Representations

Overview

Use the BMEXPLODE, BMEXPLODEMOVE, BMTRAILINGLINES, and VIEWBASE commands.

The exploded (created with BMEXPLODE command) and sequence (created with BMSEQUENCE command) representations functionality create associative representations of assemblies and do not modify the assembly itself. Representations are stored in dedicated blocks, which can be edited and inserted according to your needs. You can also generate drawing views from the representations.

Representations are associative. Each part in a representation is linked with the corresponding part in the assembly. Use the BMBALLOON command to update exploded representations to the current state of the assembly, as well as place balloon annotations on the corresponding drawing view(s).

Example of Exploded Representation

Levels of the exploded representation

Representations contain references to the components.

2 levels of Representations are supported: Top and Bottom.

  • Top level:

    The representation contains references to the top-level components only. Top-level components are components inserted directly into the main assembly. A top-level component in a representation is not exploded further - all its parts and subassemblies remain assembled. A top-level representation allows you to see the basic composition of your assembly.

  • Bottom level:

    The representation contains references to the bottom-level components only. Bottom-level components are terminal parts, which do not contain other parts or subassemblies. Bottom-level representations allow you to view all parts in isolation.

Note: If Bottom level is selected and there are some middle-level components containing not only inserts of components, but also other entities, these entities will be lost in the representation because it is not possible to reference them correctly. Those entities must be converted into corresponding bottom-level components first.

Algorithms

BricsCAD provides 3 algorithms to automatically create representations and a manual algorithm.

Algorithm Description
Table by Type Create a table-like explosion where components of the same type are grouped in rows.
Linear Find the disassembly sequence of components in a given direction and order the components.
Note: This considers possible physical collisions between components. The components can be moved by the algorithm only if there are no other components (not yet moved), that block them.
Automatic Find the disassembly sequence of components with respect to the assembly hierarchy.
Note: This considers all possible physical collisions. For each part or subassembly, the direction of movement is identified automatically.
Manual Create an exact copy of the assembly ready for custom edit. In this mode, you can create a custom representation without changing the main assembly.

Example: The main drive shaft assembly

Example: main drive shaft assembly

Table by Type Linear Automatic
Top level
Bottom level

Steps and animations

Representations may contain one or several steps, which describe a particular assembly or disassembly sequence. Each step corresponds to a set of components that must be moved at this particular stage in order to assemble or disassemble the main assembly. All representation algorithms automatically create all the required steps. You can also delete, merge, split, move, or add extra steps.

Each step has a unique name that can be used to describe the step.

It is possible to animate a particular step, as well as the entire sequence of steps, both in direct and reverse directions (to get disassembly and assembly animations). In order for the animation to work properly, an initial step that defines the initial state of the assembly must be present in the representation. Use the Auto hide property of the representation to automatically hide components that are not important for a particular step during the animation.

Edit representations

Each representation is stored as a block. This allows you to edit the representation with the block editor.

Important: Do not use the REFEDIT command to edit representations. This command is incompatible with exploded representation steps.

To open the representation for edit:

  1. Right-click the required representation in the Mechanical Browser.
  2. Select Edit from the context menu.

    The block editor will open automatically.

    Note: You can open the representation for edit by double-clicking it.
Tip: As an alternative, you can open the representation for edit at the end of the BMEXPLODE command.

When the representation is open for edit, you can change the state of a step to the current step by double-clicking it.

Note: If you change the current step, you will discard all unsaved modifications, as well as any operation on steps. Make sure that all modifications are saved before you change the current step or perform any other operation.

Use the DMMOVE, MOVE, DMROTATE, and BMEXPLODEMOVE commands to move components, inside the representations, to the required positions. The BMEXPLODEMOVE command automatically adds all necessary steps after the current step. For other operations, save the current step after the edit is complete. Only the difference between the current step and the previous one is stored.

It is also possible to change the representation by performing operations on steps.
Example: if you remove a step, all components moved at this step will be returned to their respective positions before that step.

It is also possible to associate text annotations (MTEXT command) and any entities other than assembly parts with a selected step. Those annotations and entities will be visible only at the selected steps and will be hidden when other steps are active; however, their positions are not stored in steps.

