Week 9 - Challenge 3 - Bumper

DESIGN AND DRAFT ANALYSIS OF A CAR BUMPER

Aim -

Create the Bumper Plastic component from the given Class A surface and perform a draft analysis on it. Take the thickness of the component to be 3mm.

Design Methodology -

1. Check the given Class A surface for any discontinuity.

2. Determine the Tooling Axis of the part.
   - Start by checking the surfaces draft through each axis of the component.
   - Select the axis which shows most of the surface and it’s sides clearly while performing a draft analysis.
   - Create a point approximately on the flat surface perpendicular to X axis.
   - Create a line parallel to X axis passing through that point. This is the reference tooling axis
   - Do a Draft analysis of the Class A surface with the reference tooling axis as the draft axis.
   - If the part passes the draft analysis, the reference axis can be finalized as the main Tooling Axis.

3. Create the Class B Surface.
   - Offset the Class A surface inwards by 3mm to account for the thickness of the part.
   - Check the Offsetted surface for discontinuities.

- Make patches for the discontinuous surface. Here, we needed three patches :
At the top part of the Bumper.
At the grill of the Bumper.
At the number plate positioning emboss.

- Add edge blends to the patched surfaces.

4. Create the Class C Surface.
   - Extract the surfaces boundaries which are parallel and perpendicular to the draft tooling axis using multiple extract.
   - Create Swept surfaces to the boundaries :
   90deg to the surface and inwards for the parallel surface’s boundaries.
   3deg With respect to the draft for the perpendicular surface’s boundaries.
   - Join all the swept boundaries to form the Class C surface.

5. Join the Class A surface and the Class C surface.

6. Extrapolate the Class B surface so that the above mentioned joined surface intersects completely with it.
7. Trim the Class B surface with the joined surface to get the closed hollow surface of the component.

8. Use the closed surface command in part workbench to produce the final Solid part.

Isometric View -

Front View -

Side View -

Top View -

Tree Structure of the design process -

Draft Analysis of the surfaces -

Class A Surface :

Final Solid part body :

Isometric View -

Side View -

Front View -

Top View -

Result and Conclusion -

• The desired part is produced by taking the draft requirements and thickness into consideration.
• Draft analysis is conducted on the Class A surface and the final solid part has a positive result.