PLM Implementation

Revision-Controlled Workspaces

Revision-controlled workspaces enforce a special level of control on Workspace Items. Modifications to these items are done only during specific windows and each set of modifications is captured in a snapshot of the item record called a revision. Each revision represents a phase in the development of that item. Once a new revision is created, the previous revision of the item, and hence all previous revisions, are permanently locked and can not be changed in any way( with the exception of uncontrolled item details sections – discussed below).

Lifecycle Phases

As the process of revising items in a revision-controlled workspace takes place, the items pass through phases of a product lifecycle. Theses phases and the transitions between them can be tailored by your Administrator, but in most cases these phases are:

• Unreleased – Generally, newly created records in a revision-controlled workspace are unreleased. They can be modified by anyone with edit rights to the workspace. Unreleased items typically represent a specification/definition of an item or product.
• In Design – In Design items are typically those undergoing development. Design iterations create numerical revision numbers for each item.
• In Production – These are items that have been released into production.
• Obsolete – Obsolete items are those that have reached their end of life and are no longer being produced.

Revisioning Workspaces and Change Windows

The process of revising items and moving them through the product lifecycle is accomplished by a Revisioning Workspace. Revisioning workspaces operate in conjunction with Revision-Controlled Workspaces to implement a product lifecycle management system.

Typically the Revisioning Workspace encapsulates the documentation related to revising/releasing one or more items in a Revision-Controlled Workspaces.

The items in the Revision-Controlled Workspaces are associated with the Revisioning Workspace item through the Linked Items tab (see Linked Items). When revision-controlled items are added in this way, an open change window is created for these items. A green stamp appears in the Item Header of each revision-controlled item to indicate it is now editable.

The Revisioning Workspace has workflow defined with a specific state called the “Change Management State” or “CM State”. Once this state is reached, the linked items are transitioned to the next phase of the lifecycle defined for each item, and the change window is closed. Optionally, the change window is closed earlier if a Lock State is specified that comes before the CM State is reached.

Revisions, Working Versions, Superseded Items, and Bills of Material (BOMs)

Changes to items in a Revision-Controlled Workspace can occur only when an item is Unreleased or when a change window is opened via the Revisioning Workspace. In either case, any changes are applied to what is called the "Working Version."

Unreleased items are such that the working version is the latest and only version. These items appear with an asterisk in the item selection list. When referenced in a bill of material these items are shown with a lower case w as the revision number to indicate this is an unreleased working version. When an unreleased item is released via the CM workspace the working version becomes hidden until the next change window.

The working version of a released item once again becomes available for modifications upon creation of a new change window.

When a released item is revised via the CM workspace the previous release becomes superseded and all references to this superseded item in all the bills of material are updated to point to the new revision once the CM State is reached.