Generate Transition Paths in a Program

task target This task shows how to generate all necessary transition paths between operations in a program. This is done by taking the selected machine's kinematic characteristics and specified transition planes into account.

For more information, please refer to Transition Path Management in the Reference section.

pre-requisites Select File > Open then select the Stepped.CATPart document. You may need to use Fit All In to view the part correctly in the window.

Select Start > Machining and select the desired workbench (Prismatic Machining, for example).

scenario 1. Double-click the Part Operation to display the Part Operation dialog box.

Click Machine and select a generic milling machine (CATProduct). See Machine Editor for more information.

A suitable machine for this scenario is jomach35.1.CATProduct which is a 5-axis machine delivered in:

Click OK to validate the machine selection.

2. In the Part Operation dialog box, click Traverse box planes then select 5 planes that define a traverse box for the part operation.

Note that an arrow that represents the external normal vector is displayed on the top plane of the Traverse Box.
The top plane is the traverse box planes that is perpendicular to all the other planes.
This arrow is be oriented from the plane to the outside of the traverse box.

  3. Click OK to validate the Part Operation parameters.

task target   You may want to position the part on the machine, although this is not necessary for the rest of this user scenario. To do this:
  • double-click the Machining Axis System label in the 3D view. Select the origin point in the dialog box that appears and select the point in the model to reposition the machining axis system on this point
  • select Workpiece Automatic Mount to automatically mount the workpiece on the machine.

Select the Manufacturing Program node in the tree, then create 2 Drilling operations in the program (on Hole1 and Hole9, for example).


Right-click the program and select Compute Tool Path.

6. Select Generate Transition Paths . The Transition Paths dialog box appears. Select the manufacturing program to be processed and set the desired options.

Please refer to Transition Path Options in the Reference section for a description of the proposed options.

    Click OK to validate the options and start generating transition paths.
7. The program is updated with the generated transition paths.

  8. Select the program then select Replay to verify the generated transition paths.

The figure below illustrates that the transition path between the 2 operations respects the traverse box defined on the part operation. Please note that the retract and approach paths are perpendicular to the traverse box planes as specified in the Transition Paths dialog box.

  9. To illustrate the effect of the traverse box with retract and approach paths along the tool axis:
  • select Update Transition Paths to display the Transition Paths dialog box
  • change the Approach/Retract option to Along operation tool axis
  • select the program
  • click OK to update the transition paths.


To obtain the transition path in the figure below:
  • edit the Part Operation to specify an additional transition plane (inclined plane in figure)
  • update the transition path using Update Transition Paths .

More About Generating Transition Paths

  • You can use Remove Transition Paths to remove all generated transition paths.
  • A transition path can include linear transitions and/or machine rotations as follows:
      Linear transition A
      Machine rotation i
      Machine rotation j
      Machine rotation k
      Linear transition B
    Machine rotations can be generated depending on the machine and rotary plane referenced in the Part Operation, and the options selected in the Transition Paths dialog box. A machine with rotary table is required.

    Note that, if needed, transition paths can be deleted and replaced by machine rotations (see Inserting Machine Rotations).
  • If a transition path includes at least one machine rotation, it can be browsed. Just double-click the Transition Path (Ext Rotation) entity in the tree to display a dialog box like the one shown below.

  • The rotary axis name can be set on a generic machine in NC Machine Tool Builder. This allows a better coverage of machines for automatic generation of transition paths (for example, when the rotary axis of the machine is not parallel to the X, Y or Z axis of the absolute axis system).

end of task