How to Engineer a Complete Control System for a Gamma Beam
How Cosylab designed and delivered a complete control system for the Gamma Beam System of the Extreme Light Infrastructure Nuclear Physics (ELI-NP) facility
ELI-NP in Magurele, Romania, is planned to become the most advanced, highly intense laser and gamma beam machine in the world. In 2014, a European Consortium, EuroGammaS, won the tender to build a Gamma-Ray Source for fundamental and advanced research at the ELI-NP facility. The Consortium started looking around for a subcontractor to deliver the complete control system for a custom Gamma Beam System (GBS)— and chose us.
Choosing open-source software for the control system
We were convinced that the control system should be based on industry-standard open-source software and structured in such a way that made it is easy to upgrade — substituting elements, devices or subsystems with new counterparts. We proposed the EPICS framework to be used for the ELI-NP GBS control system. EPICS is an open-source software infrastructure, optimised for building large distributed control systems to operate devices such as particle accelerators, large experiments and major telescopes.
Cosylab’s EPICS implementation for the ELI-NP GBS is based on a modular control system design that leverages solutions developed at other similar facilities. Even “out of the box” EPICS, with its set of strict processes and conventions, ensures that any custom and project-specific development can be performed in a standardised and coherent manner.
For the ELI-NP GBS project, Cosylab developed device integration for several types and classes of devices, such as, for example, a Fast Digitizer into EPICS for GBS Beam Charge Monitoring.
Off-the-shelf technology is rarely right for Big Physics
For Big-Physics facilities with unique systems requirements, such as the ELI-NP GBS, commercial off-the-shelf technology is rarely good enough. Instead, cutting-edge hardware with custom integration is the only way to go.
While any custom device integration has its challenges, an excellent example of a demanding device integration into EPICS for the project was an ADC to digitise the output of the integrating current transformer (ICT).
An ADC with a sufficiently high sampling rate was needed for accurate measurement — with a multi-GS/s sampling rate, a wide input-voltage signal-range of 0–10 V and compatibility with the CompactPCI platform.
Going the extra mile and proving the suitability of EPICS
We put all of our effort into defining the scope and the integration of the control system for the ELI-NP Gamma Beam System, and it paid off. We completed all of our contractual work on the software development for the GBS control system, performed a successful factory acceptance test and delivered all the software components to our customer, EuroGammaS, by the end of 2016.
Over the course of 2017, we also provided the hardware and equipment for ELI-NP as specified in our customer’s requirements. We are proud of our achievement, especially in the light of the tight project schedule, and that we could, again, prove the suitability of the EPICS framework for demanding applications.
Gašper Pajor, David Pahor, Cosylab
