Modeling loops and connections

[ektrah]

A few questions about loops:

• What exactly is a loop?
  • brick:Loop is currently defined as a collection of connected equipment. (Would that be a s223:System in 223?)
  • Project Haystack defines it as pipework.
• How would I use brick:Loop in conjunction with 223:Connection?
  • Can the connections be inferred given a list of connected equipment?
• How can I indicate that a loop is a primary loop, secondary loop, tertiary loop?
  • See plantLoop and primaryLoop, secondaryLoop, tertiaryLoop in Project Haystack.

[gtfierro]

You think think of a Loop as the "closure" of the brick:feeds and/or the family of s223:connect... relationships. It was introduced in Brick in order to get around having to model individual pipes/flows/ducts/etc. The idea is that one could write a SPARQL query or SHACL rule that would infer membership in a Loop object.

I think s223:System could be used as a parent of brick:Loop but I haven't had this discussion with the 223 team yet. I would think that s223:Connection and s223:Connectable would be members of the brick:Loop.

We will need to decide if we want create an entity property which captures the "flavor" of the loop, or make the different kinds of loop their own class

[jahrling]

But a "closure" object is not what the description for Loop states: "A collection of connected equipment; part of a System". I would add a Hot_Water_Loop tag to each object that is a member of the hot water loop, not the terminal/closing object... or maybe I'm misreading.

Regarding parents, brick:System are types of systems, many of which typically have loops. s223:System could be harmonized with that. However, Loop is not a system type but rather a connected set of any type with specific, ordinal members. Therefore, 'Collection' feels like the correct parent.

Agreed on having a new class of primary, secondary, tertiary loop under Loop. These don't lend themselves to a triple or point to another object.