Week 12- Final project

Week 12 challenge:

Final project Development of a Door Trim panel

AIM

To create a CAD model for door trim panel's parts by considering the given inputs of class A surface along with master section by following the design rules followed in OEM and tier1 companies.

Objectives

• To create individual tooling axis for the parts and perform draft analysis on the class A surface
• To create the class B and class C surfaces from the given class A surface
• To form a solid geometry by combining all the surfaces
• To decide an attachment strategy for the part and create engineering features in reference from the master section provided
• To perform draft analysis on the solid part model with all engineering features
• To assemble all the components together to obtain the final trim

Introduction:

Door Trim Panel

Door panels serve as an interface between the interior of the car and the inner workings of the door, and between vehicle occupants and the door. They are expected to meet a variety of design specifications regarding safety, aesthetics, and functionality. In addition, they are expected to continue the material theme of the dashboard and pillars while concealing intricate electrical and mechanical components for operating locks, windows, and other features. The door panel has evolved from a simple two-part system of latch and simple winding mechanism to a more sophisticated enclosure. Doors currently have an inner full-width panel consisting of electronic windows, central locking system, and speakers. These panels typically consist of a foamed core covered with either textiles or plastics. Plastics is the core and soul of the door trim interior, one must have knowledge about the plastic being used and its cost associated with the molding and manufacturing.

Introduction to Door Trim Panel Plastic Component Design in CATIA V5

Door trim panels, often composed of plastic components, play a crucial role in automotive interiors. They contribute to both aesthetics and functionality, influencing passenger comfort, noise reduction, and overall vehicle appeal. Designing these components in CATIA V5 involves a specific workflow and considerations.

Here's an overview of the key aspects:

1. Importance of Door Trim Panels:

• Aesthetics: Define interior styling and brand identity.
• Functional requirements: Provide armrests, storage compartments, speaker mounts, and access to door controls.
• Safety: Contribute to crashworthiness and noise reduction.
• Manufacturing: Optimized for cost-effective production techniques.

2. Design Workflow in CATIA V5:

• Concept sketch and Class-A surface creation: Establish the primary aesthetics and form using sketches or imported surfaces.
• Solid modeling: Build the 3D volume based on the Class-A surface, considering thickness, draft angles, and manufacturing constraints.
• Feature creation: Add elements like ribs, bosses, and mounting points using specific CATIA V5 features.
• Assembly and analysis: Integrate the door trim panel with other interior components to check for fit and potential clashes. Perform FEA simulations to assess structural integrity and noise vibration harshness (NVH) characteristics.
• Documentation and drawing creation: Generate production drawings with dimensions, tolerances, and material specifications.

3. Considerations for Plastic Components:

• Material selection: Choose plastics with appropriate strength, flexibility, heat resistance, and surface finish.
• Draft angles: Ensure proper angle for mold release during manufacturing.
• Rib design: Add ribs for structural reinforcement and stiffness without compromising aesthetics.
• Snap fits and heat staking: Design efficient joining methods for assembly and cost reduction.
• Tolerances: Define realistic dimensional tolerances for manufacturing feasibility.

4. Resources and Further Learning:

• CATIA V5 documentation: The official CATIA V5 documentation provides detailed information on specific features and workflows.
• Tutorials and Online Courses: Many online resources offer tutorials and courses on door trim panel design in CATIA V5.
• Automotive design blogs and communities: Engage with communities dedicated to automotive design for insights and best practices.

Class-A surface:

The Class-A surface is the outermost surface of the plastic component which is also looks fine surface and it is the aesthetic surface that the designer creates as an input part for the design work

Class-B surface:

The Class-B finish is a quality finish with only minimal imperfections. A Class-B finish is the most common finish for exterior surfaces. It is normally specified on surfaces such as external covers, panels, and parts that are fairly prominent.

Class-C surface:

The Class-C finish allows more imperfections than Class-A or Class-B. Class-C is often specified for interior surfaces not readily visible, surfaces that will be covered by another part when assembled, or surfaces which the Customer feels do not need to meet a high cosmetic finish.

Tooling Axis:

In Molding, machine arrangement is given to open the mold along a direction which is known as Tooling Direction. In other words. The mold is built from two separate halves (Core and Cavity) and tooling direction basically defines the direction of mold or core pulls apart.

Draft Analysis:

The Draft Analysis command enables you to detect if the part you drafted will be easily removed. This type of analysis is performed based on color ranges identifying zones on the analysed element where the deviation from the draft direction at any point, corresponds to specified values. Most parts or applications require minimum of 1/2 to 1 degree however 3 degrees is widely accepted as the norm.

Design Methodology:

Components of Door Trim panel:

1. Arm Rest
2. Lower Substrate
3. Upper Map Pocket
4. Lower Map Holder

For each part:

• Class A surface was analyzed first.
• Some corrections were made in class A surface first.
• Tooling Axis was created.
• Draft analysis was performed.
• Then Class B surface was made by offsetting the corrected Class A surface.
• Class C surface was made by using the edges of the Class A surface. Then Class A and C were joined together.
• Now this A+C and B surface were trimmed together. This results in a closed surface.
• Then this final trim was thickened in Part Workbench.

1.Arm Rest:

Class A:

Class B:

Class c:

Closed Surface A+B+C

Draft Analysis:

2.LOWER SUBSTRATE

Given Class-A Surface

Class-B Surface Creation.

Class C surface:

Closed Surface A+B+C

Draft Analysis:

Creation of Dog House.

General Guide lines for Dog House:

• "C" is where the doghouse contacts the backside of the surface.

• Doghouse wall thickness at the intersection of the part wall ( C ) should be 40% or less than the main wall stock ( T ).
• The height of ( B ) should be between 3.0 – 6.0 mm.
• Minimum Doghouse Width (X) for doghouses is 12 mm.
• Minimum Draft (D) for doghouse is 1.5 degree* to die draw.

3.Map pocket:

Class A Surface:

Class B surface:

Class C surface:

Class A+B+C

Flanges

Draft Analysis:

4.LOWER MAP HOLDER

Class-A Surface.

Class B Surface:

Class C surface:

Class A+B+C:

Flange:

Draft Analysis:

5.PUSH PIN

Push pin which heilp us locating and arresting component of an assembly and it provide alignment in mating parts and also act as various guide of mechanism. They are bascially attached to the dog house.

Conclusion

Thus the Door Trim panel CAD model is created considering the design rules as like in OEM and tier1 companies.

• Thickened part using the master section for reference was created.
• The mounting features such as 4-way locators, heat stakes, and flanges as per design guidelines were created. In the bottle holder, the flanges are intersecting with the part body despite being created using the design rules, and hence changes in the design of Class A surface are needed.
• Dog houses and the push pins were assembled.
• Draft analysis was performed.
• Plastic material was added.