Creating requirements

The first step in requirements identification is to gather information for source requirements. Such information may be gathered from telephone conversations, meetings, regulatory agencies, standards organizations, and external documents.

The next step is to analyze that information, looking for issues, ideas, and keywords expressed by the customer. By those guidelines, irrelevant material can be separated and discarded. The remaining information becomes the content for the source requirements.

You can create and edit requirement content directly in the Systems Engineering perspective or author it in Microsoft Office Word. (If you use the stand-alone version of Word, rather than integrated Word, you must import the requirement content into Teamcenter.) The following example shows a very simplified requirements hierarchy.

000075/A;1 - Speed spec (ReqSpec)
Req001144/A;1 - Acceleration (Requirement)
Req001145/A;1 - Speed range (Requirement)

Requirements can be structured in a hierarchy in which the levels convey relationships among the requirements. Each individual requirement is identified by a unique number defined in the bl_hierarchical_number property for the requirement object.

Within a hierarchy, a requirement may occupy the highest level, as a sibling of all other requirements at level 1. Alternatively, a requirement may occupy a lower level, as a child of the requirement at the next higher level. In turn, a child requirement may also be a parent of children at even lower levels.

Although a traditional requirements specification can include hundreds or thousands of requirements, it is typically managed as a single document. In Teamcenter, however, each requirement is managed as a separate object, with specific properties and access control.

Also in the identification process, requirements may be organized by project according to their intended implementation. This organization partitions the requirements around designs, so that records can be generated for reference in comparing changes with previous structures.

Requirement content consists of familiar elements such as text paragraphs and lists, hyperlinks, tables, graphics, equations, and special characters.

Working with hierarchical requirements is similar to working with numbered paragraphs in Word's outline view. Each requirement has a paragraph number that corresponds to the requirement's level in the hierarchy. The current level and paragraph number can be changed by promoting or demoting the requirement or by manually changing the requirement's number property.