Roof challenge

Roof Design:

This report is about the roof design done with respect to the inputs like styling surface, master sections of various parts, design parameters, and andards used.

Objectives:

Create a Car Roof model based on the styling surface, master sections given for various parts with mastic points and reinforcements. Determine whether the design is complying with Heat distortion criteria through curvature study on the roof.

Judge the snowed condition criteria of the roof model using the prediction formula to conclude if the roof can withstand the load acting upon it.

Prepare a section modulus study for roof parts Bow roof 1, Bow roof center and Bow roof 2 in the OY section.

Draft analysis of all the parts to check for tooling feasibility.

Introduction:

The roof is an important part of an automobile as it protects the occupants from various environmental conditions like Heat, Snow, Rain, and winds. There are many types of the roof

which differs based on the variants of the car and the region. The roof must be designed in such a way that it would able to withstand any load or impact due to accidents or objects falling

the above-said conditions. Also, other factors

on it and other environmental factors. So, the design done is based on the standards and design intent which makes the roof to withstand

Headroom, aesthetics play a role in the design.

The roof is an assembly of many parts like Front roof rail, Bow roof, Bow roof center, and reinforcement center. The number of bow roofs is based on the length of the roof and

sometimes even the bow roof center is avoided in cases like small cars. The roof is attached to the body of the car using mastic sealants provided between bow roofs and the front and

rear rails.

Roof Assembly:

Bow Roofs and rails:

Rear and Front Roof rails:

Heat Distortion criteria:

Predicting Heat Distortion for the roof is important since it is exposed to heat for a long time and high temperatures will affect the roof structure if the design does not

conform with the heat distortion criteria. This study helps to determine the positions of Bow roofs to provide strength to the roof to avoid bending or deformation of the

roof due to heat. Bow roof curvature study using the below formula will help us to check whether the Bow roof positions impart required strength to the roof.

Prediction Formula: W-1.73 X 10^-3XL+1.85X10^-8X(R^2/t)-1.10 X10^-3X1-2.68

L-Roof Length in the X direction (Roof dimension with OY)

R- Roof curvature -2(Rx X Ry)/(Rx-Ry) (Rx-X curvature, Ry -Y curvature)

t=Roof Thickness (mm)

I= Bow roof span (mm)

Snowed criteria:

The roof of an automobile must be able to withstand load especially snow which results in heavy load acting on the roof. It the root is not able to withstand it, there will

be deformation of the roof. To prevent that, Snowed criteria calculation helps us to determine whether the roof design will withstand the snow load.

CONCLUSION 

Roof assembly created susscess fully created in NX CAD softwer.