Delta Tau UK's Geo Brick LV

One of the most common requirements for our projects, whether it is for an astronomical or a high-energy physics application, is software for motion control. Optical telescopes have demanding requirements for precise and synchronised motion control of the telescope mount, whilst most high-energy physics facilities incorporate large numbers of motion axes that are used to position and move experimental equipment.

Motion control applications Software engineers from Observatory Sciences have been involved in motion control applications for many years with a lot of our experience gained with the Delta-Tau PMAC (Programmable Multi Axis Controller). Back in the 1990s, PMAC controllers were adopted by the Gemini telescope project to control the elevation and azimuth axes of the twin 8m telescopes.

OSL consultant Andy Foster worked to integrate them with the EPICS software framework that was used throughout the Gemini control system. Andy's work including enhancing the EPICS driver software to support Fast Data Logging on the PMAC itself, at the 2kHz servo rate. This proved extremely useful in commissioning where the data was fed into Matlab for 'on-the-spot ' analysis of problems and help with servo tuning.

The Gemini systems used a VMEbus interface for their PMAC systems, with software running under the Wind River vxWorks real-time operating system. More recently, large experimental control systems have begun to use the Linux operating system and the Australian Synchrotron Project has adopted EPICS with Linux as their software platform. German beamline supplier Accel has supplied several beamlines to the Australian Synchrotron and Observatory Sciences worked with them to produce a Linux driver for the Delta Tau PMAC2 Ultralite motion controller card. This driver is Continued available as open-source software and can be downloaded from the OSL website. At the Diamond Light Source in the UK, 800 motion axes will be
installed using Delta Tau controllers to control components in the second phase of synchrotron beamlines. These complement 700 already installed in Phase I. OSL has worked with Delta Tau PMAC systems throughout the Diamond control system, with beamline commissioning and enhancement work being performed by OSL consultants based at DLS.

OSL also worked with the UK companies Delta Tau and Micromech in the successful bid to supply Diamond with Delta Tau's next generation of PMAC motion controller.

The Delta Tau GeoBrick LV was designed especially for Diamond and can control up to 8 axes of mixed servo and stepping motor types. The latest development of this system has seen OSL produce EPICS software embedded in the GeoBrick LV-PC, to enable plug-and-play EPICS software integration.

For further information, contact: Andy Joslin,
Delta Tau UK Limited,
Holland Cottage, Kirby Road,
Great Holland, Essex
CO13 0HZ

Telephone: 01255 670196
Fax: 01255 850768
e-mail: ajoslin@deltatau.com