Week 12- Final project

                                                                                                    Door trim lower panel-Final project

Aim: In this project we create the door trim panel Components that is (Lower substract,Arm rest, Bottle holder, map pocket) with the necessary input surfaces provided and generating the necessary B side features ( heat stakes, 4 way locators, Dog houses, push clips, Ribs, screw bosses etc) thereby  assemble  the individual components of the door trim by providing proper constraints  there by performing the proper draft analysis using catia V5  software

Objective :

The main objective is to create the individual components of the door trim with input class A surface provided and generate the class B and class C surface and produce the solid surface body out of it and perform the proper draft analysis with required draft angle of 3 degrees for the body and continue the procedure for the remaining components .Then start creating the B side features of the components by following the reference of the master sections  provided and perform the draft analysis with an input draft angle of .5 degrees and assemble the components to for the final door trim panel on the assembly workbench by providing necessary constraints using catia V 5 software

Procedure followed for the creation of the components:

1. Analyse the input surface  provided
2. Class A surface as input surface
3. Tooling axis creation
4. Draft analysis of class A surface
5. Class B surface creation
6. Class C surface creation
7. Solid surface body generation
8. Draft analysis of the solid body
9. creating the B side features 
10. Draft analysis of the solid body along with the B side features .

Class A surface:

Class A surface is an asthetic surface which is visible for the customer in the component

Class B surface:

Class B surface is an engineering surface where the B side features of the components like heat stakes, screw bosses, Ribs, doghouses are situated

Class C surface:

Class c surface lies as an intermediate surface between the class A and the class B surface thet means it generally accommodate the thickness of the whole plastic component

The input provided for the design is 

Arm rest design

In the front of the car, a central armrest, which commonly folds away based on user preference, will also often include a storage compartment and sometimes even cup holders. Some also provide the location for controls for non-essential functions of the vehicle, such as climate control or window motors.

For the Arm rest design the input class a surface provided is 

To check whether the surface has any oen boundaries use the boundary feature then we can identify that there is an open patch or the surface which we need to work on 

This is the poen patch we got from the boundary feature 

After complete working on the open patch check the boundary of the surface to confirm whether there may be any possibility of the open surfaces .Then name the obtained surface as the class A surface and start working on it

This is the updated class a surfcae with no poen patches from the boundary feature.

Tooling axis creation:

In case of the arm rest we generally deploy the bisection methiod for creating the tooling axis , that is first we need to create a plane and form an intersection of the surface and generate the two lines from the intersection and there by creating a line by using the bisection method

This is the main tooling axis

Now step forward to create the side tooling axis use the point -direction method for creating the side tooling axis 

Draft analysis of the class A surface:

Once the creation of the tooling axis is done perform the draft analysis of the class A surf ae whether all the surfcaes of the clsss A is cleasring the draft analysis or not 

General draft angle provided on the plastic engineerng componenet is 3 degrees

Here some of the surfcaes of the class a surfcae cannot be able to claer  the draft analysis with respect to the main tooling axis so , either you should report to the concerning team to update the draft on the uncleared  surfaces or continue it

The red patches on the drafted surface indicates thet theb  draft on the surfaces is less than 0

Generating of the class B surface

For the class B surface generation refer to the master section provided to measure the thickness of the plastic component then offset the class A surface to an extend of 2.5 mm thickness beneath the class A surface

Extrapolate then class b edges to an extent to form the proper trim with the class a & C join

Generating the class C surface:

For the class C surface generation we use the class A surface  as an reference and follow the draft with respect to the reference surface and the main tooling axis

Generating the final close surface:

After creating the class B and the class C surfaces join the class A and the class C surfaces and trim the resultant with the class B surface then the resultant surface is the final closed surfaces

Then make the B surface trim with the class A & C join

It is the close surface of the plastic componenet with a thickness of 2.5mm

Then create a new body and use the solid body feature to create the solid surface body out of it

Draft analysis of the final solid body :

After generating the final closed body perform the draft analysis with a draft angle of 2.98 ~3 degrees

And examine whether all the required surfaces are clearing the draft with respect to the main tooling axis of any draft applied surfaces can’t  be able to clear the draft analysis write a report mentioned what might be the reason for the surfaces not clear in the draft analysis and suggest the appropriate solution if else

 

Lot of the surfaces can able to clear the draft analysis but the surfaces which we mention in the class a surface draft analysis they have created then problem while clearing the draft in the final solid surface

here in the case of the class c surfaces some the surfcaes have a lower draft or the draft of negative type because if they create along with frespect to the correct sweep followed the quality of the surface obtained is not thet much good it might be twisty or not uniform so we continue with the negative draft

