Hood design-Week 2

HOOD

Hood/Bonnet is an Opening body panel that covers the engine in a front engine vehicle. The Hood is also consider as another type of door in a vehicle as it consists of an outer panel and inner panel provides strength while the outer panel functions as the metal cover. Hood is used to decorate front portion of the car and add luxurious look.

Design Considration:

Hood of engine design in such a way that reduses air effect and all the maintenance part easy to do it should also protect from the exxternal distrubance on the engine. When car comes to an accident it must be impact force and distributed outside. So, it should be the Y-shape.

While designing Hood should take care of Safety, Quality, Stylling, and Manufacturing. The most important safety requirement to be consider while designing the hood is the Pedestrian Safety from the front side. Pedestrian Safety, it's a norm which provides safety feature to body when car get collide from the front side and reduce the injuries of the body.

Design Outer:

The following shows the hood panel with the hem. The body have the overall thickness of 0.75mm.

The outer panel is the upper cover design as aesthetics look of the car. It's physical significants as weight and dimesnsions is over the designer's liberations. The Hem involves the outer panel which cover the inner panel of the overall assembly.

Manufacturing Requirements:

Before get into the production it is very important to design it and look into the requirement. Material should be impact absorber and lighter in weight. Avoide to provide sharp corners and negative draft.

Outer Panel Thickness = 0.75mm

Inner Panel Thickness = 0.75mm

Reinforcement Panel Thickness = 1.5mm

Master Section:

It gives information of the Hood inner and outer panel to get the desired shape and size. After getting the shape embossing is feature which used to reised the surface. It also provides strength and direct the force from front collision towards the hinge and body of the car.

Inner Panel:

Inner Panel designer so as to apper better visualization, better view for the customer and one is to meet customer requirement of them by considering engineering fundamental behind hood design. It should have some feature like emboss at the hinge point which provides the better strength to the inner pannel of the hood.

Outer Panel with the Hem:

Hem is provided to the upper panel of the hood at the corner to provide the better grip between inner and outer panel of the hood. The Clearence between Hem and Inner panel should be near about 0.2mm.

Hinge:

It is used to mount the hood into the desired position so that it can be easily closed and open when required.

Latch:

It is mountedd in inner panel and provides locking system.

Mastic Data:

As the outer panel provides luxurious look so we can't provides nut and bolts or welding on that. So here Mastic sealant is used to pack the inner and outer panel included hemming. It is in the liquid form but when it goes into the hot bath furnace it get hard and provide strength to the hood.

Hemming:

Here, edge is rolled like U-Shape for joining and it also improve appearence of combined body.

Emboss:

Emboss covers and utilizes the material of the body to a particular portion hence the remained sheet metal material need to be removed to reduce the weight. Emboss concentrate the material within a particular area which improves strength and overall hood of the inner panel to outer panel. It also absorbs the collosion impact and try to avoid any harm to the passenger.

I Used Simens NX Cad. Main tools which I used in this model

Modelling:- Trim sheet, Offset surface, Curve on surface, Offset curve in face, Law extension, Trim and Extend, Face blend, Edge blend, Sew, Thicken, Extract geomentry.

Assembly:- Add components, Move components, Assembly constraints, Show and Hide.