An important part of any new observatory construction project is to address the needs of long-term operations. The Giant Magellan Telescope Project, currently in the design phase, addresses these needs in several ways. We have hired an operations expert and have several other staff experienced in various aspects of observatory operations. Our high-level documents include an Observatory Operations Concept, describing how the observatory and its subsystems will work together to provide a high-level of service and performance to the astronomers that form their user base. It is also important to estimate the resources required for operations, and to develop a plan for the transition from project to operations.
Developing system behaviors early in the design process is an important tool to acquire more knowledge about interfaces and uncover requirements. The GMT design has progressed far enough that we are mostly writing more evolved behaviors, using the knowledge of existing requirements and interfaces, and describing in more detail the behaviors. Nevertheless, we are uncovering new requirements, and informing preliminary hazard analysis as we describe various operational tasks. Over 300 behaviors were identified by the subsystem teams in collaboration with the Systems Engineering team.
The Observatory Operations Concept outlines a set of “critical” behaviors, which those which require high reliability, the most resources, or are otherwise notable. These include exchanges of the cells holding the primary mirror segments, mirror recoating, installation and maintenance of instruments, cleaning the major optics, and recovering from major seismic events.
We are taking a similar approach to that used by software and controls, where we identify the “high level user stories” to inform the development regarding states, status, actors, actions and events.
Software and controls is taking a similar approach, using high-level “user stories” to inform their software interfaces.
This contribution will describe in more detail the goals of the Observatory Operations Concept and system behaviors. It will describe the tools and products of system behaviors. It will provide some examples of how system behaviors studies have led to significant requirements robustness and better informed design decisions.