Week 12- 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 togehter to obtain the final trim

 

Given Data :

• Class A Surface for Door Trim Panel -

As we know in automotive industry there are complex products that we have to design but this is not possible with simple sketches for that we need Class A Surface.

The A-surface or the styling surface is first checked for any gaps and other issues in its surfaces. This Surface acts as the input surface so any correction to be done should be with approval from the styling team or done by them. A- perfect surface is the one when a boundary is created, the lines are only on the edges of a component and its holes or cutouts as shown below. 

Given class A surface

Rear side of the class A with master section

 

 Creation of Tooling axis for Arm Rest 

1) We have split the arm rest into 2 parts for simplicity of creation. 

The parts were named as arm rest part 1 and arm rest part 2 respectively

Procedure for tooling axis creation 

Step 1: Insert a geometrical set . Extract the base surface and create a point at its center  using point on surface option from point tool. Look for suitable axis to create a tooling axis so that all faces clear tooling . 

Step 2: Create an axis system without current option ticked at the above point. Create a position sketch with zy plane from axis system and above point as reference point.

Step 3: Use intersect 3d objects option from project  tool to create 2 lines by selecting a suitable plane(zy). Now create 2 lines which coincide with lines on both sides of the projection point . Create a line using bisect option .Allign the line in required axis direction.This is our Y tooling axis .  

Step 4: To create tooling axis about x direction, create a position sketch with xz plane as reference plane and projection point as the first point we created . Use cut section tool and create an intersection using projection tool . Now create a line that coincides with this line . 

Step 5 : Draw a line from origin in horizontal direction and create and angle constraint of 5 degrees. Use bisect option to create a line between that above lines . This is out X tooling axis .

Step 6 : Create a new line using bisect option between X tooling and Y tooling line . this is our required Tooling Axis , Name this as tooling axis and publish it . 

 Procedure to check for Draft analysis

1)Once the tooling axis is created , publish it and the component using Publication from tool option . 

2)Insert Feature draft analysis option from insert tool bar

3) Change the view option to customize view parameters and click on material option under shading . 

4) Now click on the axis option from Draft analysis tools , allign it with tooling axis and click on lock option to lock it . 

5) Change draft angle value to 3 degree . Click on quick analysis mode to display feature according to given color scale . Check from all views to ensure the draft analysis is cleared . 

6) Since the created tooling axis does not clear the draft analysis at the created axis , click on the lock axis button to unlock it . Now  rotate the tooling axis by left clicking on the top round portion of the axis system . Rotate the axis till maximum clearance is obtained . Now right click on the axis and click lock current axis . 

7) Create a line using the initial axis origin and this axis using point and direction (using compass direction) option . This is our required tooling axis . 

8) Now if we check for draft analysis, we can observe that the ribbed area has not yet cleared draft analyisis. Hence we need to create a side core tooling axis . To do this , create a line using point and direction option with Y direction . 

9) Repeat steps 1 to 5 to ensure the remaing portion which was not cleared using Tooling axis has been cleared using this axis . 

Similarly created tooling axis using same procedures for all other components . 

Tooling axis for Arm rest part 2

Tooling axis for lower substrate

Tooling axis for Map pocket upper 

Tooling axis for map pocket lower

Here we can observe that regions in blue colour has a 0 degree draft angle . This would lead to ejection problems while molding process . Hence the class A surface has to be modified to meet draft requirements . 

Hence we have created tooling axis for all components . 

2) Creation of class B surface 

Procedure to create class B surface for Lower substrate .

Step 1: Use offset tool with a distance value of 2.5mm to create offset of class A surface . 

Step 2: After offsetting , extrapolate tool was used to extend all the edges of this surface . This is done to ensure that the parting line comes at B surface . 

Step 3: In areas where extrapolate was not possible (Fillet or cusped surfaces)  multisection surface option was used . 

 

Step 4: Join all the extrapolated surface and multi section surfaces to obtain a single surface . 

Hence the class B surface was created for lower substrate . 

Similarly , class B surface was created for  other components . 

Class B surface of arm rest  PART 1

Class B surface of arm rest PART2

Class B surface of map pocket upper

Class B surface of map pocket lower 

Hence class B surface for all components were created . 

3)  Creation of Class C surface 

Procedure for creation of class C surface for Upper map pocket 

Step 1: Use sweep command to create a new surface an an angle with respect to a surface . This angle is dependant on draft angle for free edges and ususally 90 degree for mating surfaces . 

 

Step 2: In areas where sweep is not possible , use Multi section surface to create a new surface . 

Step 3: Join all surfaces to obtain C surface. 

Hence C surface was obtained for upper map pocket

Similarly C surfaces were obtained for all other components . 

