3.5. Controls Hierarchy

An example of the control hierarchy addressed by the SWC software modeling process is shown in the Figure below. At the top level, the Sequencer subsystem orchestrates the operational workflow of high-level processes, such as telescope pointing and acquisition. At intermediate levels, control and operational logic dictate how to carry out the commanded operations. At the lowest levels, control demands are sent to devices that produce telescope axis motion. The purpose of the SWC software modeling process is to enable physical control that accurately captures the operating principles of the observatory.

Fig. 3.6 Conceptual Control Hierarchy

The GMT Instruments Controls Subsystem follows the same architectural design as other device control subsystems. Typically an Instrument Software and Controls Subsystem will include most of the packages described for control and will be developed following the standards and guidelines described in the SWCS Handbook. The operation of ICS, TCS and AO subsystems will be coordinated by the GMT Sequencer in order execute automated observation or calibration operations. The ICS data pipeline packages are integrated in the GMT Data Processing System so quick look and data products management is operated in a uniform way across the observatory. Analogously instrument specific user interface panels and observing tools are integrated in the Observatory Operations System to ensure consistent and seamless implementation of observatory workflows.