Save the current step (Save current state option) once you have finished the edit. If not, changes will be discarded.

Trailing lines

Trailing lines help explain the relationship between parts. It is a 3D polyline that represents a trajectory and displays the movement of a part during the disassembly process.

Example of trailing lines

Use the BMTRAILINGLINES command to add trailing lines to a representation that is open for edit. This tool creates all trailing lines. The information from the exploded view steps is used to do this.

You can generate trailing lines for all parts, for a subset of parts, or for each step. For a subset, trailing lines will be built for parts from that subset only, although only necessary trailing lines will be added. Some parts may not have trailing lines at all. You can also manually select 2 parts to add a trailing line between. A trailing line for a step will be shown only for this step.

When a trailing line is computed, the algorithm automatically determines the location of the part and the location from where the part was removed to compute the trajectory. It considers the movements of both parts.

Each trailing line is displayed in the Mechanical Browser panel. With the Mechanical Browser panel, you can see all trailing lines in the model; highlight, select and zoom to parts connected with the selected line; rename or remove the trailing line.

You can edit the trailing line(s) with the standard 3D polyline edit tools.

Exploded view trailing line properties

Create a representation

Use the BMEXPLODE command to create a representation of the current assembly.
Note: Local mechanical components based on blocks and solids, and mechanical external references are fully supported in exploded views.
  1. Choose one of the following actions to launch the BMEXPLODE command:

    • Click the Explode tool button on the Tools panel of the Assembly tab.

    • Click the Explode tool button on the Assembly toolbar.

    • Select Explode in the Assembly menu.

    • Type BMEXPLODE in the Command line.

    You are prompted: Select explosion algorithm [Table by types/Linear/Automatic/Manual/Update/Settings]:

  2. If applicable, set the Level and the set Name of the exploded representation using the Settings option.
  3. Select the algorithm.

    You are prompted: Select exploded view behavior [Edit/Generate drawing views/Finish]:

  4. Perform one of the following actions:
    • Select Edit to edit the exploded representation.
    • Select Generate drawing views to generate drawing views of the exploded representation.
    • Select Finish to finish the command.

Generate drawing views of the representation

  1. Launch the VIEWBASE command.

    You are prompted: Select objects or [Entire model/preseTs/Special views] <Entire model>:

  2. Select the Special views option.

    You are prompted: Select view [Exploded view/Unfolded view/Back]:

  3. Select the Exploded view option.

    A dialog box to select the representation and the step appears.

  4. Select the representation.

    You are prompted: Enter new or existing layout name to make current <Layout1>:

  5. If applicable, enter the Layout name of the layout for the representation.
  6. Position the generated drawing views of the representation in the paper space layout.
Note: To use balloons (see the BMBALLOON command) with drawing views of Representations, the GENERATEASSOCVIEWS system variable must be ON.

Update a representation

Run the BMUPDATE command or the Update option of the BMEXPLODE command to synchronize representations with the current state of the assembly.

If applicable, adjust the representation. Such adjustments may be required because of the addition and/or deletion of some parts.

Note: The position of parts in Representations created in Manual and Linear modes are not updated automatically.

Manage representations

Manage representations

Open the Mechanical Browser to see all representations in the document. All representations and sequences will be listed under the Representations group. Open the context menu for the selected representations to see all supported operations in this context:

Note: The Convert all views to new format option is available only when there are old format representations in the drawing.

Properties of exploded views

Each exploded view has a set of properties. You can edit some of the properties.

Property Description
Name Name of the representation. This must be unique for all representations, as well as for all the blocks in the model.
Type Type of the representation: Top or Bottom.
Direction The direction of animation. Choose: Disassembly (from start to end) or Assembly (from end to start).
Auto hide If set to Yes, all unimportant parts for a particular step will be hidden during the animation.
Step duration, s Default duration of each step during the animation (in milliseconds). The default value is 1000, which is equal to 1s duration.
Interval, s Default interval between steps in milliseconds.
Default camera Sets the default camera action.

If Enabled, uses the default camera position and target for all steps which have the Camera set as default.

If Disabled, uses the camera position and target of the previous step for a step which has the Camera set as default.

Operations on representations

The supported operations depend on whether or not the representation is opened for edit.

