Tutorials:3D Flattening Workflow

OptiTex's new technology enables on-screen transformation of three-dimensional objects' surface into two-dimensional patterns. Sketch on the 3D models and receive instant feedback in 2D production patterns. The technology is applicable to a broad range of industries and applications, including textile and manufacturing, car seats for the automotive industry, aeronautics, film making, computer gaming and more.

Introduction & Objectives

The objective of this tutorial is for you, the reader to obtain basic 3D Flattening skills, meaning the ability to draw sew lines directly on a model and receive 2D production patterns. This tutorial will not cover every button and command in the system, but it should help you obtain a good knowledge of the workflow and a better understanding of the system.

Model Requirements

OptiTex's Flattening solution supports scanner output as the sketching target as well as imported models created by various systems. However, there are some requirements for the models to work smoothly with the 3D Flattening tools.

1. The input mesh has to be a single manifold mesh. Meaning that a model which its polygons are separated would have to be welded (united) first.
2. Areas where there are polygons which "stick out" of the main surface will not be processed by the tool.
3. The ability to draw Flattening lines is also a subject of proper tessellation, meaning:
   1. No long or wide faces
   2. Triangles' area shouldn't vary greatly
   3. Extremely small triangles will not be processed by the tool

• The following images show examples of models that do not meet the requirements:

1. Non-manifold mesh in the belly button area, small polygons are sticking out of the main surface

2. Big faces in the lower part of the armchair

3. Extremely small polygons

4. Triangles' areas are too diverse

5. Odd topology

Model Pose

For maximum ease of use of the Flattening tools it is recommended to use the following morphs in the Model Properties window (when using models provided by OptiTex):

1. In Shape folder move the slider next to Crotch Flatten to maximum value.
2. In Pose folder move the slider next to Arms Pose to maximum value.

5. Arms close to the body

6. Arms far from to the body, easier to draw around the torso

7. Buttocks crack is normal

8. Buttocks crack is flattened, easier to draw on

Step 2: Drawing 3D Lines

After setting the symmetry guide lines you can start sketching your design. First draw the symmetry lines.

Drawing Symmetry Lines

1. Select the Draw Path tool from the 3D Flattening Toolbar
2. Click & Hold the left mouse button to place a pin and move it exactly to the center axis of the model while holding Ctrl+Shift keys. The pin will snap to the center axis and change its color to blue.
3. Continue drawing the symmetry line until you have the Center Front and the Center Back marked on the mannequin. It is recommended to work in a fixed direction (top to bottom for instance).
4. It is recommended to save the mannequin with symmetry lines in your model's library so you won't have to sketch them again each time you start a new design.

13. Center Front line

14. Center Back line

Drawing The Design

1. Select the Draw Path tool .
2. You can start drawing your design from the symmetry line. To do that snap to an existing pin or to an existing line in order to create a new pin on this line.
3. Continue drawing. If you need to rotate around, click on the keyboard shortcut F. The highlighted pin (the last created one) will now be in the center of the focus and you'll be able to rotate around it.
4. To rotate while using the Draw Path tool, hold the Ctrl key and use the mouse to navigate in 3D.
5. To delete last created pin/pins without exiting the Draw Path tool, click on the Delete key. The highlighted pin will be deleted and you'll be able to continue drawing from the previous pin.
6. If an Error Message pops up during the drawing, follow the indicated instructions.
7. Save the model.

Reviewing And Editing Lines

Review the lines you created.

1. To delete a pin or a line Ctrl+Click them and press Delete.
2. To select multiple pins use the Shift key.
3. To reshape a certain curve between two pins or move a pin use the Edit Pins tool
4. If not possible to properly reshape the curve, add more pins on the line with the Draw Path tool.

• Notice that adding a pin to a line after changing the curve with the Edit Pins tool, changes the line's shape (see example bellow).

Copy Half

If you wish to have the lines drafted on one side of the model to be copied to the other side, use the Copy Half command .

Step 3: Building Patches

After finishing the 3D drawings, you should have closed boundaries which could be defined as Patches. A Patch is a 3D shape which would later be transformed to a 2D piece.

1. Use the Build Patch tool to create a patch from a closed boundary.
2. If an Error Message pops up during the creation of patches, follow the indicated instructions.
3. Common troubleshooting
   • See example bellow for checking that an area is properly closed:

• Notice that moving a pin after building a patch will delete the patch.

Step 4: 3D Baseline And Notches

3D Notches

Use the 3D Notch tool to place notches on relevant pins and lines. The notches will be used later on 2D to align pieces, mark pieces that should be sewn together and to mark textures' adjustments.

• The 3D Notches can be set before and after the creation of patches.

3D Baseline

Use the 3D Baseline tool to set the baseline direction for each patch you created in the previous step.

Step 5: Flattening Patches

• Use the Build Patch tool to flatten a patch to a 2D pattern piece. The pattern piece will be displayed on the Pieces Window.
• Each 3D pin will be translated into a grading point. Non-grading points will be created between the grading points to support the translation of lines and surfaces from 3D to 2D.
• For patches with no 3D Baseline direction, a default baseline will be created on the pattern piece.

Step 6: Editing On 2D

1. Place all pieces on the working area, either one by one or through the Edit menu and All To Working Area.
2. Save the PDS file.
3. Select All (Shortcut Ctrl+A).
4. Use the Points Cleanup command from the Piece menu (Shortcut Ctrl+Q) to reduce the number of support points created in the Flattening process.
5. Give name, quantity and Pair attributes to each piece.
6. Use the Set Half tool to create symmetrical pieces (mainly used on Center Front and Center Back).
7. Use the Walk Tool to compare pieces that should be sewn together.
8. Use the Align Points Tool to align straight lines in a fixed angle.
9. Add seam allowance to the pieces using the Seam Tool or the Set Basic Seam command.
10. At this point you can stitch the pieces together and perform a 3D simulation of the product on the 3D model. For complete work flow of 3D draping see Getting Started On 3D Stitching.

Keyboard Shortcuts

• Ctrl+T - Show/Hide Textures