Challenge 6 : Concept Modeling of Side Fender

Tittle: Side fender modelling

Objective :

To build a concept modelling of side fender using curves and surfaces

Introduction:

Fender is the American English term for the part of an automobile, motorcycle or other vehicle body that frames a wheel well (the fender underside). Its primary purpose is to prevent sand, mud, rocks, liquids, and other road spray from being thrown into the air by the rotating tire. Fenders are typically rigid and can be damaged by contact with the road surface.

Early automobile fenders set over the wheels to prevent mud, sand and dust being thrown on to the body and the occupants. Fenders typically became a more integral part of overall auto bodies by the mid-1930s.

One of the primary functions of a fender is to keep dirt, dust, and road debris away from the wheel and front braking system. Many have small flaps or wings that are designed to enhance this protective function.

Autodesk Alias is used in automotive design for generating Class A surfaces using Bezier surface and NURBS modelling method.

Design methodology:

Description:

1) Import the image

The image of the fender will help us to build the concept model of the fender. Steps for importing Image File -> Import -> Canvas Image -> Go Scaling the Image: After placing the image in appropriate layer the blueprints of the fender will be scaled down to appropriate size so that it can be positioned accurately with respect to the other views. This will help in generation of curves at appropriate places and with desired shape of the blueprint. Steps to scale the image: -> Press ad* shift along with clicking and holding the left mouse button. -> Select Pick object - Select the image -> Press ctrl shift along with clicking the middle mouse button -> Select Scale -> Hold left mouse button and move up and down to scale the image larger and smaller.

Steps to move the image: Palette -> Transform -> Move. The image is given some amount of transparency so that the curves can be traced easily on it at required positions Steps to set transparency. -> Press shift ctrl along with clicking and holding right mouse button. -> Select plane editor. -> Set the value of the transparency level for the different views of the image in it

2) Layers

Creation of different layers as per requirement. Layers allow us to organize related objects into groups that you can pick, display, and edit individually or together.

3) Curves

Generating the curves to trace the required shape of the fender. After placing the image at required positions the curves are traced on it to give desired shape of the fender: Cv Curve - It lets to create new NURBS on the scene by placing CVs. In order to join curves at few places blends feature is used to give desired shape. Steps for showing blends bar-Palette -> Blend -> Blend Curve Toolbox -> New Curve Trim At few places the curves are trimmed to remove curves at certain places where it is not required. Steps to perform curve trim: Palette -> curve edit -> crvsct -> Select the curve -> click on "GO" present in bottom right corner -> select the curve where you want the portion of the original curve to be removed. The final view of the curve network which was build by using the features in curves is shown below:

4) Surface

Generating the surfaces on the curve to design the concept model of the fender. After the file in which the model of the fender is being imported, the surfaces needs to be made with the help of these curves. For this purpose surface features are used which are present inside the palette bar. The steps to use the surface generation features are: Windows -> Palette Surface By following the above procedure the surface generation features can be used. Few of the surface generation features that were used in this project is listed below:

1. a) Square
2. b) rail
3. c) skin
4. d) ff blend

After completing the generation of surfaces with the help of features in surface, surface edit, object edit etc, the complete concept design of the fender is generated.

4) Fillet

The fillet is added to smooth between surfaces so that no sharp edges are formed.

Steps to add fillet :

srfillet-> pick two surfaces-> adjust the radius-> hit go

5) Final check

Final checks are done to achieve a smooth and nice shape of the side fender.

Screenshots of views:

Front view

Top view

Side view

Isometric

Conclusion

The side fender was successfully built using the curves and by using the right surface commands and by adding fillets for a smooth surface.