Week 8 - Challenge 4 - Bumper

AIM:
Create the Bumper Plastic component through the given Class-A surface. To begin with, the tooling axis for the given Class-A Surface should be created meeting the requirements of the draft angle and at the end perform the Draft analysis on the model.

CHALLENGE EXPECTATIONS:

• Tree Structure
• Ensure Proper Tree Structure
• Geometrical sets should have a proper name based on the sketches present inside of it
• All the sketches should be created under the Geometrical set
• Use the Close Surface feature to make a solid body from the surface.
• Publications: Use the publication option and publish the below
  • Tooling Axis
  • Class A, B, and C surface

They are designed to absorb impact to the front and rear of vehicles and minimize low-speed collision damage. Today, standard passenger vehicle bumpers have a rigid reinforcing bar under the outer cover, with sections of compressible foam or plastic underneath.

A bumper is made up of four parts:

• Bumper cover.
• The bumper absorber.
• The bumper reinforcement bar.
• The bumper mounting system.

CLASS A SURFACE CREATION:
Class-A surface means visible surface. It gives the aesthetic of the component which is created by the styling team and gives to the part design engineer to create the part with all engineering aspects.

Tooling axis represents the opening and closing of the mold core and cavity during the manufacturing of the components. A plastic product designer should consider the best tooling direction to cutdown the cost of the component very less.

Method opted for creating tooling axis for the bumper

• Check the best tooling direction for the given surface.
• We can find out the best tooling direction by cross checking all the three axes.

• Here we can find out that the best tooling direction for the pumper class-A surface is along x-axis direction
• The method I choose to create the tooling axis is first extracted a surface and create a midpoint on that surface. The introduced an axis system on that point.
• Then created a with the point and direction along x axis.
• Here both the outer flanges have 5.1-degree draft with respect to the axis created. Hence going with the axis created will not make any difficulties during the draft analysis.
• Another method is by creating intersection along y direction. And then create lines on the walls and then create a bisecting line with the lines on the wall and point created earlier. We will get an axis which will satisfy the draft analysis requirement.

The Draft Analysis is a command enables you to detect if the part you drafted will be easily removed. This type of analysis is performed based on colour ranges identifying zones on the analysed element where the deviation from the draft direction at any point, corresponds to specified values.

Draft analysis is done after determining the tooling axis, draft analysis is used to check whether the minimum draft (3 degrees) is maintained or not.

• Procedure for performing the draft analysis are as follows
• Change the view mode of the component to be in customized parameter mode and then select the shading mode as materials.
• Then open the featured draft analysis tool from the insert menu.
• Then click on use the compass to define the current drafting direction and then drag and align the compass on the Tooling axis.
• Then lock the draft direction and perform draft analysis by clicking on the component.
• The green colour shows the positive daft tooling direction and the given surface passes the draft analysis.
• Click on the analyses under the running point to check the draft analysis on the individual faces. It shows how much draft on specific points when we move the cursor point.

SURFACE-B CREATION

Class-B surface means thickness of a part it is not visible and is inside part. In other words, Class-B surface is a surface below a certain thickness from the class-A surface. This is the surface that contains engineering aspects of a model.

• Offset the class-A surface to 3mm inward direction.
• Rework on the patches and discontinuity of the offset surfaces using the features like multi-extract, extrapolate Trim, Edge fillet, Join.
• To ensure the continuity of the Class-B surfaces check the boundary command to find out the boundary.
• Hence class-B surface creation is done.

Main Operation:-

1. Offset 3mm
2. Join (sub element remove)
3. Multiple extract
4. Extrapol
5. Trim
6. Edge Fillet (not every place see in the class A surface then given )
7. Final Join

SURFACE-C Creation

Surface that joins class-A and class-B surfaces is class-C surface. Class C is often specified for interior surfaces not readily visible, surfaces that will be covered by another part when assembled

Since it is a complex class-A surface, we cannot simply create the class-A boundary curve and sweep it at one shot. Hence, we need to create smaller curves using multi-extract command and then create sweep of 90 degree with reference to the surface option. sweeps at the midportion of the bumper should have a 93 degree vaue to pass the draft analysis.

Main Operation:-

1. Multiple Extract
2. Sweep

Creating the final surface of Bumper

• First step is to join the CLASS-A surface with CLASS-C surface.
• Then Trim the Joined surface with CLASS-B surface to achieve the final Bumper surface