Week 11 - Final project

Aim: To Design Automotive Door Panel Trim by using Catia V5, With a given Class A surface and crating a B side Feature as per Design Guidlines Rules.

Objective:

• To create Tooling axis and perform a draft analysis for given Class A surface of each part.
• From the Class A surface create Class B & C surface and finally closed surface for each part.
• Perform draft analyis for closed surface.
• Creating a B side feature for Door panel like [Dog house, Flanges, Heat stake, 4 way locators, Screw Bosses]
• Finally assembly the Push pins on the dog house.

Components Involved in the Door Panel are

1. Lower Substract
2. Door Arm rest
3. Lower Map pocket
4. Map pocket

Automotive Door Panel

The door panel is the interface between the interior of the car and inner working 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. Genearlly door panel is divided in to the parts like Door arm rest, lower substract, map pocket, lower map pocket for easy design. 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. 

 An additional consideration is their ability to protect occupants from injury during a side collision, where most injuries are inflicted on the chest and pelvis as a result of crushing force of the door

Door panel Materials

Door panels were formerly made of cardboard with an upholstered interior finish of vinyl, leather, cloth, carpet, or other materials for the decorative trim. Modern cars typically have door cards made of plastic, most often using injection moulding, as well as incorporating other decorative materials.

Components for Door Panel

Class A surface

Class A surface for the Automotive door panel is recevied from the Stylish team, In the automotive industry for Class A surface seperate team is allocated to  design class A surface, this is first input for design for plastic parts.

Before proceduing to further design first check the class A surface if there is any gap is there then modifiy the class A surface.

First step to design door panel

TOOLING AXIS

Creating a Tooling axis

The tooling direction is used to find the direction in which the parts is removed from the core & cavity. By using a Tooling axis draft analysis is formed for each components.

 a.Map pocket

Creating a tooling direction on the Map pocket , create a point on the class a surface respectively as 0 value, then create a line with respect the Y direction. Also checking a Draft analysis for the given class A surface.

 b. Lower Map pocket

Creating a tooling direction on the Map pocket , create a point on the class a surface respectively as 0 value, then create a line with respect the Y direction. Also checking a Draft analysis for the given class A surface.

But performing a draft analysis for class Asurface of  Lower Map pocket some area shows a Blue surface as 0 deg, here we don't habe a right to modified a Class A surface so we need to inform to class A team to provide a Draft angle.

 C. Lower Substract

Creating a tooling direction on the Map pocket , create a point on the class a surface respectively as 0 value, then create a line with respect the Y direction.Also checking a Draft analysis for the given class A

d. Door Arm rest

Create a tooling axis for Arm rest by create a point on the surface respectively with axis system. Now create intersction on the Z-X and Z-Y axisrespectively based on the point.

Creating the bisecting line to the both intersection and create bisect for that lines. Hence we get final tooling axis on the Door arm rest, and Side core axis. also perform Draft analysis.

Class B Surface

Creating a Class B Surface by extracting a class A surface at certain offset distance by using a master section as a reference for each part seperately.

 a. Map Pocket

 b. Lower Map Pocket

 C. Lower Substract

d. Door Arm Rest

Finally by doing a offset of 2.5mm by using master section distance we got a Class B surface.

Class C Surface

By extracting the boundary of Class A surface and at the edges then make in to them by using a smooth curve to sweep the curve by using support srface to the 90 degree.

 a.Map pocket

After triming with class C with Class B surface than join with class A surface, finally we get closed surface to known that use boundary option it shows as selected body is closed.

 b. Lower Map pocket

 c. Lower Substract

 d. Door arm rest

After extracting a boundary of Class A surface then extroplate a surface of Class B surface up to certain distance to trim with class A suraface to C surface. Finally Closed surface is formed.

To make a final components class C surface is trimmed with class B surface, then out put will get components with 2mm thickness, After trimeing the components check with boundary wether it has any open surface by using Boundary option we get the solution wether it has any open or closed surface it show the result as body is completely closed or not, do the same procedure for each components .

Draft Analysis for Closed surface

Map Pocket

As per the color scale, the minimum draft angle for all faces should be 2.9deg or above that, inside the color scale, green shows a draft angle of 2.9 or above 2.9degree, Blue shows between 0  and 2.9 degree .Red shows a negative draft angle as per the above figure , all faces are green .Hence this components has draft analysis successfully.

Lower Map Pocket

As per the color scale, the minimum draft angle for all faces should be 2.9deg or above that, inside the color scale, green shows a draft angle of 2.9 or above 2.9deg. Blue shows between 0 and 2.9deg, and red shows a negative draft angle , as per the above figure, some faces are green , blue, and red as well. hence our surface has not cleared the draft analysis at the red faces and blue faces using the main  tooling axis. The minimum draft angle at the blue faceis 0deg , so Class A surface needs to give a proper draft , required changes are forwarded to the styling team for modifications.

Lower substract

Door arm rest

In the door arm rest main tooling axis clear the upper surface as shown as green color but here under cut tooling axis is required sor side core tooling axis is created.

