Defining Specifications

You can expose 3D Design geometric features at the PLM level by declaring them as specification features. The Define Specification command aims at typing geometrical results to prepare the Change of Level of Development (LOD) of a design.

This task shows you how to:

Assign an AEC Type
Expose a Typed Feature

Before you begin:

Open a typed solid, with a body and Generative Shape Design features. The type conditions are defined below:

Only bodies and GSD features can be typed. Then they can be exposed at the PLM level as a distributed feature because typed features can only be defined by Distribution object types. Distribution consists in a simple Copy As Result With Link of the geometrical result in a new PLM entity.
Specification features cannot be typed since they already contain an AEC type.

The Change Level Of Development command is used to synchronize exposed features and products with their specifications. It converts a feature-based model to a product-based model. It refers to the continuous level of development process with a code number evolving with the maturity of the design from 100 to 500. Once fully converted, a model can be edited concurrently and further detailed.

Assign an AEC Type

You can assign an AEC type to bodies and GSD features which get colored. Thanks to this visualization, you can distinguish which entity has not been typed. Then you can define a specification from a feature so that it can be instantiated later as a product.

Typing a feature with an AEC type does not change the nature of the feature, for instance its representation in the tree remains the same.

From the Civil Engineering section of the action bar, click Define Specification .
The Define Specification dialog box opens.
The assignment results in a feature extension added on the typed feature in the tree and bearing the name of the targeted AEC type. A publication is also created either at the 3D Part level or at the 3D Shape level. Thanks to this publication, a typed-feature can be recognized by the Change Level of Development command and then exposed at the PLM Level.
The typed-feature is also extended with business extensions (IFC/OmniClass/UniFormat for example) as described by the BIM Manager for LOD 100. For more information, see Building and Civil Assemblies User's Guide: Using the BIM Manager Editor.
In addition to the feature extension and the publication, a Base Axis System is created and aggregated under the typed feature in the tree. This axis system is used when changing the level of development to set a connection between the feature and the PLM object. It is located at creation on the feature geometry, as close as possible to the gravity center. After creation, the axis position is not updated when the feature geometry is changed.
Note: When aggregated under a GSD feature, the axis system cannot be deleted alone. When aggregated under a body, it can be deleted. In this case, the typed feature cannot be exposed. To restore the axis system, use the Define Specification command again.

Search for a type (Foundation for example) in the Define Specification dialog box.

Nothing can be selected if you do not have chosen a type.

Tips:

A list of the most recently used types (maximum 8) is available.
You can filter the elements of the tree by typing some wildcard characters in the top field. Use "*", for example: "Other*spatial" displays only types containing the substring "Other" followed by the substring "spatial".
The tree can also be filtered on intermediate nodes. Start the filtering by the ":" character. For instance “:Building*Spatial” displays all the types of the categories "Building & Civil Spatial Structure" and "Building Spatial Structure".
You can also search for an Object Type to assign more information at the feature's level.

Optional: Once a type is chosen, select an Object Type to define the feature, using Search , and extend the feature with the appropriate IFC/OmniClass/UniFormat extensions.
Optional: To display a preview of the selected object type in a side panel, click Template Helper .
A template viewer opens next to the Define Specification dialog box and displays the shape of the object type and axis systems.

In the Helper, you can move and zoom in the object type. Click again the same input and the object type moves back to its initial position.
To close the Helper, click or Close or
Select bodies or GSD features in 3D area or in the tree.
The feature is typed. In the 3D area, it is represented by a flag that displays the color, the type of geometry, and the name of the typed feature. There is one color per type (for example: 2 Piers have the same color).
Hover over the flag,
- To see the name of the chosen type.
- To un-type and remove the feature, click.
Optional: Add IFC attributes in the BIM Attributes panel. It is only possible when the feature has been typed. For more information, see Building and Civil Assemblies User's Guide: Adding and Editing BIM Attributes.
To end the command and validate your modifications, click OK.
You can also discard the changes by clicking Cancel or , or pressing Esc.

Expose a Typed Feature

You can expose a typed feature at PLM level using the Change Level of Development command.

Change Level of Development changes the level of development to account for increasing levels of details and complexity as the project evolves.

From the Component section of the action bar, click Change Level of Development .
The icon displayed in the Specification column is the one of the associated AEC type, not of the feature icon. The text displayed in the Exposed feature column is always equivalent to the text displayed in Specification column since the typed feature is both the specification and its feature result.

To expose the typed feature at the PLM level, click Process.

The feature is exposed. During the PLM exposition, a new 3D Part is created and instantiated. A Base Axis System is created in the 3D Shape, at the origin. This axis is published by a publication. A coincident constraint is placed between the created instance and the related typed feature. Therefore, the 3D Part origin is close to the design, allowing a design in multiple design ranges (for example, a large range for the representation containing the typed feature, and a normal range for the exposed products).

At the end of the exposition, if an IFC quantity volume attribute is available, then it is filled in with the volume measure of the typed feature in the BIM Attributes panel. For more information, see Building and Civil Assemblies User's Guide: Adding and Editing BIM Attributes.

Important: If the engineering connection is deleted, then there is no more implementation link between the instantiated product and its typed feature. The Change Level of Development command will consider the typed feature as Not Exposed and will propose to expose it again.

To filter the list of objects by status, click Filter

and choose from the status options.

Status Option	Description
Exposed	The object is exposed at the PLM level. The specification is exposed, and its implementing object is up-to-date.
Exposable	No implementing object and the specification is fully defined. You can expose the specification at the requested level (feature or product).
Not Exposed	Some inputs or parameters, or both are missing in the specification. You cannot expose it.