Hood design-Week 2

A hood design comprises of several technical and engineering features involved in it. It has a seperate Hood design engineer in the company. The main perspective of a Hood design is that the Hood should not hide the road view of the driver. Also it has a adult headstock area (which is the driver end portion of the Hood) and Child Headstock area (which is the front end portion of the Hood).

The Hood contains of four portions: Hood outer panel, Hood inner panel, Striker, Hinge Assemblies.

The Hood outer panel:

It is the exterior of the Hood. It should not have any dents or joints that affects the aesthetic view of the Hood. Consumers dont like the hood which doesnt looks good. So the Assemblies or joints associated with the outer panel should be done on its inner side and it should not affect the outer aesthetic view.

The Hood Inner Panel:

The Inner panel is responsible for the force distribution to the outside the vehicle when ever the Hood front end hits or accidents.

The inner panel has a Master section given by the company or tby the design enginners. It is nothing but the inner cross secton of the inner panel of the hood. The Sheet has a maximum of 10-15mm to be forged or embossed without affecting the sheets. So if the sheet has to be forged to more than its limit then it has to be done in a step manner.

Different tools or softwares can be used to design the Hood sheet. Primarily the Hood surface of outer panel is feed into the software. Here the NX is used.By using several commands the inner panel is designed. Few of those commands are:

• Offset curve on face.
• Offset surface
• Trim Sheet
• Extend Sheet
• Sew
• Thicken
• Law Extension
• Emboss

Then the Position for Striker and the Hinge assemblt are placed . These position should be flatten and thus those parts can be assembled and fitted on it easily.

Into the inner panel of the hood the Mastic points are provided. These are the points which have an influence of 80mm around it. The glue or paste or placed which joins the outer panel to the inner panel and withholds them together

The cuts that doesnt have any particular desgn parameters are provided in the inner hood to spread the force outwards.

Striker:

The Striker is the part which locks the hood with the vehicle body. The placement of striker also has an engineering feature. The Striker should placed tangential to the circle formed whose centre is the mid point to the line that joins the hinges.

Hinges:

Thesre are two hinges which connects the Hood to the body of the vehicle. The degrees of freedom of the hinges decides the total angle of the hood while opening it. There are few changes in the maximum angle of opening of the hood which completely depends upon the region the vehicle is consumed. It completely depends upon the average height of the adult which should not hit their head while opening the hood and repairing or checking the inner parts in the bonnet compartment.