If the representation is not opened for edit, the following operations are possible:

Operation Description
Edit Opens the representation for edit.
Note: If configured, the custom camera of the current step is used. Otherwise, if enabled, the default camera of the exploded view is used, and if not, the current camera is used.
Tip: You can also edit the representation with the BEDIT command, or by double-clicking it.
Update Synchronizes the representations with the current state of the assembly.
Convert to new format Converts old format representation to the new one.
Note: This option is available only when there are old format representations in the drawing.
Generate views Generates views for the representation.
Delete Removes the representation and the associated block from the document.
Renumerate similar nodes Renumerates representation nodes. Each group of nodes with identical names will have their own numeration.

If the representation is opened for edit, the following operations are possible:

Operation Description
Animate Animates the entire sequence of steps.
Show all parts Shows all parts in the step.
Hide unused parts Hides unused parts from the step.
Save current state Saves the current positions of parts in the current step.
Add a new step after the current Adds a new step after the current one.
Note: The new step will be automatically set as current. All unsaved modifications of the exploded representation will be lost.
Add a new step to the end Adds a new step after the last one.
Note: The new step will be automatically set as current. All unsaved modifications of the exploded representation will be lost.
Update default view from current Updates the default camera position, which is associated with an exploded view itself and not with the initial step. It is possible to have a custom camera for initial step and default camera that are different.
Delete Removes the representation and the associated block from the document.
Renumerate similar nodes Renumerates representation nodes. Each group of nodes with identical names will have their own numeration.
Renumerate child nodes Renumerates similar step nodes of current representation.
Renumerate child nodes continuously Renumerates all step nodes of current representation in spite of names.

In addition, all steps will be listed in the Mechanical Browser for this representation.

Manage representation steps

Open the Mechanical Browser and open the required representation for edit. All steps will be listed under the corresponding node in the tree.

Properties of steps

Property Description
Name The name of the step. Must be unique for this representation.
Duration, s The duration of the step. By default, this is equal to the Step duration set for the representation.
Duration type Specify if the duration must be taken from the representation, or if it is specific for this particular step.
Duration value, s (only for Absolute duration type) The duration for this step in seconds.
Camera The camera position:

Default:

  • uses the Default camera position, if enabled.
  • uses the previous step camera position if Default camera position is disabled.
Camera position (only for custom camera) Display the camera position. By pressing the icon from the right side, user can change the camera position.
Target position (only for custom camera) Display the camera target position. By pressing the icon from the right side, user can change the target position.

Operations on steps

Operation Description
Apply Set the step as the current and update the parts in the representation according to this step.
Note: Double-clicking the step has the same result.
Set view to default Set the camera position for the current step. This camera position will be used as default orientations for generated views for the current step.

If no specific camera position is associated with a step, it will inherit the camera position from the initial step. For newly created exploded views, the initial step will get the same camera position as the model.
Update view from current Update the camera position for the current step.
Animate Animate the step.
Merge Merges two or more consecutive steps.
Split Split the step to a sequence of steps, each of them corresponding to exactly one part.
Move step up Move the step one position up in the tree.
Move step down Move the step one position down in the tree.
Delete Completely remove the step as well as the associated movements of parts. After that, the positions of parts are updated in the exploded representation.
Renumerate similar nodes Renumerates step nodes. Each group of nodes with identical names will have their own numeration.

Edit representations

  1. Select the representation in the Mechanical Browser.
  2. Right-click the exploded representation and select Edit from the context menu.
    Note: As an alternative, you can run the BEDIT command and select the block with the exploded representation.
  3. Perform the necessary operations to get the desired representation.
  4. Save the current step.
  5. Save changes using the BCLOSE command with the option Save.
Note: Do not use the Discard option of the BCLOSE command, as it can lead to an inconsistent state of the block and exploded representation steps. Use Undo instead.

Add trailing lines

  1. Open the representation for editing.
  2. Run the BMTRAILINGLINES command.
  3. Select the subset of parts to create trailing lines for, or select the entire model.
  4. Select the points of the parts to be used in order to create the trajectory: origin or center.
  5. If applicable, edit the resulted trailing lines.
  6. Save changes.