Engineering Feature/ B-side Feature

In the door panel all the parts are attached together by using B-side feature like Heat stake, screw bosses, 4 way locators, flanges.Flanges are attached to the map pocket, lower map pocket, Arm rest. Reamaining features are placed on the lower substract which will acts as acentral part for all the components it is mainly used to joint the remaining part.

Flanges

 All the flanges have been created by following the given master section. The thickness of all the flanges is 2.5mm, Draft angke is 0.5deg applied to all the flages. Edges fillet of 5mm applied to sharp corners. Slots for locators and heat stakes have been created onto the all the flanges.

Flanges for Door arm rest

 Map pocket

Lower Map pocket

Locators

Locators act as guiders, all the locators have been presented onto the lower substracte.Necessary holes are made onto the remaining parts to allow locators to move inside the parts. they are justs used to align the parts together and acts as temporary joints. four way locators have been created onto different locations on the lower substracts. The chamfer of 3*45 is used.

Here we used to only one 4 way locators because on the lower substracts heat stake also placed to joint other components.

 Heat Stake

The use of heat stakes is to attach two plastic components permanently, a total of 11 heat stake were placed at different locations on the lower substracts. one heat has been created onto armrest part which will be attached to the upper substracte. Following the master sections , the outer diameter of the heat stake is 7mm and the inner dia is 5mm,necessary slots are made on to other parts where heat stake will attach together , Draft of 0.5deg has been given to all the heat stake, all the heat stakes have ribs attached to them , all the ribs have 1mm thickness and 0.5deg of the drafts . the length of the ribs 12*12mm.

Heat staking also known as thermoplastic staking is the process of joining two dissimilar materials together. In the heat staking we use local heating and cooling to raise the temperature of plastic components and allows plastic reformng to be carried out. This reforming can be used in a wide varity of applications.

As per the color scale, the minimum draft for all face should be 0.49deg or above that, inside color scale , green shows a draft angle of 0.49deg or above 0.49deg .Blue shows between 0 and 0.49 deg and red shows a negative draft angle .As pwer the above fig all faces of heat stakes are green ,hence all heats stakes have clared the draft analysis successfully with respect to the main tooling axis.

While creating a Heat stake first create one heat stake by providing Ribs , draft angle everything than create a point up to 50mm distance between two heat stake use point to point command then copy the orginal heat stake than use past special option as a result with link command than transalute point to point.

Screw Bosses

The boss is one of the basic design elements of plastic moulding, Bosses are usually cylindrical because that is the easiest form to the machine in the mould and it is also the strongest shape to have in the moulded part. The boss is used whenever we need a mounting point,a location point, a reinforcement around holes. The boss may receive an insert, a screw or a plain shaft either as a slider or a press fit.

In other words, the boss is not as simple as it looks. depending on its use, it may have to stand up to a whole combination of forces-tension, compression, torsion, flexing, shear and bursting so it must be designed accordingly.

We can start with a general design rule, using the principle we have already developed for ribs and walls. The boss can be thought of as a special case of a rib. one that is wrapped round in the form of a tube. An ideal boss, designed according to rib rules, would not produce a sink mark or stick in the mould but unfortunately, the tubular form of the boss would not be strong enough in most cases. In a real-life, most bosses break some rib design rib by necessity. This means that boss design is a compromise between sink mark and functionality. Rigidity is the simplest aspect of boss design. This can be achieved by supporting the boss design. This can be achieved by supporting the boss with buttress rib, and often by linking the boss to a side wall. The support ribs can be designed to normal rib rules so that sink marks and stress points are avoided.

Dog House

Dog house is an engineering feature used in plastic trim design.Dog house are used as supporting feature, sometime other engineering features like snaps, locators etc... are mounted on them to increase their strength. Dog house are subjected to draft analysis to prevent breakage of the components during ejection from the mould cavity. Dog house and other engineering components are built on the Bsurface.

By using same method create a point on the surface use transulate option to form one more dog house on the surface.

Tooling axis has been created on the dog house main tooling axis and side core tooling axis are created 

Whiel useing a main tooilng axis outer surface will be drafted by inverting inside surface is drafted but by using side core inside surface will be drafted.

As per the color scale, the minimum draft for all face should be 0.49deg or above that, inside color scale , green shows a draft angle of 0.49deg or above 0.49deg .Blue shows between 0 and 0.49 deg and red shows a negative draft angle .As pwer the above fig all faces of heat stakes are green ,hence all heats stakes have clared the draft analysis successfully with respect to the main tooling axis.

Assembly Part

Bottom up assembly

The components are created in seperated part files and are then inserted into the assembly file.They are assembled at  their working position by applying assembly constraint to them. To create as assembly using this approach, it is recommended to insert the first components and fixs its position after properly orienting it in the 3D space. the components can be insertrd and positioned with reference to the first components.

Push Pins

The use of plastic push pins is to attach the plastic part to sheet meatal part.

Here three push pins are used to to place on the dog house, by using assembly constraints commondes as follows

Conclusion

The door panel has been sucessfully designed by following OEM Standards used in automotive industry. All the attachment features are properly placed at different locations. The designed parts meets all the desined objectives.