Roof Design

OBJECTIVE:

1.Main objective of the project is to create the Roof Sheetmetal design in NX cad, and also designing Front roof rail, rear roof rail, bow roof front, bow roof rear, center roof rail and Reinforcement are creating to build the strong roof.

2.Do curvature study on Roof and performance calculations for Heat distortion and Snow load criteria to determine the position of the Bow roofs.

3.Finding the moment of inertia and section modulus for Bow-roofs and center roof rail.

4.And, also finding the Draft Analysis of each part.

SOFTWARE USED: NX 12.0

• To design the Sheetmetal ROOF in NX by using some Solid/Surface features.
• NX Software is a flexible and powerful integrated solution that helps you deliver the products faster and efficiently.
• NX Cad software is widely used automotive, aerospace, thermal power station. Because of it is having modelling, drafting and manufacturing platform.

DESIGN CONSIDERATION-

1. Visibility criteria

2. Head clearance

3. Curvature study

4. Hear distortion and snow load criteria

5. Draft analysis.

ROOF CRUSH TEST:

OVERVIEW OF THE TEST:

Roof strength evaluations consist of a quasi-static test conducted on a vehicle’s roof in a manner similar to tests used to judge compliance with Federal Motor Vehicle Safety Standard 216 (Office of the Federal Register, 2009). The main differences between the procedure specified by the Insurance Institute for Highway Safety (IIHS) and that specified by the U.S. federal government are that the IIHS procedure are,

• Specifies testing one side of a vehicle’s roof
• Does not include a headroom criterion
• Specifies testing to a given displacement instead of a given force level
• Specifies setting the vehicle’s pitch angle during testing based on the measured on-road pitch angle.

An overall rating is assigned based on the peak strength-to-weight ratio (SWR) measured within 127 mm of plate displacement.

TESTING OF ROOF:

Roof strength evaluations are conducted on a quasi-static test system manufactured by MGA Research Corporation (Figure 3).

The system consists of an upright assembly and an attached loading head that can be fixed at varying heights from the ground as well as at pitch angles ranging from −5 to +5 degrees to accommodate testing on the driver or passenger side.

The roll angle is permanently fixed at 25 degrees. Four hydraulic actuators control the movement of the platen along two linear guides. The entire system is mounted on a T-slot bed plate anchored to the floor of the test facility.