C surface for Lower map pocket . 

Class C surface for Arm rest part 1

Class C surface for Arm rest part 2

Class C surface for Lower substrate 

Hence  class C was created for all components . 

4) Creation of closed body

Procedure for creation of closed body for lower map pocket . 

Step 1: Use trim or join option to join Class A and Class C . 

 

Step 2: Use trim option to join above trim with class B 

Hence we have obtained closed body . 

Similarly closed body was obtained for all other parts

Closed body for upper map pocket

Closed body for Lower substrate 

Closed body for Arm rest part 1

Closed body for Arm rest part 2

Hence we have created closed body for all parts and thus we have created solid bodies from them . 

5) Draft Analysis 

Procedure to check Draft analysis for Lower substrate . 

 

1)Once the tooling axis is created , publish it and the component using Publication from tool option . 

2)Insert Feature draft analysis option from insert tool bar

3) Change the view option to customize view parameters and click om material option under shading . 

4) Now click on the axis option from Draft analysis tools , allign it with tooling axis and click on lock option to lock it . 

5) Change draft angle value to 3 degree . Click on quick analysis mode to display feature according to given color scale . Check from all views to ensure the draft analysis is cleared . Click ok to complete the Draft analysis mode. 

Draft analysis for Map upper pocket

Draft Analysis for Arm rest part 1

Draft Analysis for Arm rest part 2

Hence we have completed first part of the project and have obtained closed body for all the parts clearing draft analysis

PART 2 : Attachment of flanges using given master sections . 

Procedure to create flanges and heat stakes for Arm rest part 2 from given master sections .

Step 1: Use multiple extract to obtain required guide curve and sweep profile for flange top surface . 

Step 2 : Use sweep option to create a surface from below obtained multiple extracts . 

Step 3 : Use extrapolate to extend the surface according to master section and create a solid body in a new body . Create holes and flat surfaces for heat stake .

Step 4:Heat stake was created from padding a sketch created from a point obtained from master section.

Step 5: Stake support was created using  padding the multiple extract from master section and thickening it . 

Similarly features were created on all parts according to  master section . 

Flanges on upper map pocket

Hence we have made features according to master section. 

3) Creation dog dog house and additional attachment features according to industry standards. 

Procedure to create dog house on lower substrate 

Step 1: Create a point on required location and a plane from it . Create a sketch with base sketch for dog house . 

Step 2: Use sweep tool to create a surface using this profile and draft direction at a draft angle of 1.5 degrees . 

Step 3: Use extrapolate and extrude option to create required surfaces and use trim and split to obtain the outer body of dog house . 

                                                                                                                  

Step 4: Create a new body and name it as dog house 1 . Use thick surface option to create a solid of required thickness .

 

Step 5: Translate the dog house to required height using translate option and use thick coomand to extend the base surface to intersect the lower substrate. 

Step 6: Extract the inner base edge and create a surface to get the required base profile . Use thick surface to create a solid and use boolean operation to remove it from the base of dog house. 

 

Step 7 :To create top profile for attachment of push pins , create a stech , extrude it and split it from the solid using split option

Step 8: To create a base for push pins to rest , create another sketch extrude and off set it . Create solids feom it using thick surface option . 

Use boolean operation union trim to obtain required design.

Thus we have created dog house .

Step 9: To create ribs, create and sketch and use pad tool to create a solid and union trim it with dog house .

 

Now we have made complete dog house with ribs . Use translate option to position it in required locations . 

Procedure to create ribs on Heat stakes

Step 1: Create a sketch with center as centre of heat stake inner circle . 

Step 2: Use pad option to create solid body

Step 3: Use boolean opetaion union trim to obtian required ribs.

Procedure to create ribs on lower substrate 

Step 1: Create a sketch and create a surface . Use thick surface option to obtain ribs in required shape .

 

Step 2:Use Translate option to place ribs wherever required. 

Step 3: Use Boolean operation union trim to trim it with lower substrate main body . 

Create heat stakes and flanges at required locations using above mentioned procedures to obtain complete substrate body . Apply draft on all required surfaces  and fillets on all straight edges.

 

Final Upper map pocket

Final Lower map pocket

Final Hand rest part 1

Final Hand rest part 2

Draft analysis for Completed parts

1) Hand Rest Part 1

2)Hand rest part 2

 

3) Lower Substrate

4) Map upper pocket

5) Map Lower pocket

CONCLUSION : 

From this project I have leraned how to create CAD model for plastics parts by considering design rule. By doing this project on Catia V5 , I get very well familiar with part workbench ,surface workbench , Assembly workbench. Also I get confidence in handling different features of all workbenches. Along with this , I get idea of how to design a part by considering manufacturing and assembly aspect.