|
The Low Frequency Array (LOFAR) is Europe’s largest radio telescope, originally designed, built and operated by ASTRON. It consists of an interferometric array of low band and high band antennas, distributed among 52 stations. Since 2018, a considerable upgrade of the main infrastructure has taken place both on the hardware and on the software side, the so-called LOFAR 2.0. The monitor and control software system of each LOFAR 2.0 station is based on the open-source TANGO-Controls framework, which manages the device architecture and the various functionalities of the station, including its states and transitions. Since each hardware device of the station is implemented as a software module, the startup of the station and its states transitions until a full operative state implies a non-trivial interaction and communication among the different device classes. The proposed design solution places each one of these devices in a specific hierarchical structure, which defines the parent-child relations and the allowed operations for its nodes. Besides that, the device hierarchy can be different according to the two main sequences that are involved in the station states transition: the power sequence and the control sequence. The whole set of sequential operations are entirely managed by the TANGO framework, in particular from a root device called Station Manager, which controls the children devices and the hierarchical sequences. In order to adhere to the TANGO architecture, the operations are mainly developed exploiting device attributes and properties, such that a potentially complex process is handled in a very straightforward, lightweight and maintainable way. The aforementioned software architecture has been already deployed and successfully tested on the LOFAR2 Test Station (L2TS) located in the Netherlands. Therefore, it is proving to be a primary feature for the whole LOFAR2 infrastructure, in view of a forthcoming fully operational phase within the next few years.
|