Lower substract:

In case of the door lower substract after examining the provided input surface we can able to detect a projection or an extension so we don’t need it for any further so, create a line and split the unnecessary surface

So my class A surface is ready

So my class A surface is ready with no poen boundaries in the given input surface

Tooling axis creation:

Extract the surface from the class A where the surface is entirely visible and easy for the manufacturing by viewing the surface in different orientations

Now create a point at the middle At 0 coordinates and create a line in point and direction method and the create line is our main tooling axis

Draft analysis of the class A surface: 

Perform the draft analysis on the class A surface  to check whether all the surface are clearing the draft of 3 degrees with respect the tooling axis we create then continue with the model or if you notice any flaws notice them with the class A team to rectify or else continue with the class B surface creation 

The class A surface is com[pletely clearing the draft analysis of the 3 degrees with respect to the tooling axis created 

Creation of class B surface:

In case of the lower substract offset the class A surface to a value of 2.5 mm beneath the class A surface then extrapolate the class B surface which would help to make the final trim with the class A and C combined surface

Creation of class C surface :

When the surface of the class C is parallel to the tooling axis then make use of the sweep with respect to the draft Direction to an angle of 3 degrees and the surface need to be outside the class A surface when seen from the normal direction with respect to the main tooling axis. And if the class C surface which need to create is perpendicular to the tooling axis then make the sweep with the reference surface With 90 degrees or with 87 degrees

Final surface formation:

Now join the class A surface with the class C surface and trim the class B surface with the join A and C surface

  

Solid surface body formation:

Now go to the part work bench and use the solid surface feature to create the solid surface body

Apply the suitable materuial to change the ambience of the solid body the material applied here is DS light Blue

Draft analysis of the solid body:

Preform the draft analysis on the solid body with a draft angle of 3 degrees and see the results

Almost all the surfaces are clearing the draft analysis in the B side direction.

Some of the  surfaces are generating the negative draft or the draft angle less then the 3 degrees

These type of deviation in the draft angle on the surface is mainly due to the quality of the class A surface provided , if we manage to provide the correct draft it will lead to the distortion of the class c surface which leads to the difficulty in manufacturing the component so, report the above draft analysis of the solid body to adopt or alter the proper changes in the class A surface team.

Map pocket design:

Map pocket is the sub element situated right at the hub of the lower substract of the door trim panel . The processs illustrated is same as the prevous components first, we need to check the boundary of the given input surface whether there might have any open patches or else protrude the input surface as the required class A surface

The provided input surface is 

find out for any open patches by checking the boundary feature.

Tooling axis creation:

In case of the map pocket the we extract the surface in the Y direction orientation and use the point - direction to generte the tooling axis of the map pocket

Draft analysis of the class A surface:

Once the tooling axis is create analyze the draft for the class A surface with a draft angle of 3 degrees

So, its perfectly clearing the draft of 3 degrees with the generated tooling axis

Class B surface creation:.

Now step forward to create the class B surface deploy the 2.5mm offset of the class A surface to generate the class B surface beneath the class A surface

.

Extrapolate the class B surface edges to form the perfect trim with the class A & C join

Class C surface creation:

Now create the class C surfcae which is an intermediate surface between the class A and the class B surface generally like a fill between the  two surfaces created with the help of the sweep feature with a draft of 3 degrees

along the tooling axis direction and with a draft of 90 degrees along the reference surfcae sweep

Final surface creation:

Once all the surfaces are created that is the class B and the class C surfacesthen join the class A & class C surfcaes and trim the  join surface with the class B surfaceto form the final closed surface

solid body creation:

Go to the part workbench and use the close surface feature to form the solid body out from the close surface body and perform the draft analysis

Draft analysis of the solid body:

Now perform the draft analysis with a draft angle of 3 degrees on the solid body

The results obtained are

Almost all the surfcaes are clearing the draft of 3 degrees along ther B side but some of the surfaces thet leads to a lower draft opr the negative draft mainly these issues rise when there is an issue with the class A surfcae .Here the class a draft is perfect but the curvature of the class A surface at the corner edges is not that much good, so during the class C surface generation the class c might not be that perfect to claer the draft angle of 3 degrees if possib;le to manage the surface to clear the draft the quality of the curvature formed at the corner or at the irregular curvature is impossible to manufacture So, make areport regarding issuesx due to the curvature defects and repoort the draft defects to the class A team so they will make the necessary adjustments in the class A surface if necessary

Here the draft is nearly approach to the negative 1 degrees this is due to the curvature of the class A at the junction

From tye results we obtain from the draft analysis of the solid body  we could come to conclude that the quality of the surface provided in the input surface is not good that is the surface doesnot have any draft in the class A itself so we need to get a report to alter the changes in the class A surface from the team 

Bottle holder design:

The input surface provide for the bottle holder is

Check for the open patches if exists , here in case of the bottle holder the oe particular surface is creating a problem in the further solid body creation . So ,here we use the join command and use the sub elements to remove feature to remove the particular surface from te input one and use the multisection feature to complete the class A required surface

So the updated class A surface is.

