Week 8 - Challenge 4 - Bumper

Aim :- The objective of this report is to 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.

Introduction :-

• A bumper is a bar attached transversely in front of or behind a car body to prevent contact between an obstruction and the car body or to cushion the shock of collision between vehicles.

• A bumper is made up of four parts:

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

• Modern consumer production cars have almost completely switched over to plastic bumpers. Modern car bumpers are made from thermoplastic olefins, a blend of plastic molecules, rubber, and a reinforcing filler like carbon fiber or calcium carbonate.

• This blend of materials creates a scratch and impact-resistant plastic that can bond with a wide range of paints and finishes, making it ideal for vehicle bumpers.

• Plastic is the preferred material for modern car bumpers for several reasons. First and foremost, plastic is much lighter and more aerodynamic than metal, which improves the car's fuel efficiency.

• Plastic is also easier to shape, which is useful during both the manufacturing and bumper repair process.

Procedure to Design Bumper in Automotive Industry :-

• To design Bumper as per automotive industry Standard.
• Create tooling axis for the given CLASS-A surface.
• Create B Class and C Class surfaces
• Create final surface model and convert it into solid body using close surface command in the part design workbench.
• Perform draft analysis for both Class-A surface and Final part body.

DESIGN METHODOLOGY :-

• The Class-A Surface would be provided to us by the styling team of the OEM.
• Class-A surface means visible Styling 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.

• The first step is to check the continuity of the class A surface. This is to ensure that there is no gap between surfaces.

• If we find any gap then we should fix that first.

• We can analysis the class A surface through visual inspection.

• To make sure that the given surface has no gap in between them. We can check it through the help of Join or boundary commands.

Procedure for creating the tooling axis :-

• 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 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 the normal to the Surface.
• Hence going with the axis created will not make any difficulties during the draft analysis.

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 extract, multi-extract, sweep, multi-section surfaces, extrapolate.
• 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.
• Then Publication the Class-B surface.

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 boundary command and then create sweep of 90 degree with reference to the surface option.

Creating the final Bumper surface :-

• 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.
• Switch to the part design work bench and using the close surface command to create the Bumper solid part body.

Draft Analysis :-

Class-A Surface :-

• The Draft Analysis is a command enables you to detect if the part you drafted will be easily removed or Not.

• 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.

Draft analysis of Class-A:-

Draft Analysis Of final Solid Body :-

Tree Structure of the Bumper Design :-

Conclusion :-

• Now Bumper is Created accroding to the Design rule using in the Automotive industry.