directly to an AML VF9D-40CF feedthrough. 
AML’s SMD4-E stepper motor drive is used to interface with the absolute encoder. For more information, view the SMD4 product page here: SMD4 Stepper Motor Drive - Arun Microelectronics

If you would like to discuss your in-vacuum motion requirements, or are interested in learning more about this custom rotation stage, please contact our team at sales@arunmicro.com.