Tooling axis creation:

In the case of the bottle holder use the flat surface and extract the surface and create a point at the 0 coordinates and use the point - direction to create the tooling axis 

 Draft analysis of the class A surface:

Perform the draft analysis of the class A surface with a draft angle of 3 degrees the result  obtained is 

In the draft analysis some of the patches are red ( the draft is 0 or below zero ) and some in blur region shows that the draft is ( greater than 0 and less than 3) 

So we need to report to the class a team as te draft on the given input surface is not appropriate and need to get an update a class A surface So in this we need to continue forward with this draft analysis results for the further creation 

Class B surface creation:

Now offset the class B surface to 2.5mm following the master section beneath the class a surface and extrapolate the class b edges to an extent to form the proper ytrim with the class A and C join Choose the correct direction for offsetting the surface

 Class c surface creation:

Now create the class C surface with the aid of the class a surface and the sweep feature along the draft direction and the reference surface parameters . So provide adraft of 3 degrees along the draft direction making the direction of the draft as the main tooling axis and 90 degrees draft with rreespect to the reference surface

Final surface creation :

Once all the surfaces are created that is the class B and the class c surfaces join the class C surface with the classs A surface and trim the joined surface with  the class b surface 

This is the final closed surface with the class B & C surfaces 

Solid surface creation:

Once the closed surfae is created then go to the part workbench and use the solid surface feature to generate the solid body out of it 

Draft analysis of the solid surfcae body:

perform then draft analysis of the solid body with a draft angle of 3 degrees

The obtained results are the 

The entire surfaces of the solid body cannot be able to clear the draft analysis in then solid body because of the errors that spotted on the class A surface draft analysis so we need to make a report including the errors that spotted on the solid body too and submit to the respective team to alter then changes in the input surface to obtain a proper output

This negative draft is mainly due to the inclined curvature edges and the improper continution of the edges along the surfaces these are the changes that need to be updated and rectified by the class A surface input team 

Once all the solid bodies  of the components are generated we need to move onto the B sifde attachment features

The B side attachment features may include the 

1. Dog house
2. Ribs
3. Screw bosses
4. Flanges
5. Snap fits
6. Heat stakes

B side attachment features:

Once all the solid bodies are completed the assembly would be like 

  

The input surfaces of the door trim panel provided is 

so for the final solid surface components we need to provide thye proper attachment features by adopting  the industry design standards sand design parameters considerations

AS a design engineer we need to have an idea regarding how a component need to connect wityh the adjacent component either by the flanges and the heat stakes assembly or with the flange and the locator assembly or with the dog house and the push pin etc 

So we need to move step by step for creating the proper attachment features on each and every individual components of the door trim panel for the assembly of the component 

Lower substract attachment features:

Based on the master sections provided for the for the input surface of the lower substrate it indicates theat the heat stakes are positioed on the surface

Following the master section wee need to create the heat stakes on the lower substract B side 

Heat stakes :

Process for heat stakes assembly:

In thermal staking, also referred to as “heading or riveting”, the controlled flow of the molten plastic is used to capture or retain another component, usually of a different material.Thermal staking provides an alternative to welding when the two parts consist of dissimilar materials which cannot be welded or when simple mechanical retention of one part relative to another is adequate .

The most commonly used application involves the attachment of metal to plastic. A hole in the metal part receives a pre-molded plastic boss. The thermal tip contacts the boss and creates localized heat. As the boss melts, the light pressure from the horn forms a head to a shape determined by the horn tip configuration. When the heat is terminated, the plastic material solidifies and the dissimilar materials are fastened together.

So taking the references from the master section here we need to make a note of that whenever we take the reference from the master section the referenced elrement should be isolated from the master section 

so start working on the heat stakes creation and provide the support it with ribs on the four sides to add additional strength to the heat stake 

Design parameters:

1. Height we need to follow the master section
2. Draft provided on the outer and the inner face with an angle of 0.5 degrees

Pad the sketch with a height represent in the master section taking reference as the tooling axis direction

Now apply the draft of 0.5 degrees on both inner and outer edges.

Now create the ribs for the additional support .

