Integrating Supervision, Control and data Acquisition - The ITER Neutral Beam Test Facility experience

The ITER Neutral Beam (NBI) Test Facility, under construction in Padova, Italy, is developing the ITER full scale ion source form the ITER heating neutral beam injector, referred to as SPIDER, and the full size prototype injector, referred to as MITICA. The Control and Data Acquisition (CODAC) system for SPIDER has been developed and is going to be in operation in 2015. The system is composed of four main components: Supervision, Slow Control, Fast Control and Data Acquisition. These components interact each other to carry out the system operation and, since they represent a common pattern in fusion experiments, software frameworks are available for each (set of) component. Using a framework to carry out specific functionality offers several advantages when compared to specific development, among which the possibility of reusing software solutions and sharing proved solutions among different experiments. Several frameworks have been adopted in the fusion community, among which EPICS for supervision, MDSplus for data Acquisition and PCS, DCS and MARTe for real-time control. To date, ITER has decided to adopt EPICS for supervision and slow control, and a final decision has not been taken for the other components. In order to have the system ready for operation in 2015, SPIDER CODAC will use solutions specific to the test facility for those components for which the corresponding concepts are not fully mature in the ITER design, in particular MDSplus for data acquisition and MARTe for real-time control. This solution proved adequate for SPIDER CODAS but may not be directly applicable to MITICA CODAS as that is going to be directly used by ITER, and therefore will be subject to the ITER directives. In order to reuse as far as possible the architecture developed for SPIDER, it is important to clearly define the boundaries and the interfaces among the system components so that the implementation of any component can be replaced without affecting the overall architecture. This work reports the experience gained in the development of SPIDER components, highlighting the importance in the definition of generic interfaces among component, showing how the specific solutions have been adapted to such interfaces and suggesting possible approaches for the development of other ITER subsystems.