Week 11 - Final project

Aim:

To create a CAD model (Door Trim Panel) with attachment features considering the given inputs, design rules and following the OEM standards.

   This Project explain in brief regarding the Design life cycle followed in automotive industry by working on Practical Model car interior door trim which is a Car interior trim Part.In this Report we have explain about the steps followed to create a solid body of the piller Cover taking Class A Surface as Input and Creating a Tooling axis and B surface with resect to the Class A Surface and Creation of Class C Surface and also the Draft Analysis.The attachment features also designed and reported as per given master section considering all the design rules for the creation of  ribs and doghouse.

What is Master Section?

Master sections are the guides for design requirements which decide the component packaging after technical (Styling, Concept or Class-A) surfaces.

Following is the general workflow that is followed for the design and development of interior and exterior automotive trims in OEMs.

The styling and design teams at automotive OEM’s always walk an extra mile to make the best looking interior and exterior automotive trims. But, when it comes to engineering for feasibility study, there are various constraints that are not well thought and analyzed due to time constraints. As a result, the best-looking styling gets compromised in the production vehicle. Above shown workflow the initial activity of styling and Class A Surface modelling is done by the client and the rest of the activity is done by ASI with client representatives at every stage of development.

To support OEM’s overcome such challenge of delivering competitive and superlative quality automotive trims, we have come up with a methodical approach that focuses on the major selling points of the vehicle. The approach is explained through following 3 blogs:

Block-1: Class A Surface engineering feasibility check & feedback.

Block-2: Matching concept design in detail.

Block-3: Master sections, Detailed Design considerations, B-Surface Modelling, Supplier Feedback & drawing release.

 

OVER VIEW OF DESIGN LIFE CYCLE:

• Reserach

        The research design refers to the overall strategy that you choose to integrate the different components of the study in a coherent and logical way, thereby,ensuring you will effectively address the research problem; it constitutes the blueprint for the collection, measurement, and analysis of data.

• Design Requirements:

        The design requirements for a product are based on the wants and  needs of the intended customer. These wants and needs must be identified by the company making the product, and they are often communicated by the target customer in nontechnical and sometimes vague terms.

• Feasibility:

        In some cases, a feasibility study is carried out after which schedules, resource plans and estimates for the next phase are developed.he feasibility study is an evaluation and analysis of the potential of a proposed project to support the process of decision making. It outlines and analyses alternatives or methods of achieving the desired outcome. The feasibility study helps to narrow the scope of the project to identify the best scenario. A feasibility report is generated following which Post Feasibility Review is performed.

• Concept Generation:

        A concept study  is often a phase of project planning that includes producing ideas and taking into account the pros and cons of implementing those ideas. This stage of a project is done to minimize the likelihood of error, manage costs, and evaluate the potential success of the intended project. In any event, once an engineering issue or problem is defined, potential solutions must be identified. These solutions can be found by using ideation the mental process by which ideas are generated.It can be done normally by Clay Modelling. 

• Prelimnary/Class A Surface Design:

        The preliminary design, or high-level design includes  often bridges a gap between design conception and detailed design,particularly in cases where the level of conceptualization achieved during ideation is not sufficient for full evaluation. So in this task, the overall system configuration is defined, and Schematics, diagrams,and layouts of the project may provide early project configuration.During detailed design and optimization, the parameters of the part being created will change, but the preliminary design focuses on creating the general framework to build the project on.This is also Called as CLASS A SURFACE DESIGN.Styling or A class surface are the terms used in plastic product design. That mean the surface of a component which is smooth( aesthetic) or visible side to human eye after the part is assembled.Class A Surface of the interior door trim is as shown in picture below:

 

Procedure:

 

THE GIVEN INPUT IS DIVIDED INTO 5 PARTS

• Lower Substrate
• Map Pocket Upper Part
• Map Pocker Lower Part
• Arm Rest Upper Part
• Arm Rest Lower Part

Methodology:

• CLASS-A surface extraction
• Creation of different Geometrical sets for each component such as lower substrate, map pocket (upper & lower part), armrest (upper & lower part), etc.
• Tooling Axis / Side Core Axis Creation
• Creation of Flanges
• Creation of CLASS-B Surface
• Creation of CLASS-C Surface
• Joining of CLASS-A, B & C Surface
• Performing a check for boundaries
• Forming a Solid Body
• Attachment features creation
• Performing Draft Analysis

1. Lower Substrate:

CLASS-A surface extraction:

Initially, we need to extract the CLASS-A surface for the Lower Substrate from the given input.

 

TOOLING AXIS:-

The purpose of toolin axis is basically the direction that the mold opens. The mold is built in two separate pieces, these are core and cavity. The Core and cavity moves along  the Tooling Direction. There are different methods to find out the tooling direction. Here we are using bisecting method to find out tooling direction. We can use any method. but our main aim is to reduce the cost of manufacturing by reducing the complicity in manufacturing the component.

Then create the tooling axis for the lower substrate. your tooling axis must clear the all faces of ur lower substrate. and it is checked by draft analysis.

 

DRAFT ANALYSIS:-

The Draft Analysis command enables to detect if the part you drafted will be easily removed from the core and cavity. This type of analysis is performed based on color ranges identifying zones on the analyzed element where the deviation from              the draft direction at any point, corresponds to specified values.In Draft Analysis, the Class C surface side walls are checked for draft. A minimum  3 degrees draft is expected on the component to make it manufacturable without any damage to the product. and it is eaisily withdrawl from the core and cavity after manfacturing.the draft analysis gave a report whether the tooling axis can clear the all faces of the parts.some times it cant cler the all faces due to complexity of the part. so side tooling axis are used to clear that face.for that a side cores are used to manfacturing the compopnent.