Ribs provides a mean of strength and stiffness to the molded component without increasing the overall wall thickness

Ribs basically facilitates:

1. Locating and arresting the components of an assembly
2. Providing alignment in mating parts
3. Acts as a guides or stops in mechanisms

Design parameters:

• Draft: 0.5 Degree per side (minimum) and maximum upto 1.5 degrees
• Thickness of ribs: 40 to 50% of wall thickness
• Height: ≤ 5 times the wall thickness
• Spacing (for more than 1 rib): 3:1- steel height/width ratio (maximum). h/w =3 or2(preferred) where h is the height of the rib and w is the space between two ribs.
• Minimum thickness at the tip: 0.75mm
• Rib fillet Radius: 0.25mm max or 0.125*thickness of the component
• Rib root thickness should not be more than 30% of the wall thickness.

Now pad the sketch and apply the draft analysis with reference to the tooling axis

Height is 13.5 and after providing the draft we should need to have a width at the top should be greater then or equal to 0.75 mm 

The thicknesss of the component is 1.2mm thet is nearlt 50% of the wall thickness of the componenet 

thickness =50% of 2.5 = 1.25mm

The result of the draft analysis are

Heat stake:

Ribs :

Apply the fillets of 0.25 mm minimum on all the sharp edges and also you can apply chamfer for the tip of the ribs  and apply the boolean operation of unoin trim to combine tyhe ribs with the heat stake

So we need to position the heat stakes all over the component following the distance between the two hewat stakes is 50-100 mm

Another attachment feature we create is 4 way locator as when there is a need of more heat stakes but because of the design rule if the distance is not sufficient enough tio create the another heat stake then we create theb  locators and the height of the locator mush be higher than the heat stakes

Locators:

• Locators are used to locating the position of the mating part while assembling.
• The design rule for the locator is mostly the same as the rib but the height of the locator should be more than the heat stakes at a min of 5mm.
• The locator also constrains the movement of the mating part.
• The gap between Flange and the locator should range between 0.5mm and 1 mm.
• There are two types of locators.

         1. 2-Way Locator.

         2. 4-Way Locator.

The design rules follows the same as in case of ribs foloowed by some changes the sketch is

The height should be greater than the heat stake and providev a draft of 0.5  degrees selecting the neutral elament as the sketch plane and the pulling direction is the main tooling axis 

The final attachment of the 4 way locator by applying a minimum fillet of 0.25 mm on all the sharp corneres and at the top apply thenchamfer of length and angle of 3 mm and 45 degrees 

The width of the locator at the top must be greater than or equal to 0.75mm

The draft analysis of the component is 

3. Dog house creation:

DOGHOUSE- Doghouse is an engineering feature used in the plastic trim design which helps to remove sink marks formed on Class-A surface while creating attachment feature on Class-B surface. Doghouse is a supporting feature, other features like locators, heat stakes, pushpins are mounted on top of doghouse for fixing and assembly purpose. Doghouses are subjected to draft analysis to prevent breakage of the component during ejection from the mould.

Here I has used a 15*15 dog house padded to a height of 40mm 

Apply the shell of 2.5mm to make a cavity in the dog house 

Now provide an ouside draft of 1.5 degrees on the outer walls taking the pulling direction as the main tooling axis 

Now apply a draft of 0.5 degrees on the inner walls of the dog house taking the pulling direction as the side core tooling axis

 So generally the thickness of the component at the intersection of the dog house with the lower substract is 2.5 mm but with this thickness there may be possibility of plastic defects include the sink marks at the bottom So, the thickness at the contact is reduced to 1mm to 1.2mm as per the thickness of the plastic product. 

For this we generally provide coring for the dog house at the bottom that means the thickness of the componennt would be 1 mm from ouside walls of then dog house 

The thickness maintained should be 1 mm from the ouside walls of the dog house 

 The height of the coring provided is 3mm  upto 6 mm

 Use the booolean operation to remove the component from the dog house and apply the draft of 0.5degrees on the walls of the coring 

Rib cage:

For  provoding the additional support for the dog house we create a rib cage with two ribs of 1 mm thickness and providing a draft of 0.5 deg with respect to the side core tpooling axisb 

 At the top surfcae provide a cutout to provide the room for the pushclip to positrion it in the top of the dog house 

PUSH PINS- Push pins are used for joining one component to another . These are basically attached to the doghouse. For creating the push pins the following reference was taken for dimensions.

