Roof Design

ROOF CHALLENGE

OBJECTIVE:

• Study the curvature of the roof class A surface.
• Create the flanges of roof wrt the master section.
• Create the front and rear roof rails following the master section.
• Create the bow roofs by understanding the curvature of the roof.
• Create the center roof rail along with the reinforcement.
• Perform the heat distortion and snow load study to rectify the positioning of the all roof rails.
• Performing the Draft analysis.

ROOF

An automobile roof or car top is the portion of an automobile that sits above the passenger compartment, protecting the vehicle occupants from sun, wind, rain, and other external elements. Because the earliest automobiles were designed in an era of horse down carriages early automobile roofs used similar materials and designs.

The roof also ensures the safety of the passengers from the obstacle or during the collision by imposoing proper roof rails.

TYPES OF CAR ROOF

1)CONVERTIBLE

A convertible is a passenger car that can be driven with or without a roof in place. The methods of retracting and storing the roof vary between models. A convertible allows an open-air driving experience, with the ability to provide a roof when required. Potential drawbacks of convertibles are reducedstructural rigidity. (requiring significant engineering and modification to counteract the effects of removing a car's roof.

The majority of convertible roofs are of a folding construction framework with the actual top made from cloth or other fabric. Other types of convertible roofs include retractable hardtops (often constructed from metal or plastic) and detachable hardtops(where a metal or plastic roof is manually removed and often stored in the trunk).

2)SUNROOF

A sunroof is a movable panel that opens to uncover a window in an automobile roof , allowing light and fresh air to enter the passenger compartment. Sunroofs can be manually operated or motor driven, and are available in many shapes, sizes and styles. While the term sunroof is now used generically to describe any glass panel in the roof, the term "moonroof" was historically used to describe stationary glass panes rigidly mounted in the roof panel over the passenger compartment. A moonroof has a glass panel that is transparent and usually tinted. Previous terms include Sunshine Roof, Sliding Head and Sliding Roof.

3)HARDTOP

A hardtop is a rigid form of automobile roof, which for modern cars is typically constructed from metal. A hardtop roof can be either fixed (i.e. not removable), detachable for separate storing or retractable within the vehicle itself.

The pillars hardtop (often referred to as simply "hardtop") is a body style of cars without a B-pillar, which are often styled to give the appearance of a convertible design design.

4)T TOP

A T-top (UK: T-bar) is an automobile roof with a removable panel on each side of a rigid bar running from the center of one structural bar between PILLARS to the center of the next structural bar. The panels of a traditional T-top are usually made of auto grade safety glass.

The removable panel roof was patented by Gordon Buehrig on June 5, 1951. It was first used in a 1948 prototype by The American Sportscar Company or “Tasco.”

The 1968 CHEVROLET coupe was the first U.S.-built production automobile to feature a T-top roof.This increased the popularity of the coupe, such that it outsold the convertible and later led to the discontinuation of the Corvette convertible after 1975 until it was revived in 1986. Post-C3 models were built with a TARGA TOP instead of a T-top.

ROOF DITCH AREA AND FLANGES:

The roof ditch area and flanges are created in relation with visibility criteria, safe head distance , head liner and various other factors which govern the size of the roof rails and also which are related or connected to the roof like windshield.

MASTER SECTION FOR THE ROOF RAILS AND DITCH AREA AND DESIGN IN NX CAD:

ROOF RAILS

1)FRONT ROOF RAIL

The front roof rail plays a vital role in designing the roof rails because front roof rail forms the link between the roof , wind shield glass and head liner (trim).The visibility criteria and the head room space are the important factors which should be governed while preparing the master section for the front roof rail.

2)REAR ROOF RAIL

The rear roof rail is connected to the backdoor part so it plays vital role in design of the roof as it is in co-related with the other part as well .

3)BOW ROOF RAIL 1&2

The bow roofs are there to give the strength to the roof of an automobile , the number of bow roofs are governed by the curvature of the roof .If the curvature is nice as provided by the class A surface then only single bow roof and center roof rail are sufficient to provide the strenth to the roof of the automobile.

BOW ROOF 2

CENTER ROOF RAIL WITH REINFORCEMENT.