Hood design-Week 2

Challenge 2 Hood inner Panel Design.

Input data received

1.Outer panel

2.Hinge assembly

3.Striker assembly.

4.Master section.

The challlenge is to design a Hood inner panel with reference to outer panel surface.

Use offset surface of the outer panel surface and starting working on it.

Designing procedure and consideration.

First opened NX assembly file and loaded the outer panel skin.(fixed constrain)

Trimmed the Surface into half and started working on half surface.

Made copy of the surface and named it inner hood.

Loaded this file and fixed the constrain

offset copied the outer surface to 1.7mm as mentioned in the master section

Now this is the working surface for inner panel.

Extracted the outer curves and offset the curve on the surface offset to 1.7mm, to 20mm and trimmed the inside area

Extracted the outer curves and offset the curve on the surface on the surface offset to 4mm, to 22 and 35mm and trimmed the inside and outside area

Extracted the outer curves and offset the curve on the surfacret to 25mm, to 50mm and trimmed outside area

Then joined the 35mm (4mm offset) trimed surface and 50mm (25mm offset) surfaces with thru curves but the surface generated was not uniform or smooth so used bridge curve and swift command to create a surface

used face blend to create radius of 15mm and radius of 100

Created surface between 20mm trimmed (1.7mm offset) surface and 22mm (4mm offset) surface using through curve.

Joined the surfaces using SEW command and Edge fillet both the corners radius 6mm

This was the output.

Then the profile was drawn using sketch command on the plane parallel to the surface and projected on the surface for embosing and trimming

the out put is as below

Mastic points planned in a distance of less than 160mm circular area

Corner edge fillet for all sharp corners and draft angle of 10deg considered on embosing surface.

Also crash force disipating away from passenger of the cars towards sides was also considered as shown.

Next importing of hinge assembly and striker assembly in to assembly environment

Embosing was planed as per the hinge assembly by creating angular datum plane and offset to the origin as shown below.

The angle close was 7deg and 590mm offset from origin.

Then sketch was drawn on the plane and projected on the hood inner surface. This projected profile was embossed. The embosed surface parallel to the datum plane.

Then the hinge assembly was placed on this embosed surface with touch constraint and parallel to axis constraint.

Then the whole assembly was mirrored and sewed together.

while mirroring the inner hood surface there were some gaps and overlappping. The edge was extended by 2mm throughout and then trimmed to the mirror plane and completed.

Now the hinge assembly also mirrored and a point in centre of the circular hinge was created on both end hinges. A line was created between these two points and circle of 630mm app was created for fixing the stricker perpendicular to the circle.

Now the striker assembly was opened and a plane created exactly in the centre of the part and a verticle line was drawn passing through centre of curved stricker for reference to place the stricker in axis with reference to hindge axis.

The final assembly as below after all constrain

Next was the outer hood hemming

offset the outer surface to 2.65mm (0.75+0.2+0.75+0.2+0.75+0.2)

Created curves on the outer edges and offset by 0.5mm with radius of 30mm on sharp corners and created vertical surface using law of extension with draft 10 degre. With all trimming the hemming operation was completed.

A hemming curve was created with face blend 3 faces option. After hemming the corner were trimmed as mentioned.

Finally thickness was added for outer and inner hood panel. The outcome is as below which is sectioned view of outer and inner hood panel.

Note:

This is my second attempt.

In the first attempt the whole assembly was finished and thickness was added but after adding thickness and sectioning the view was mis match.

possible reason is Hood inner panel not fixed constrained intially. I fixed at the time of assembly.