The cutout sketch is 

Pad the sketch and make the boolean operation to remove the cutout from the dog house and apply a draft of 0.5 degrees on the edges of the cut out 

Dog houase generally claer the draft analysis in two tooling axis directions one along the main tooling axis and other along the slider axis or the sude tooling axis 

 The draft analysis results are 

Along the slider with a draft angle of 0.5 deg

Alongb the main tooling axis with a draft of 1.5 deg

 SO on the lower substract we need to provide upto 3 dog house maintaining that there might not be any engineeering feature with in a direction of the slider movement upto 90mm (minimum distance )

We use the translate option from point to point translation to copy and paste the dog houses atb arious locations and use the rotate option to change the direction of the opening for the slider 

 These are the 3 dog housess along with their slider axis 

The draft analysis of other two doghouse with respaect to theire side core tooling axis is 

Dog house 02

Dog house 03:

 

The draft analysis on the outer edges of 1.5 deg draft is 

And the heat stakes & the locators  on the lower substrat along with the draft analysis of 0.5 deg along the main tooling axis is 

The draft analyiss is 

 Now with the help of these heat stakes and the locators create the flages on the adjacent componemts to form a proper assembly among the components 

B side attachments  on the Door arm rest:

Flanges are the joining features that help to assemble different components. The mastersection was used to make flanges. After creating one flange point to point translation is used to translate the flanges. We need to provide a draft of 0.5 degrees for the flanges . The gap between flanges should be 50-100 mm. Boolean operations were used to add attachment features into closed body

Design:

In case of te door arm rest we need to folow the master section provided for the flange creation

The thickness of the flange is equal to the thickness of the plastic component that is 2.5 mm

The draft provided is 0.5 deg

Apply requierd fillets on all the sharp edges

The sketches taking the references from the master section are

   

 The surfcae of the flange formed is 

 Thiocken the surface in the part workbench with a thickness of 2.5mm

The uneven surfaces on the thicken surface can be split with the surface offset 

  

Apply a draft of 0.5 deg on the edges of the flange

Now apply then proper fillets on the corner edges 

Now make a hole on the hole to position then heat stake or the locator with respect to the flange for proper assembly 

The diameter of the hole should provide of claerance of 0.5 to 1 mm between the flange and the heat stake or with the flange and the locator 

 Pad the sketch and apply the draft of 0.5 deg with respect to then side tooling axis

 

Use the boolean operation to form the perfect hole on the flage and the claerance thus obtained is 

So we need to cfreate the flanges on every position with respect to the heat stakes or the locator which are situated on the lower substract for the assembly

Now perform the draft analysis with a draft angle of 0.5 deg

Now use the boolean operation to attach the flanges to the door arm rest

B side attachments on the map pocket :

In case of the map pocket we use tye master section references for creating the flanges for generating the proper assembly between the compoemts

Here we consider two master sections one with respect to the lower substract and other with the bottle holder

Take the references from the master section and isolate them so that whenever there may be changes in the master section the sketches cannot create any problem

 The flange surface formed is 

Thicken the surface to 2.5mm and apply a draft of 0.5 deg and apply the proper fillets

apply the proper fillets as we mention previously on the arm rest component

Now create a hole for the heat stake attachment in the flange

Apply the draft of 0.5 deg on the padded hole too

Now use the boolean operation to remove the padded hole part from the flange 

Now create and position the flanges with respect to the attachment featues on the lower substract and the bottle holder

With respect to the bottle holder

Now create the attachment features pof heatr stakes and the locators for making the assembly of the componenr with the bottle holder

Following the same fdesign principless as mentioned above 

The draft analysis of the B side featues on the map pocket are

 B side features on the Bottle holder:

 In case of the bottle holder there didnot provide any master section for the B side attachment so we need to follow the design parametes and create the flanges with respect to the attachmnets on the lower substract and the map pocket

 For creating the flanges to follow the class c surfcae we provide an inetersect and cpincide the sketch with it 

Now start creating then sketches with proper design rules 

Now the flange surface created is.

Now thicken the surface to a value of 2.5 mm and provide theb  draft of 0.5 deg along with the fillets 

Now create a hole for the attachment to assemble on the flange 

The total flangesc created with respect to the lower substrtract and the bottle holder is

The draft analyis results of the B side attachments are

Assembling the push pins to the dog houses

For this create an axis on the push clops and create the axis on the top cut out on the dog house and apply the coincidence constraint 

And apply the coincidence constraint fore the plane for proper sitting of the pushclip on the top of the dog house

 THe final components with the Bside features is 

conclusion:

The Design of The Automotive Door Trim Panel from a Class A surface to a Closed Part Body with all the necessary attachment features by following all the design rules using CATIA V5 is done Successfully and all the required CATPart and CATProduct files are attached. 

The tree structure is 

The enlarged tree structure is 

Door arm rest:

LOwer subsract:

Map pocket tree structure

Bottle holder tree structure