PROCEDURE:-

• To perform the draft analysis the view parameters are first set to material mode.
•  Then go to Insert >>analysis>>feature draft analysis.the fallowing window will be appread

 

 

• First, select the axis system and drag the axis system to the tooling axis and lock the orientation. This axis system defines the draft direction according to the tooling axis.
• Switch on the color scale and set the draft value 3° using colour scale. and it will be displayed in green color. Any draft angle below 3 degrees will be shown in red color.
• Here, the compass direction is rotated to have the positive direction in the maximum portion of the part. Then the compass is locked in the orientation and a new tooling axis is created using the compass as the direction.
• Now select the running point tool to measure the draft angle at the various locations and then if all surfaces pass the draft analysis switch on the light effect that will show the component in green color if the component has the required draft angle.

CLASS-B surface:

To create the CLASS-B surface, the CLASS-A surface is offset by 2.5mm (since the thickness of the component is 2.5mm). From the master sections which is given to us as input, we can measure the thickness of the component.

CLASS-C surface:

To create a CLASS C surface first extract the boundaries of the CLASS A surface.

After extracting the boundary, we need to perform a smooth (max. Deviation as 0.001mm) operation on it to create a continuous tangent surface.

Now using the ‘sweep’ option create the C surface by sweeping the boundary of the CLASS-A surface at an angle of 3deg outwards to the tooling direction.

And them trim it from the class a to get the thickked lower substrate.

Forming a Solid Body:

Since these surfaces are hollow, we need to close them to form a thick solid component. 

Using the “CLOSE SURFACE” option in PART WORKBENCH, a solid body from the closed surface can be formed.

 

2. Map Pocket Upper and Lower Part:

CLASS-A surface extraction:

Now again from the input which was given to us, we need to extract the CLASS-A surface for the Map Pocket Upper and Lower Part separately in a different geometrical set.

LOWER PART

TOOLING AXIS

DRAFT ANALYSIS

CLASS-B surface:

CLASS C SURFACE

Solid Body:

Creating Flanges:

Flanges are needed to join the components. Following the master sections, we can create these flanges and attach them to the solid body.

 

UPPER PART

CLASS A SURFACE

TOOLING AXIS

DRAFT ANALYSIS

CLASS B SURFACE

CLASS C SURFACE

SOLID BODY

Creating Flanges:

Flanges are needed to join the components. Following the master sections, we can create these flanges and attach them to the solid body.

DOOR MAP POCKET UPPER PART WITH FLANGES

Arm Rest Upper Part and Lower Part:

To create the surfaces and forming a close body similar steps need to be performed as mentioned for the above parts. But to create a proper tooling axis for Arm Rest Upper Part, we need to adjust the tooling axis since this component cannot be cleared in 90 deg to any (X, Y & Z) of the directions.

For the Arm Rest Lower Part, a side core axis is also required along with the main tooling axis.

LOWER PART:

CLASS A SURFACE

TOOLING AXIS.

in this case the main tooling axis doesent clear the all faces of the part. so we need sliding axis for clear the pocket area in door arm rest

MAIN TOOLING AXIS

SIDE TOOLING AXIS

DRAFT ANALYSIS

CLASS B SURFACE

CLASS C SURFACE

SOLID BODY

DOOR ARM REST UPPER PART

CLASS A SURFACE

TOOLING AXIS

DRAFT ANALYSIS

CLASS B SURFACE

CLASS C SURFACE

FINAL BODY

Creating Flanges:

Flanges are needed to join the components. Following the master sections, we can create these flanges and attach them to the solid body.

Attachment features creation:

Heat Stakes:

Heat stakes are used to join two or more parts that are made of plastic with the help of the heat staking process. The heat staking process involves the deformation of the plastic material using heat and force to fix it with the other parts.

To create the Heat Stake, we need to create a sketch with a circle of diameter 8mm. Now extrude this sketch to a height such that it is passing through the Flange. Using the shell option, thicken this extrude (thickness 2mm) to form a solid and give it a draft of 0.5 deg.these heat stakes are designed as per the design rules.

 

 

Points are needed to position these heat stakes. Once all the points are created, the solid body of the heat stake can be copied and paste on the tree structure multiple times (depending on the requirement, heat stakes need to be copy-paste). 

Now using the translate option move these heat stakes from one point to another

Dog House:

The Dog House is an engineering feature that is used in the plastic trim design. It is used as a supporting feature for other engineering features like snaps, locators, push pins etc. that are mounted on the Dog house to increase their strength and also to avoid the sink marks.

To create the Dog House, we first need to create a sketch that is rectangular with one side is open and then extrude it.

Now using thicken option in PART WORKBENCH, give it a thickness of 2mm to form a solid.

To get the inner shape of the Dog House the following Design Rules are followed.

TOOLING AXIS AND DRAFT ANALYSIS

Push Pins:

Push Pins are used for joining one component to another and are attached to the Dog House.

To create a Push Pin a sketch is drawn following the below details.

DOG HOUSE WITH PUSH PIN

DOH HOUSE WITH PUSH PIN ON DOOR LOWER SUBSTRATE

DOH HOUSE WITH PUSH PIN ON DOOR MAP POCKET

DRAFT ANANLYSIS ON DOOR LOWER SUBSTRATE

DRAFT ANANLYSIS ON DOOR ARM REST

LOWER PART

UPPER PART

DRAFT ANANLYSIS ON DOOR MAP POCKET

DOOR TRIM

TREE STRUCTURE

Result:

A Door Trim Panel with engineering features using the master section and surface as an input has been successfully created and draft analysis has also been performed for the same.